platform/kernel/linux-rpi.git
2 years agocachefiles: Implement a function to get/create a directory in the cache
David Howells [Thu, 21 Oct 2021 07:34:55 +0000 (08:34 +0100)]
cachefiles: Implement a function to get/create a directory in the cache

Implement a function to get/create structural directories in the cache.
This is used for setting up a cache and creating volume substructures.  The
directory in memory are marked with the S_KERNEL_FILE inode flag whilst
they're in use to tell rmdir to reject attempts to remove them.

Changes
=======
ver #3:
 - Return an indication as to whether the directory was freshly created.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819631182.215744.3322471539523262619.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906933130.143852.962088616746509062.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967141952.1823006.7832985646370603833.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021542169.640689.18266858945694357839.stgit@warthog.procyon.org.uk/
2 years agovfs, cachefiles: Mark a backing file in use with an inode flag
David Howells [Thu, 18 Nov 2021 08:58:08 +0000 (08:58 +0000)]
vfs, cachefiles: Mark a backing file in use with an inode flag

Use an inode flag, S_KERNEL_FILE, to mark that a backing file is in use by
the kernel to prevent cachefiles or other kernel services from interfering
with that file.

Alter rmdir to reject attempts to remove a directory marked with this flag.
This is used by cachefiles to prevent cachefilesd from removing them.

Using S_SWAPFILE instead isn't really viable as that has other effects in
the I/O paths.

Changes
=======
ver #3:
 - Check for the object pointer being NULL in the tracepoints rather than
   the caller.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819630256.215744.4815885535039369574.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906931596.143852.8642051223094013028.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967141000.1823006.12920680657559677789.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021541207.640689.564689725898537127.stgit@warthog.procyon.org.uk/
2 years agocachefiles: Provide a function to check how much space there is
David Howells [Thu, 21 Oct 2021 07:59:46 +0000 (08:59 +0100)]
cachefiles: Provide a function to check how much space there is

Provide a function to check how much space there is.  This also flips the
state on the cache and will signal the daemon to inform it of the change
and to ask it to do some culling if necessary.

We will also need to subtract the amount of data currently being written to
the cache (cache->b_writing) from the amount of available space to avoid
hitting ENOSPC accidentally.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819629322.215744.13457425294680841213.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906930100.143852.1681026700865762069.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967140058.1823006.7781243664702837128.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021539957.640689.12477177372616805706.stgit@warthog.procyon.org.uk/
2 years agocachefiles: Register a miscdev and parse commands over it
David Howells [Fri, 26 Nov 2021 15:12:07 +0000 (15:12 +0000)]
cachefiles: Register a miscdev and parse commands over it

Register a misc device with which to talk to the daemon.  The misc device
holds a cache set up through it around and closing the device kills the
cache.

cachefilesd communicates with the kernel by passing it single-line text
commands.  Parse these and use them to parameterise the cache state.  This
does not implement the command to actually bring a cache online.  That's
left for later.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819628388.215744.17712097043607299608.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906929128.143852.14065207858943654011.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967139085.1823006.3514846391807454287.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021538400.640689.9172006906288062041.stgit@warthog.procyon.org.uk/
2 years agocachefiles: Add security derivation
David Howells [Fri, 26 Nov 2021 14:59:10 +0000 (14:59 +0000)]
cachefiles: Add security derivation

Implement code to derive a new set of creds for the cachefiles to use when
making VFS or I/O calls and to change the auditing info since the
application interacting with the network filesystem is not accessing the
cache directly.  Cachefiles uses override_creds() to change the effective
creds temporarily.

set_security_override_from_ctx() is called to derive the LSM 'label' that
the cachefiles driver will act with.  set_create_files_as() is called to
determine the LSM 'label' that will be applied to files and directories
created in the cache.  These functions alter the new creds.

Also implement a couple of functions to wrap the calls to begin/end cred
overriding.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819627469.215744.3603633690679962985.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906928172.143852.15886637013364286786.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967138138.1823006.7620933448261939504.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021537001.640689.4081334436031700558.stgit@warthog.procyon.org.uk/
2 years agocachefiles: Add cache error reporting macro
David Howells [Thu, 21 Oct 2021 08:08:54 +0000 (09:08 +0100)]
cachefiles: Add cache error reporting macro

Add a macro to report a cache I/O error and to tell fscache that the cache
is in trouble.

Also add a pointer to the fscache cache cookie from the cachefiles_cache
struct as we need that to pass to fscache_io_error().

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819626562.215744.1503690975344731661.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906927235.143852.13694625647880837563.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967137158.1823006.2065038830569321335.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021536053.640689.5306822604644352548.stgit@warthog.procyon.org.uk/
2 years agocachefiles: Add a couple of tracepoints for logging errors
David Howells [Thu, 21 Oct 2021 07:42:18 +0000 (08:42 +0100)]
cachefiles: Add a couple of tracepoints for logging errors

Add two trace points to log errors, one for vfs operations like mkdir or
create, and one for I/O operations, like read, write or truncate.

Also add the beginnings of a struct that is going to represent a data file
and place a debugging ID in it for the tracepoints to record.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819625632.215744.17907340966178411033.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906926297.143852.18267924605548658911.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967135390.1823006.2512120406360156424.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021534029.640689.1875723624947577095.stgit@warthog.procyon.org.uk/
2 years agocachefiles: Add some error injection support
David Howells [Thu, 21 Oct 2021 07:15:26 +0000 (08:15 +0100)]
cachefiles: Add some error injection support

Add support for injecting ENOSPC or EIO errors.  This needs to be enabled
by CONFIG_CACHEFILES_ERROR_INJECTION=y.  Once enabled, ENOSPC on things
like write and mkdir can be triggered by:

        echo 1 >/proc/sys/cachefiles/error_injection

and EIO can be triggered on most operations by:

        echo 2 >/proc/sys/cachefiles/error_injection

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819624706.215744.6911916249119962943.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906925343.143852.5465695512984025812.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967134412.1823006.7354285948280296595.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021532340.640689.18209494225772443698.stgit@warthog.procyon.org.uk/
2 years agocachefiles: Define structs
David Howells [Fri, 26 Nov 2021 14:45:38 +0000 (14:45 +0000)]
cachefiles: Define structs

Define the cachefiles_cache struct that's going to carry the cache-level
parameters and state of a cache.

Define the beginning of the cachefiles_object struct that's going to carry
the state for a data storage object.  For the moment this is just a
debugging ID for logging purposes.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819623690.215744.2824739137193655547.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906924292.143852.15881439716653984905.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967131405.1823006.4480555941533935597.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021530610.640689.846094074334176928.stgit@warthog.procyon.org.uk/
2 years agocachefiles: Introduce rewritten driver
David Howells [Fri, 26 Nov 2021 14:32:29 +0000 (14:32 +0000)]
cachefiles: Introduce rewritten driver

Introduce basic skeleton of the rewritten cachefiles driver including
config options so that it can be enabled for compilation.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819622766.215744.9108359326983195047.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906923341.143852.3856498104256721447.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967130320.1823006.15791456613198441566.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021528993.640689.9069695476048171884.stgit@warthog.procyon.org.uk/
2 years agofscache: Provide a function to resize a cookie
David Howells [Wed, 20 Oct 2021 13:06:34 +0000 (14:06 +0100)]
fscache: Provide a function to resize a cookie

Provide a function to change the size of the storage attached to a cookie,
to match the size of the file being cached when it's changed by truncate or
fallocate:

void fscache_resize_cookie(struct fscache_cookie *cookie,
   loff_t new_size);

This acts synchronously and is expected to run under the inode lock of the
caller.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819621839.215744.7895597119803515402.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906922387.143852.16394459879816147793.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967128998.1823006.10740669081985775576.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021527861.640689.3466382085497236267.stgit@warthog.procyon.org.uk/
2 years agofscache: Provide a function to note the release of a page
David Howells [Wed, 20 Oct 2021 13:06:34 +0000 (14:06 +0100)]
fscache: Provide a function to note the release of a page

Provide a function to be called from a network filesystem's releasepage
method to indicate that a page has been released that might have been a
reflection of data upon the server - and now that data must be reloaded
from the server or the cache.

This is used to end an optimisation for empty files, in particular files
that have just been created locally, whereby we know there cannot yet be
any data that we would need to read from the server or the cache.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819617128.215744.4725572296135656508.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906920354.143852.7511819614661372008.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967128061.1823006.611781655060034988.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021525963.640689.9264556596205140044.stgit@warthog.procyon.org.uk/
2 years agovfs, fscache: Implement pinning of cache usage for writeback
David Howells [Wed, 20 Oct 2021 22:50:01 +0000 (23:50 +0100)]
vfs, fscache: Implement pinning of cache usage for writeback

Cachefiles has a problem in that it needs to keep the backing file for a
cookie open whilst there are local modifications pending that need to be
written to it.  However, we don't want to keep the file open indefinitely,
as that causes EMFILE/ENFILE/ENOMEM problems.

Reopening the cache file, however, is a problem if this is being done due
to writeback triggered by exit().  Some filesystems will oops if we try to
open a file in that context because they want to access current->fs or
other resources that have already been dismantled.

To get around this, I added the following:

 (1) An inode flag, I_PINNING_FSCACHE_WB, to be set on a network filesystem
     inode to indicate that we have a usage count on the cookie caching
     that inode.

 (2) A flag in struct writeback_control, unpinned_fscache_wb, that is set
     when __writeback_single_inode() clears the last dirty page from
     i_pages - at which point it clears I_PINNING_FSCACHE_WB and sets this
     flag.

     This has to be done here so that clearing I_PINNING_FSCACHE_WB can be
     done atomically with the check of PAGECACHE_TAG_DIRTY that clears
     I_DIRTY_PAGES.

 (3) A function, fscache_set_page_dirty(), which if it is not set, sets
     I_PINNING_FSCACHE_WB and calls fscache_use_cookie() to pin the cache
     resources.

 (4) A function, fscache_unpin_writeback(), to be called by ->write_inode()
     to unuse the cookie.

 (5) A function, fscache_clear_inode_writeback(), to be called when the
     inode is evicted, before clear_inode() is called.  This cleans up any
     lingering I_PINNING_FSCACHE_WB.

The network filesystem can then use these tools to make sure that
fscache_write_to_cache() can write locally modified data to the cache as
well as to the server.

For the future, I'm working on write helpers for netfs lib that should
allow this facility to be removed by keeping track of the dirty regions
separately - but that's incomplete at the moment and is also going to be
affected by folios, one way or another, since it deals with pages

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819615157.215744.17623791756928043114.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906917856.143852.8224898306177154573.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967124567.1823006.14188359004568060298.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021524705.640689.17824932021727663017.stgit@warthog.procyon.org.uk/
2 years agofscache: Implement higher-level write I/O interface
David Howells [Wed, 20 Oct 2021 13:06:34 +0000 (14:06 +0100)]
fscache: Implement higher-level write I/O interface

Provide a higher-level function than fscache_write() to perform a write
from an inode's pagecache to the cache, whilst fending off concurrent
writes by means of the PG_fscache mark on a page:

void fscache_write_to_cache(struct fscache_cookie *cookie,
    struct address_space *mapping,
    loff_t start,
    size_t len,
    loff_t i_size,
    netfs_io_terminated_t term_func,
    void *term_func_priv,
    bool caching);

If caching is false, this function does nothing except call (*term_func)()
if given.  It assumes that, in such a case, PG_fscache will not have been
set on the pages.

Otherwise, if caching is true, this function requires the source pages to
have had PG_fscache set on them before calling.  start and len define the
region of the file to be modified and i_size indicates the new file size.
The source pages are extracted from the mapping.

term_func and term_func_priv work as for fscache_write().  The PG_fscache
marks will be cleared at the end of the operation, before term_func is
called or the function otherwise returns.

There is an additonal helper function to clear the PG_fscache bits from a
range of pages:

void fscache_clear_page_bits(struct fscache_cookie *cookie,
     struct address_space *mapping,
     loff_t start, size_t len,
     bool caching);

If caching is true, the pages to be managed are expected to be located on
mapping in the range defined by start and len.  If caching is false, it
does nothing.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819614155.215744.5528123235123721230.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906916346.143852.15632773570362489926.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967123599.1823006.12946816026724657428.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021522672.640689.4381958316198807813.stgit@warthog.procyon.org.uk/
2 years agofscache: Implement raw I/O interface
David Howells [Wed, 20 Oct 2021 13:06:34 +0000 (14:06 +0100)]
fscache: Implement raw I/O interface

Provide a pair of functions to perform raw I/O on the cache.  The first
function allows an arbitrary asynchronous direct-IO read to be made against
a cache object, though the read should be aligned and sized appropriately
for the backing device:

        int fscache_read(struct netfs_cache_resources *cres,
                         loff_t start_pos,
                         struct iov_iter *iter,
                         enum netfs_read_from_hole read_hole,
                         netfs_io_terminated_t term_func,
                         void *term_func_priv);

The cache resources must have been previously initialised by
fscache_begin_read_operation().  A read operation is sent to the backing
filesystem, starting at start_pos within the file.  The size of the read is
specified by the iterator, as is the location of the output buffer.

If there is a hole in the data it can be ignored and left to the backing
filesystem to deal with (NETFS_READ_HOLE_IGNORE), a hole at the beginning
can be skipped over and the buffer padded with zeros
(NETFS_READ_HOLE_CLEAR) or -ENODATA can be given (NETFS_READ_HOLE_FAIL).

If term_func is not NULL, the operation may be performed asynchronously.
Upon completion, successful or otherwise, (*term_func)() will be called and
passed term_func_priv, along with an error or the amount of data
transferred.  If the op is run asynchronously, fscache_read() will return
-EIOCBQUEUED.

The second function allows an arbitrary asynchronous direct-IO write to be
made against a cache object, though the write should be aligned and sized
appropriately for the backing device:

        int fscache_write(struct netfs_cache_resources *cres,
                          loff_t start_pos,
                          struct iov_iter *iter,
                          netfs_io_terminated_t term_func,
                          void *term_func_priv);

This works in very similar way to fscache_read(), except that there's no
need to deal with holes (they're just overwritten).

The caller is responsible for preventing concurrent overlapping writes.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819613224.215744.7877577215582621254.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906915386.143852.16936177636106480724.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967122632.1823006.7487049517698562172.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021521420.640689.12747258780542678309.stgit@warthog.procyon.org.uk/
2 years agonetfs: Pass more information on how to deal with a hole in the cache
David Howells [Tue, 14 Sep 2021 08:47:45 +0000 (09:47 +0100)]
netfs: Pass more information on how to deal with a hole in the cache

Pass more information to the cache on how to deal with a hole if it
encounters one when trying to read from the cache.  Three options are
provided:

 (1) NETFS_READ_HOLE_IGNORE.  Read the hole along with the data, assuming
     it to be a punched-out extent by the backing filesystem.

 (2) NETFS_READ_HOLE_CLEAR.  If there's a hole, erase the requested region
     of the cache and clear the read buffer.

 (3) NETFS_READ_HOLE_FAIL.  Fail the read if a hole is detected.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819612321.215744.9738308885948264476.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906914460.143852.6284247083607910189.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967119923.1823006.15637375885194297582.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021519762.640689.16994364383313159319.stgit@warthog.procyon.org.uk/
2 years agofscache: Provide a function to let the netfs update its coherency data
David Howells [Wed, 20 Oct 2021 22:10:46 +0000 (23:10 +0100)]
fscache: Provide a function to let the netfs update its coherency data

Provide a function to let the netfs update its coherency data:

void fscache_update_cookie(struct fscache_cookie *cookie,
   const void *aux_data,
   const loff_t *object_size);

This will update the auxiliary data and/or the size of the object attached
to a cookie if either pointer is not-NULL and flag that the disk needs to
be updated.

Note that fscache_unuse_cookie() also allows this to be done.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819610438.215744.4223265964131424954.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906913530.143852.18150303220217653820.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967117795.1823006.7493373142653442595.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021518440.640689.6369952464473039268.stgit@warthog.procyon.org.uk/
2 years agofscache: Provide read/write stat counters for the cache
David Howells [Wed, 20 Oct 2021 22:06:16 +0000 (23:06 +0100)]
fscache: Provide read/write stat counters for the cache

Provide read/write stat counters for the cache backend to use.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819609532.215744.10821082637727410554.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906912598.143852.12960327989649429069.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967113830.1823006.3222957649202368162.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021517502.640689.6077928311710357342.stgit@warthog.procyon.org.uk/
2 years agofscache: Count data storage objects in a cache
David Howells [Thu, 11 Nov 2021 23:14:29 +0000 (23:14 +0000)]
fscache: Count data storage objects in a cache

Count the data storage objects that are currently allocated in a cache.
This is used to pin certain cache structures until cache withdrawal is
complete.

Three helpers are provided to manage and make use of the count:

 (1) void fscache_count_object(struct fscache_cache *cache);

     This should be called by the cache backend to note that an object has
     been allocated and attached to the cache.

 (2) void fscache_uncount_object(struct fscache_cache *cache);

     This should be called by the backend to note that an object has been
     destroyed.  This sends a wakeup event that allows cache withdrawal to
     proceed if it was waiting for that object.

 (3) void fscache_wait_for_objects(struct fscache_cache *cache);

     This can be used by the backend to wait for all outstanding cache
     object to be destroyed.

Each cache's counter is displayed as part of /proc/fs/fscache/caches.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819608594.215744.1812706538117388252.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906911646.143852.168184059935530127.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967111846.1823006.9868154941573671255.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021516219.640689.4934796654308958158.stgit@warthog.procyon.org.uk/
2 years agofscache: Provide a means to begin an operation
David Howells [Wed, 20 Oct 2021 13:06:34 +0000 (14:06 +0100)]
fscache: Provide a means to begin an operation

Provide a function to begin a read operation:

int fscache_begin_read_operation(
struct netfs_cache_resources *cres,
struct fscache_cookie *cookie)

This is primarily intended to be called by network filesystems on behalf of
netfslib, but may also be called to use the I/O access functions directly.
It attaches the resources required by the cache to cres struct from the
supplied cookie.

This holds access to the cache behind the cookie for the duration of the
operation and forces cache withdrawal and cookie invalidation to perform
synchronisation on the operation.  cres->inval_counter is set from the
cookie at this point so that it can be compared at the end of the
operation.

Note that this does not guarantee that the cache state is fully set up and
able to perform I/O immediately; looking up and creation may be left in
progress in the background.  The operations intended to be called by the
network filesystem, such as reading and writing, are expected to wait for
the cookie to move to the correct state.

This will, however, potentially sleep, waiting for a certain minimum state
to be set or for operations such as invalidate to advance far enough that
I/O can resume.

Also provide a function for the cache to call to wait for the cache object
to get to a state where it can be used for certain things:

bool fscache_wait_for_operation(struct netfs_cache_resources *cres,
enum fscache_want_stage stage);

This looks at the cache resources provided by the begin function and waits
for them to get to an appropriate stage.  There's a choice of wanting just
some parameters (FSCACHE_WANT_PARAM) or the ability to do I/O
(FSCACHE_WANT_READ or FSCACHE_WANT_WRITE).

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819603692.215744.146724961588817028.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906910672.143852.13856103384424986357.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967110245.1823006.2239170567540431836.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021513617.640689.16627329360866150606.stgit@warthog.procyon.org.uk/
2 years agofscache: Implement cookie invalidation
David Howells [Wed, 20 Oct 2021 14:53:34 +0000 (15:53 +0100)]
fscache: Implement cookie invalidation

Add a function to invalidate the cache behind a cookie:

void fscache_invalidate(struct fscache_cookie *cookie,
const void *aux_data,
loff_t size,
unsigned int flags)

This causes any cached data for the specified cookie to be discarded.  If
the cookie is marked as being in use, a new cache object will be created if
possible and future I/O will use that instead.  In-flight I/O should be
abandoned (writes) or reconsidered (reads).  Each time it is called
cookie->inval_counter is incremented and this can be used to detect
invalidation at the end of an I/O operation.

The coherency data attached to the cookie can be updated and the cookie
size should be reset.  One flag is available, FSCACHE_INVAL_DIO_WRITE,
which should be used to indicate invalidation due to a DIO write on a
file.  This will temporarily disable caching for this cookie.

Changes
=======
ver #2:
 - Should only change to inval state if can get access to cache.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819602231.215744.11206598147269491575.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906909707.143852.18056070560477964891.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967107447.1823006.5945029409592119962.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021512640.640689.11418616313147754172.stgit@warthog.procyon.org.uk/
2 years agofscache: Implement cookie user counting and resource pinning
David Howells [Wed, 20 Oct 2021 14:53:34 +0000 (15:53 +0100)]
fscache: Implement cookie user counting and resource pinning

Provide a pair of functions to count the number of users of a cookie (open
files, writeback, invalidation, resizing, reads, writes), to obtain and pin
resources for the cookie and to prevent culling for the whilst there are
users.

The first function marks a cookie as being in use:

void fscache_use_cookie(struct fscache_cookie *cookie,
bool will_modify);

The caller should indicate the cookie to use and whether or not the caller
is in a context that may modify the cookie (e.g. a file open O_RDWR).

If the cookie is not already resourced, fscache will ask the cache backend
in the background to do whatever it needs to look up, create or otherwise
obtain the resources necessary to access data.  This is pinned to the
cookie and may not be culled, though it may be withdrawn if the cache as a
whole is withdrawn.

The second function removes the in-use mark from a cookie and, optionally,
updates the coherency data:

void fscache_unuse_cookie(struct fscache_cookie *cookie,
  const void *aux_data,
  const loff_t *object_size);

If non-NULL, the aux_data buffer and/or the object_size will be saved into
the cookie and will be set on the backing store when the object is
committed.

If this removes the last usage on a cookie, the cookie is placed onto an
LRU list from which it will be removed and closed after a couple of seconds
if it doesn't get reused.  This prevents resource overload in the cache -
in particular it prevents it from holding too many files open.

Changes
=======
ver #2:
 - Fix fscache_unuse_cookie() to use atomic_dec_and_lock() to avoid a
   potential race if the cookie gets reused before it completes the
   unusement.
 - Added missing transition to LRU_DISCARDING state.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819600612.215744.13678350304176542741.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906907567.143852.16979631199380722019.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967106467.1823006.6790864931048582667.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021511674.640689.10084988363699111860.stgit@warthog.procyon.org.uk/
2 years agofscache: Implement simple cookie state machine
David Howells [Wed, 20 Oct 2021 14:53:34 +0000 (15:53 +0100)]
fscache: Implement simple cookie state machine

Implement a very simple cookie state machine to handle lookup,
invalidation, withdrawal, relinquishment and, to be added later, commit on
LRU discard.

Three cache methods are provided: ->lookup_cookie() to look up and, if
necessary, create a data storage object; ->withdraw_cookie() to free the
resources associated with that object and potentially delete it; and
->prepare_to_write(), to do prepare for changes to the cached data to be
modified locally.

Changes
=======
ver #3:
 - Fix a race between LRU discard and relinquishment whereby the former
   would override the latter and thus the latter would never happen[1].

ver #2:
 - Don't hold n_accesses elevated whilst cache is bound to a cookie, but
   rather add a flag that prevents the state machine from being queued when
   n_accesses reaches 0.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/599331.1639410068@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163819599657.215744.15799615296912341745.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906903925.143852.1805855338154353867.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967105456.1823006.14730395299835841776.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021510706.640689.7961423370243272583.stgit@warthog.procyon.org.uk/
2 years agofscache: Add a function for a cache backend to note an I/O error
David Howells [Wed, 20 Oct 2021 14:00:26 +0000 (15:00 +0100)]
fscache: Add a function for a cache backend to note an I/O error

Add a function to the backend API to note an I/O error in a cache.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819598741.215744.891281275151382095.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906901316.143852.15225412215771586528.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967100721.1823006.16435671567428949398.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021508840.640689.11902836226570620424.stgit@warthog.procyon.org.uk/
2 years agofscache: Provide and use cache methods to lookup/create/free a volume
David Howells [Wed, 20 Oct 2021 14:26:17 +0000 (15:26 +0100)]
fscache: Provide and use cache methods to lookup/create/free a volume

Add cache methods to lookup, create and remove a volume.

Looking up or creating the volume requires the cache pinning for access;
freeing the volume requires the volume pinning for access.  The
->acquire_volume() method is used to ask the cache backend to lookup and,
if necessary, create a volume; the ->free_volume() method is used to free
the resources for a volume.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819597821.215744.5225318658134989949.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906898645.143852.8537799955945956818.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967099771.1823006.1455197910571061835.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021507345.640689.4073511598838843040.stgit@warthog.procyon.org.uk/
2 years agofscache: Implement functions add/remove a cache
David Howells [Wed, 20 Oct 2021 14:00:26 +0000 (15:00 +0100)]
fscache: Implement functions add/remove a cache

Implement functions to allow the cache backend to add or remove a cache:

 (1) Declare a cache to be live:

int fscache_add_cache(struct fscache_cache *cache,
      const struct fscache_cache_ops *ops,
      void *cache_priv);

     Take a previously acquired cache cookie, set the operations table and
     private data and mark the cache open for access.

 (2) Withdraw a cache from service:

void fscache_withdraw_cache(struct fscache_cache *cache);

     This marks the cache as withdrawn and thus prevents further
     cache-level and volume-level accesses.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819596022.215744.8799712491432238827.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906896599.143852.17049208999019262884.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967097870.1823006.3470041000971522030.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021505541.640689.1819714759326331054.stgit@warthog.procyon.org.uk/
2 years agofscache: Implement cookie-level access helpers
David Howells [Wed, 20 Oct 2021 14:53:34 +0000 (15:53 +0100)]
fscache: Implement cookie-level access helpers

Add a number of helper functions to manage access to a cookie, pinning the
cache object in place for the duration to prevent cache withdrawal from
removing it:

 (1) void fscache_init_access_gate(struct fscache_cookie *cookie);

     This function initialises the access count when a cache binds to a
     cookie.  An extra ref is taken on the access count to prevent wakeups
     while the cache is active.  We're only interested in the wakeup when a
     cookie is being withdrawn and we're waiting for it to quiesce - at
     which point the counter will be decremented before the wait.

     The FSCACHE_COOKIE_NACC_ELEVATED flag is set on the cookie to keep
     track of the extra ref in order to handle a race between
     relinquishment and withdrawal both trying to drop the extra ref.

 (2) bool fscache_begin_cookie_access(struct fscache_cookie *cookie,
      enum fscache_access_trace why);

     This function attempts to begin access upon a cookie, pinning it in
     place if it's cached.  If successful, it returns true and leaves a the
     access count incremented.

 (3) void fscache_end_cookie_access(struct fscache_cookie *cookie,
    enum fscache_access_trace why);

     This function drops the access count obtained by (2), permitting
     object withdrawal to take place when it reaches zero.

A tracepoint is provided to track changes to the access counter on a
cookie.

Changes
=======
ver #2:
 - Don't hold n_accesses elevated whilst cache is bound to a cookie, but
   rather add a flag that prevents the state machine from being queued when
   n_accesses reaches 0.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819595085.215744.1706073049250505427.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906895313.143852.10141619544149102193.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967095980.1823006.1133648159424418877.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021503063.640689.8870918985269528670.stgit@warthog.procyon.org.uk/
2 years agofscache: Implement volume-level access helpers
David Howells [Wed, 20 Oct 2021 14:26:17 +0000 (15:26 +0100)]
fscache: Implement volume-level access helpers

Add a pair of helper functions to manage access to a volume, pinning the
volume in place for the duration to prevent cache withdrawal from removing
it:

bool fscache_begin_volume_access(struct fscache_volume *volume,
 enum fscache_access_trace why);
void fscache_end_volume_access(struct fscache_volume *volume,
       enum fscache_access_trace why);

The way the access gate on the volume works/will work is:

  (1) If the cache tests as not live (state is not FSCACHE_CACHE_IS_ACTIVE),
      then we return false to indicate access was not permitted.

  (2) If the cache tests as live, then we increment the volume's n_accesses
      count and then recheck the cache liveness, ending the access if it
      ceased to be live.

  (3) When we end the access, we decrement the volume's n_accesses and wake
      up the any waiters if it reaches 0.

  (4) Whilst the cache is caching, the volume's n_accesses is kept
      artificially incremented to prevent wakeups from happening.

  (5) When the cache is taken offline, the state is changed to prevent new
      accesses, the volume's n_accesses is decremented and we wait for it to
      become 0.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819594158.215744.8285859817391683254.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906894315.143852.5454793807544710479.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967095028.1823006.9173132503876627466.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021501546.640689.9631510472149608443.stgit@warthog.procyon.org.uk/
2 years agofscache: Implement cache-level access helpers
David Howells [Wed, 20 Oct 2021 14:00:26 +0000 (15:00 +0100)]
fscache: Implement cache-level access helpers

Add a pair of functions to pin/unpin a cache that we're wanting to do a
high-level access to (such as creating or removing a volume):

bool fscache_begin_cache_access(struct fscache_cache *cache,
enum fscache_access_trace why);
void fscache_end_cache_access(struct fscache_cache *cache,
      enum fscache_access_trace why);

The way the access gate works/will work is:

 (1) If the cache tests as not live (state is not FSCACHE_CACHE_IS_ACTIVE),
     then we return false to indicate access was not permitted.

 (2) If the cache tests as live, then we increment the n_accesses count and
     then recheck the liveness, ending the access if it ceased to be live.

 (3) When we end the access, we decrement n_accesses and wake up the any
     waiters if it reaches 0.

 (4) Whilst the cache is caching, n_accesses is kept artificially
     incremented to prevent wakeups from happening.

 (5) When the cache is taken offline, the state is changed to prevent new
     accesses, n_accesses is decremented and we wait for n_accesses to
     become 0.

Note that some of this is implemented in a later patch.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819593239.215744.7537428720603638088.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906893368.143852.14164004598465617981.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967093977.1823006.6967886507023056409.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021499995.640689.18286203753480287850.stgit@warthog.procyon.org.uk/
2 years agofscache: Implement cookie registration
David Howells [Wed, 20 Oct 2021 14:53:34 +0000 (15:53 +0100)]
fscache: Implement cookie registration

Add functions to the fscache API to allow data file cookies to be acquired
and relinquished by the network filesystem.  It is intended that the
filesystem will create such cookies per-inode under a volume.

To request a cookie, the filesystem should call:

struct fscache_cookie *
fscache_acquire_cookie(struct fscache_volume *volume,
       u8 advice,
       const void *index_key,
       size_t index_key_len,
       const void *aux_data,
       size_t aux_data_len,
       loff_t object_size)

The filesystem must first have created a volume cookie, which is passed in
here.  If it passes in NULL then the function will just return a NULL
cookie.

A binary key should be passed in index_key and is of size index_key_len.
This is saved in the cookie and is used to locate the associated data in
the cache.

A coherency data buffer of size aux_data_len will be allocated and
initialised from the buffer pointed to by aux_data.  This is used to
validate cache objects when they're opened and is stored on disk with them
when they're committed.  The data is stored in the cookie and will be
updateable by various functions in later patches.

The object_size must also be given.  This is also used to perform a
coherency check and to size the backing storage appropriately.

This function disallows a cookie from being acquired twice in parallel,
though it will cause the second user to wait if the first is busy
relinquishing its cookie.

When a network filesystem has finished with a cookie, it should call:

void
fscache_relinquish_cookie(struct fscache_volume *volume,
  bool retire)

If retire is true, any backing data will be discarded immediately.

Changes
=======
ver #3:
 - fscache_hash()'s size parameter is now in bytes.  Use __le32 as the unit
   to round up to.
 - When comparing cookies, simply see if the attributes are the same rather
   than subtracting them to produce a strcmp-style return[1].
 - Add a check to see if the cookie is still hashed at the point of
   freeing.

ver #2:
 - Don't hold n_accesses elevated whilst cache is bound to a cookie, but
   rather add a flag that prevents the state machine from being queued when
   n_accesses reaches 0.
 - Remove the unused cookie pointer field from the fscache_acquire
   tracepoint.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/CAHk-=whtkzB446+hX0zdLsdcUJsJ=8_-0S1mE_R+YurThfUbLA@mail.gmail.com/
Link: https://lore.kernel.org/r/163819590658.215744.14934902514281054323.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906891983.143852.6219772337558577395.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967088507.1823006.12659006350221417165.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021498432.640689.12743483856927722772.stgit@warthog.procyon.org.uk/
2 years agofscache: Implement volume registration
David Howells [Wed, 20 Oct 2021 14:26:17 +0000 (15:26 +0100)]
fscache: Implement volume registration

Add functions to the fscache API to allow volumes to be acquired and
relinquished by the network filesystem.  A volume is an index of data
storage cache objects.  A volume is represented by a volume cookie in the
API.  A filesystem would typically create a volume for a superblock and
then create per-inode cookies within it.

To request a volume, the filesystem calls:

struct fscache_volume *
fscache_acquire_volume(const char *volume_key,
       const char *cache_name,
       const void *coherency_data,
       size_t coherency_len)

The volume_key is a printable string used to match the volume in the cache.
It should not contain any '/' characters.  For AFS, for example, this would
be "afs,<cellname>,<volume_id>", e.g. "afs,example.com,523001".

The cache_name can be NULL, but if not it should be a string indicating the
name of the cache to use if there's more than one available.

The coherency data, if given, is an arbitrarily-sized blob that's attached
to the volume and is compared when the volume is looked up.  If it doesn't
match, the old volume is judged to be out of date and it and everything
within it is discarded.

Acquiring a volume twice concurrently is disallowed, though the function
will wait if an old volume cookie is being relinquishing.

When a network filesystem has finished with a volume, it should return the
volume cookie by calling:

void
fscache_relinquish_volume(struct fscache_volume *volume,
  const void *coherency_data,
  bool invalidate)

If invalidate is true, the entire volume will be discarded; if false, the
volume will be synced and the coherency data will be updated.

Changes
=======
ver #4:
 - Removed an extraneous param from kdoc on fscache_relinquish_volume()[3].

ver #3:
 - fscache_hash()'s size parameter is now in bytes.  Use __le32 as the unit
   to round up to.
 - When comparing cookies, simply see if the attributes are the same rather
   than subtracting them to produce a strcmp-style return[2].
 - Make the coherency data an arbitrary blob rather than a u64, but don't
   store it for the moment.

ver #2:
 - Fix error check[1].
 - Make a fscache_acquire_volume() return errors, including EBUSY if a
   conflicting volume cookie already exists.  No error is printed now -
   that's left to the netfs.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/20211203095608.GC2480@kili/
Link: https://lore.kernel.org/r/CAHk-=whtkzB446+hX0zdLsdcUJsJ=8_-0S1mE_R+YurThfUbLA@mail.gmail.com/
Link: https://lore.kernel.org/r/20211220224646.30e8205c@canb.auug.org.au/
Link: https://lore.kernel.org/r/163819588944.215744.1629085755564865996.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906890630.143852.13972180614535611154.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967086836.1823006.8191672796841981763.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021495816.640689.4403156093668590217.stgit@warthog.procyon.org.uk/
2 years agofscache: Implement cache registration
David Howells [Wed, 20 Oct 2021 14:00:26 +0000 (15:00 +0100)]
fscache: Implement cache registration

Implement a register of caches and provide functions to manage it.

Two functions are provided for the cache backend to use:

 (1) Acquire a cache cookie:

struct fscache_cache *fscache_acquire_cache(const char *name)

     This gets the cache cookie for a cache of the specified name and moves
     it to the preparation state.  If a nameless cache cookie exists, that
     will be given this name and used.

 (2) Relinquish a cache cookie:

void fscache_relinquish_cache(struct fscache_cache *cache);

     This relinquishes a cache cookie, cleans it and makes it available if
     it's still referenced by a network filesystem.

Note that network filesystems don't deal with cache cookies directly, but
rather go straight to the volume registration.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819587157.215744.13523139317322503286.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906889665.143852.10378009165231294456.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967085081.1823006.2218944206363626210.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021494847.640689.10109692261640524343.stgit@warthog.procyon.org.uk/
2 years agofscache: Implement a hash function
David Howells [Wed, 20 Oct 2021 14:45:28 +0000 (15:45 +0100)]
fscache: Implement a hash function

Implement a function to generate hashes.  It needs to be stable over time
and endianness-independent as the hashes will appear on disk in future
patches.  It can assume that its input is a multiple of four bytes in size
and alignment.

This is borrowed from the VFS and simplified.  le32_to_cpu() is added to
make it endianness-independent.

Changes
=======
ver #3:
 - Read the data being hashed in an endianness-independent way[1].
 - Change the size parameter to be in bytes rather than words.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/CAHk-=whtkzB446+hX0zdLsdcUJsJ=8_-0S1mE_R+YurThfUbLA@mail.gmail.com
Link: https://lore.kernel.org/r/163819586113.215744.1699465806130102367.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906888735.143852.10944614318596881429.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967082342.1823006.8915671045444488742.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021493624.640689.9990442668811178628.stgit@warthog.procyon.org.uk/
2 years agofscache: Introduce new driver
David Howells [Wed, 20 Oct 2021 13:34:41 +0000 (14:34 +0100)]
fscache: Introduce new driver

Introduce basic skeleton of the new, rewritten fscache driver.

Changes
=======
ver #3:
 - Use remove_proc_subtree(), not remove_proc_entry() to remove a populated
   dir.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819584034.215744.4290533472390439030.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906887770.143852.3577888294989185666.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967080039.1823006.5702921801104057922.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021491014.640689.4292699878317589512.stgit@warthog.procyon.org.uk/
2 years agonetfs: Pass a flag to ->prepare_write() to say if there's no alloc'd space
David Howells [Wed, 20 Oct 2021 13:30:37 +0000 (14:30 +0100)]
netfs: Pass a flag to ->prepare_write() to say if there's no alloc'd space

Pass a flag to ->prepare_write() to indicate if there's definitely no
space allocated in the cache yet (for instance if we've already checked as
we were asked to do a read).

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819583123.215744.12783808230464471417.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906886835.143852.6689886781122679769.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967079100.1823006.12889542712309574359.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021489334.640689.3131206613015409076.stgit@warthog.procyon.org.uk/
2 years agonetfs: Display the netfs inode number in the netfs_read tracepoint
David Howells [Tue, 12 Oct 2021 11:05:27 +0000 (12:05 +0100)]
netfs: Display the netfs inode number in the netfs_read tracepoint

Display the netfs inode number in the netfs_read tracepoint so that this
can be used to correlate with the cachefiles_prep_read tracepoint.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819581097.215744.17476611915583897051.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906885903.143852.12229407815154182247.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967078164.1823006.15286989199782861123.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021487412.640689.7544388469390936443.stgit@warthog.procyon.org.uk/
2 years agofscache: Remove the contents of the fscache driver, pending rewrite
David Howells [Mon, 25 Oct 2021 20:53:44 +0000 (21:53 +0100)]
fscache: Remove the contents of the fscache driver, pending rewrite

Remove the code that comprises the fscache driver as it's going to be
substantially rewritten, with the majority of the code being erased in the
rewrite.

A small piece of linux/fscache.h is left as that is #included by a bunch of
network filesystems.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819578724.215744.18210619052245724238.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906884814.143852.6727245089843862889.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967077097.1823006.1377665951499979089.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021485548.640689.13876080567388696162.stgit@warthog.procyon.org.uk/
2 years agocachefiles: Delete the cachefiles driver pending rewrite
David Howells [Sun, 31 Oct 2021 12:58:05 +0000 (12:58 +0000)]
cachefiles: Delete the cachefiles driver pending rewrite

Delete the code from the cachefiles driver to make it easier to rewrite and
resubmit in a logical manner.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819577641.215744.12718114397770666596.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906883770.143852.4149714614981373410.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967076066.1823006.7175712134577687753.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021483619.640689.7586546280515844702.stgit@warthog.procyon.org.uk/
2 years agofscache, cachefiles: Disable configuration
David Howells [Mon, 25 Oct 2021 20:41:26 +0000 (21:41 +0100)]
fscache, cachefiles: Disable configuration

Disable fscache and cachefiles in Kconfig whilst it is rewritten.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819576672.215744.12444272479560406780.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906882835.143852.11073015983885872901.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967075113.1823006.277316290062782998.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021481179.640689.2004199594774033658.stgit@warthog.procyon.org.uk/
2 years agonetfs: fix parameter of cleanup()
Jeffle Xu [Tue, 7 Dec 2021 03:14:49 +0000 (11:14 +0800)]
netfs: fix parameter of cleanup()

The order of these two parameters is just reversed. gcc didn't warn on
that, probably because 'void *' can be converted from or to other
pointer types without warning.

Cc: stable@vger.kernel.org
Fixes: 3d3c95046742 ("netfs: Provide readahead and readpage netfs helpers")
Fixes: e1b1240c1ff5 ("netfs: Add write_begin helper")
Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Link: https://lore.kernel.org/r/20211207031449.100510-1-jefflexu@linux.alibaba.com/
2 years agonetfs: Fix lockdep warning from taking sb_writers whilst holding mmap_lock
David Howells [Tue, 7 Dec 2021 09:53:24 +0000 (09:53 +0000)]
netfs: Fix lockdep warning from taking sb_writers whilst holding mmap_lock

Taking sb_writers whilst holding mmap_lock isn't allowed and will result in
a lockdep warning like that below.  The problem comes from cachefiles
needing to take the sb_writers lock in order to do a write to the cache,
but being asked to do this by netfslib called from readpage, readahead or
write_begin[1].

Fix this by always offloading the write to the cache off to a worker
thread.  The main thread doesn't need to wait for it, so deadlock can be
avoided.

This can be tested by running the quick xfstests on something like afs or
ceph with lockdep enabled.

WARNING: possible circular locking dependency detected
5.15.0-rc1-build2+ #292 Not tainted
------------------------------------------------------
holetest/65517 is trying to acquire lock:
ffff88810c81d730 (mapping.invalidate_lock#3){.+.+}-{3:3}, at: filemap_fault+0x276/0x7a5

but task is already holding lock:
ffff8881595b53e8 (&mm->mmap_lock#2){++++}-{3:3}, at: do_user_addr_fault+0x28d/0x59c

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #2 (&mm->mmap_lock#2){++++}-{3:3}:
       validate_chain+0x3c4/0x4a8
       __lock_acquire+0x89d/0x949
       lock_acquire+0x2dc/0x34b
       __might_fault+0x87/0xb1
       strncpy_from_user+0x25/0x18c
       removexattr+0x7c/0xe5
       __do_sys_fremovexattr+0x73/0x96
       do_syscall_64+0x67/0x7a
       entry_SYSCALL_64_after_hwframe+0x44/0xae

-> #1 (sb_writers#10){.+.+}-{0:0}:
       validate_chain+0x3c4/0x4a8
       __lock_acquire+0x89d/0x949
       lock_acquire+0x2dc/0x34b
       cachefiles_write+0x2b3/0x4bb
       netfs_rreq_do_write_to_cache+0x3b5/0x432
       netfs_readpage+0x2de/0x39d
       filemap_read_page+0x51/0x94
       filemap_get_pages+0x26f/0x413
       filemap_read+0x182/0x427
       new_sync_read+0xf0/0x161
       vfs_read+0x118/0x16e
       ksys_read+0xb8/0x12e
       do_syscall_64+0x67/0x7a
       entry_SYSCALL_64_after_hwframe+0x44/0xae

-> #0 (mapping.invalidate_lock#3){.+.+}-{3:3}:
       check_noncircular+0xe4/0x129
       check_prev_add+0x16b/0x3a4
       validate_chain+0x3c4/0x4a8
       __lock_acquire+0x89d/0x949
       lock_acquire+0x2dc/0x34b
       down_read+0x40/0x4a
       filemap_fault+0x276/0x7a5
       __do_fault+0x96/0xbf
       do_fault+0x262/0x35a
       __handle_mm_fault+0x171/0x1b5
       handle_mm_fault+0x12a/0x233
       do_user_addr_fault+0x3d2/0x59c
       exc_page_fault+0x85/0xa5
       asm_exc_page_fault+0x1e/0x30

other info that might help us debug this:

Chain exists of:
  mapping.invalidate_lock#3 --> sb_writers#10 --> &mm->mmap_lock#2

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&mm->mmap_lock#2);
                               lock(sb_writers#10);
                               lock(&mm->mmap_lock#2);
  lock(mapping.invalidate_lock#3);

 *** DEADLOCK ***

1 lock held by holetest/65517:
 #0: ffff8881595b53e8 (&mm->mmap_lock#2){++++}-{3:3}, at: do_user_addr_fault+0x28d/0x59c

stack backtrace:
CPU: 0 PID: 65517 Comm: holetest Not tainted 5.15.0-rc1-build2+ #292
Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014
Call Trace:
 dump_stack_lvl+0x45/0x59
 check_noncircular+0xe4/0x129
 ? print_circular_bug+0x207/0x207
 ? validate_chain+0x461/0x4a8
 ? add_chain_block+0x88/0xd9
 ? hlist_add_head_rcu+0x49/0x53
 check_prev_add+0x16b/0x3a4
 validate_chain+0x3c4/0x4a8
 ? check_prev_add+0x3a4/0x3a4
 ? mark_lock+0xa5/0x1c6
 __lock_acquire+0x89d/0x949
 lock_acquire+0x2dc/0x34b
 ? filemap_fault+0x276/0x7a5
 ? rcu_read_unlock+0x59/0x59
 ? add_to_page_cache_lru+0x13c/0x13c
 ? lock_is_held_type+0x7b/0xd3
 down_read+0x40/0x4a
 ? filemap_fault+0x276/0x7a5
 filemap_fault+0x276/0x7a5
 ? pagecache_get_page+0x2dd/0x2dd
 ? __lock_acquire+0x8bc/0x949
 ? pte_offset_kernel.isra.0+0x6d/0xc3
 __do_fault+0x96/0xbf
 ? do_fault+0x124/0x35a
 do_fault+0x262/0x35a
 ? handle_pte_fault+0x1c1/0x20d
 __handle_mm_fault+0x171/0x1b5
 ? handle_pte_fault+0x20d/0x20d
 ? __lock_release+0x151/0x254
 ? mark_held_locks+0x1f/0x78
 ? rcu_read_unlock+0x3a/0x59
 handle_mm_fault+0x12a/0x233
 do_user_addr_fault+0x3d2/0x59c
 ? pgtable_bad+0x70/0x70
 ? rcu_read_lock_bh_held+0xab/0xab
 exc_page_fault+0x85/0xa5
 ? asm_exc_page_fault+0x8/0x30
 asm_exc_page_fault+0x1e/0x30
RIP: 0033:0x40192f
Code: ff 48 89 c3 48 8b 05 50 28 00 00 48 85 ed 7e 23 31 d2 4b 8d 0c 2f eb 0a 0f 1f 00 48 8b 05 39 28 00 00 48 0f af c2 48 83 c2 01 <48> 89 1c 01 48 39 d5 7f e8 8b 0d f2 27 00 00 31 c0 85 c9 74 0e 8b
RSP: 002b:00007f9931867eb0 EFLAGS: 00010202
RAX: 0000000000000000 RBX: 00007f9931868700 RCX: 00007f993206ac00
RDX: 0000000000000001 RSI: 0000000000000000 RDI: 00007ffc13e06ee0
RBP: 0000000000000100 R08: 0000000000000000 R09: 00007f9931868700
R10: 00007f99318689d0 R11: 0000000000000202 R12: 00007ffc13e06ee0
R13: 0000000000000c00 R14: 00007ffc13e06e00 R15: 00007f993206a000

Fixes: 726218fdc22c ("netfs: Define an interface to talk to a cache")
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Jeff Layton <jlayton@kernel.org>
cc: Jan Kara <jack@suse.cz>
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/20210922110420.GA21576@quack2.suse.cz/
Link: https://lore.kernel.org/r/163887597541.1596626.2668163316598972956.stgit@warthog.procyon.org.uk/
2 years agoLinux 5.16-rc4
Linus Torvalds [Sun, 5 Dec 2021 22:08:22 +0000 (14:08 -0800)]
Linux 5.16-rc4

2 years agoMerge tag 'for-5.16/parisc-6' of git://git.kernel.org/pub/scm/linux/kernel/git/deller...
Linus Torvalds [Sun, 5 Dec 2021 20:58:18 +0000 (12:58 -0800)]
Merge tag 'for-5.16/parisc-6' of git://git./linux/kernel/git/deller/parisc-linux

Pull parisc fixes from Helge Deller:
 "Some bug and warning fixes:

   - Fix "make install" to use debians "installkernel" script which is
     now in /usr/sbin

   - Fix the bindeb-pkg make target by giving the correct KBUILD_IMAGE
     file name

   - Fix compiler warnings by annotating parisc agp init functions with
     __init

   - Fix timekeeping on SMP machines with dual-core CPUs

   - Enable some more config options in the 64-bit defconfig"

* tag 'for-5.16/parisc-6' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Mark cr16 CPU clocksource unstable on all SMP machines
  parisc: Fix "make install" on newer debian releases
  parisc/agp: Annotate parisc agp init functions with __init
  parisc: Enable sata sil, audit and usb support on 64-bit defconfig
  parisc: Fix KBUILD_IMAGE for self-extracting kernel

2 years agoMerge tag 'usb-5.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Linus Torvalds [Sun, 5 Dec 2021 17:34:57 +0000 (09:34 -0800)]
Merge tag 'usb-5.16-rc4' of git://git./linux/kernel/git/gregkh/usb

Pull USB fixes from Greg KH:
 "Here are some small USB fixes for a few reported issues. Included in
  here are:

   - xhci fix for a _much_ reported regression. I don't think there's a
     community distro that has not reported this problem yet :(

   - new USB quirk addition

   - cdns3 minor fixes

   - typec regression fix.

  All of these have been in linux-next with no reported problems, and
  the xhci fix has been reported by many to resolve their reported
  problem"

* tag 'usb-5.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  usb: cdnsp: Fix a NULL pointer dereference in cdnsp_endpoint_init()
  usb: cdns3: gadget: fix new urb never complete if ep cancel previous requests
  usb: typec: tcpm: Wait in SNK_DEBOUNCED until disconnect
  USB: NO_LPM quirk Lenovo Powered USB-C Travel Hub
  xhci: Fix commad ring abort, write all 64 bits to CRCR register.

2 years agoMerge tag 'tty-5.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Linus Torvalds [Sun, 5 Dec 2021 17:13:20 +0000 (09:13 -0800)]
Merge tag 'tty-5.16-rc4' of git://git./linux/kernel/git/gregkh/tty

Pull tty/serial fixes from Greg KH:
 "Here are some small TTY and Serial driver fixes for 5.16-rc4 to
  resolve a number of reported problems.

  They include:

   - liteuart serial driver fixes

   - 8250_pci serial driver fixes for pericom devices

   - 8250 RTS line control fix while in RS-485 mode

   - tegra serial driver fix

   - msm_serial driver fix

   - pl011 serial driver new id

   - fsl_lpuart revert of broken change

   - 8250_bcm7271 serial driver fix

   - MAINTAINERS file update for rpmsg tty driver that came in 5.16-rc1

   - vgacon fix for reported problem

  All of these, except for the 8250_bcm7271 fix have been in linux-next
  with no reported problem. The 8250_bcm7271 fix was added to the tree
  on Friday so no chance to be linux-next yet. But it should be fine as
  the affected developers submitted it"

* tag 'tty-5.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  serial: 8250_bcm7271: UART errors after resuming from S2
  serial: 8250_pci: rewrite pericom_do_set_divisor()
  serial: 8250_pci: Fix ACCES entries in pci_serial_quirks array
  serial: 8250: Fix RTS modem control while in rs485 mode
  Revert "tty: serial: fsl_lpuart: drop earlycon entry for i.MX8QXP"
  serial: tegra: Change lower tolerance baud rate limit for tegra20 and tegra30
  serial: liteuart: relax compile-test dependencies
  serial: liteuart: fix minor-number leak on probe errors
  serial: liteuart: fix use-after-free and memleak on unbind
  serial: liteuart: Fix NULL pointer dereference in ->remove()
  vgacon: Propagate console boot parameters before calling `vc_resize'
  tty: serial: msm_serial: Deactivate RX DMA for polling support
  serial: pl011: Add ACPI SBSA UART match id
  serial: core: fix transmit-buffer reset and memleak
  MAINTAINERS: Add rpmsg tty driver maintainer

2 years agoMerge tag 'timers_urgent_for_v5.16_rc4' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Sun, 5 Dec 2021 16:58:52 +0000 (08:58 -0800)]
Merge tag 'timers_urgent_for_v5.16_rc4' of git://git./linux/kernel/git/tip/tip

Pull timer fix from Borislav Petkov:

 - Prevent a tick storm when a dedicated timekeeper CPU in nohz_full
   mode runs for prolonged periods with interrupts disabled and ends up
   programming the next tick in the past, leading to that storm

* tag 'timers_urgent_for_v5.16_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  timers/nohz: Last resort update jiffies on nohz_full IRQ entry

2 years agoMerge tag 'sched_urgent_for_v5.16_rc4' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Sun, 5 Dec 2021 16:53:31 +0000 (08:53 -0800)]
Merge tag 'sched_urgent_for_v5.16_rc4' of git://git./linux/kernel/git/tip/tip

Pull scheduler fixes from Borislav Petkov:

 - Properly init uclamp_flags of a runqueue, on first enqueuing

 - Fix preempt= callback return values

 - Correct utime/stime resource usage reporting on nohz_full to return
   the proper times instead of shorter ones

* tag 'sched_urgent_for_v5.16_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/uclamp: Fix rq->uclamp_max not set on first enqueue
  preempt/dynamic: Fix setup_preempt_mode() return value
  sched/cputime: Fix getrusage(RUSAGE_THREAD) with nohz_full

2 years agoMerge tag 'x86_urgent_for_v5.16_rc4' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Sun, 5 Dec 2021 16:43:35 +0000 (08:43 -0800)]
Merge tag 'x86_urgent_for_v5.16_rc4' of git://git./linux/kernel/git/tip/tip

Pull x86 fixes from Borislav Petkov:

 - Fix a couple of SWAPGS fencing issues in the x86 entry code

 - Use the proper operand types in __{get,put}_user() to prevent
   truncation in SEV-ES string io

 - Make sure the kernel mappings are present in trampoline_pgd in order
   to prevent any potential accesses to unmapped memory after switching
   to it

 - Fix a trivial list corruption in objtool's pv_ops validation

 - Disable the clocksource watchdog for TSC on platforms which claim
   that the TSC is constant, doesn't stop in sleep states, CPU has TSC
   adjust and the number of sockets of the platform are max 2, to
   prevent erroneous markings of the TSC as unstable.

 - Make sure TSC adjust is always checked not only when going idle

 - Prevent a stack leak by initializing struct _fpx_sw_bytes properly in
   the FPU code

 - Fix INTEL_FAM6_RAPTORLAKE define naming to adhere to the convention

* tag 'x86_urgent_for_v5.16_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/xen: Add xenpv_restore_regs_and_return_to_usermode()
  x86/entry: Use the correct fence macro after swapgs in kernel CR3
  x86/entry: Add a fence for kernel entry SWAPGS in paranoid_entry()
  x86/sev: Fix SEV-ES INS/OUTS instructions for word, dword, and qword
  x86/64/mm: Map all kernel memory into trampoline_pgd
  objtool: Fix pv_ops noinstr validation
  x86/tsc: Disable clocksource watchdog for TSC on qualified platorms
  x86/tsc: Add a timer to make sure TSC_adjust is always checked
  x86/fpu/signal: Initialize sw_bytes in save_xstate_epilog()
  x86/cpu: Drop spurious underscore from RAPTOR_LAKE #define

2 years agoMerge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Linus Torvalds [Sun, 5 Dec 2021 16:25:33 +0000 (08:25 -0800)]
Merge tag 'for-linus' of git://git./virt/kvm/kvm

Pull more kvm fixes from Paolo Bonzini:

 - Static analysis fix

 - New SEV-ES protocol for communicating invalid VMGEXIT requests

 - Ensure APICv is considered inactive if there is no APIC

 - Fix reserved bits for AMD PerfEvtSeln register

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: SVM: Do not terminate SEV-ES guests on GHCB validation failure
  KVM: SEV: Fall back to vmalloc for SEV-ES scratch area if necessary
  KVM: SEV: Return appropriate error codes if SEV-ES scratch setup fails
  KVM: x86/mmu: Retry page fault if root is invalidated by memslot update
  KVM: VMX: Set failure code in prepare_vmcs02()
  KVM: ensure APICv is considered inactive if there is no APIC
  KVM: x86/pmu: Fix reserved bits for AMD PerfEvtSeln register

2 years agoKVM: SVM: Do not terminate SEV-ES guests on GHCB validation failure
Tom Lendacky [Thu, 2 Dec 2021 18:52:05 +0000 (12:52 -0600)]
KVM: SVM: Do not terminate SEV-ES guests on GHCB validation failure

Currently, an SEV-ES guest is terminated if the validation of the VMGEXIT
exit code or exit parameters fails.

The VMGEXIT instruction can be issued from userspace, even though
userspace (likely) can't update the GHCB. To prevent userspace from being
able to kill the guest, return an error through the GHCB when validation
fails rather than terminating the guest. For cases where the GHCB can't be
updated (e.g. the GHCB can't be mapped, etc.), just return back to the
guest.

The new error codes are documented in the lasest update to the GHCB
specification.

Fixes: 291bd20d5d88 ("KVM: SVM: Add initial support for a VMGEXIT VMEXIT")
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-Id: <b57280b5562893e2616257ac9c2d4525a9aeeb42.1638471124.git.thomas.lendacky@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2 years agoKVM: SEV: Fall back to vmalloc for SEV-ES scratch area if necessary
Sean Christopherson [Tue, 9 Nov 2021 22:23:50 +0000 (22:23 +0000)]
KVM: SEV: Fall back to vmalloc for SEV-ES scratch area if necessary

Use kvzalloc() to allocate KVM's buffer for SEV-ES's GHCB scratch area so
that KVM falls back to __vmalloc() if physically contiguous memory isn't
available.  The buffer is purely a KVM software construct, i.e. there's
no need for it to be physically contiguous.

Cc: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211109222350.2266045-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2 years agoKVM: SEV: Return appropriate error codes if SEV-ES scratch setup fails
Sean Christopherson [Tue, 9 Nov 2021 22:23:49 +0000 (22:23 +0000)]
KVM: SEV: Return appropriate error codes if SEV-ES scratch setup fails

Return appropriate error codes if setting up the GHCB scratch area for an
SEV-ES guest fails.  In particular, returning -EINVAL instead of -ENOMEM
when allocating the kernel buffer could be confusing as userspace would
likely suspect a guest issue.

Fixes: 8f423a80d299 ("KVM: SVM: Support MMIO for an SEV-ES guest")
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211109222350.2266045-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2 years agoMerge tag 'xfs-5.16-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Linus Torvalds [Sun, 5 Dec 2021 01:22:53 +0000 (17:22 -0800)]
Merge tag 'xfs-5.16-fixes-2' of git://git./fs/xfs/xfs-linux

Pull xfs fix from Darrick Wong:
 "Remove an unnecessary (and backwards) rename flags check that
  duplicates a VFS level check"

* tag 'xfs-5.16-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: remove incorrect ASSERT in xfs_rename

2 years agoMerge tag '5.16-rc3-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6
Linus Torvalds [Sat, 4 Dec 2021 21:43:52 +0000 (13:43 -0800)]
Merge tag '5.16-rc3-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6

Pull cifs fixes from Steve French:
 "Three SMB3 multichannel/fscache fixes and a DFS fix.

  In testing multichannel reconnect scenarios recently various problems
  with the cifs.ko implementation of fscache were found (e.g. incorrect
  initialization of fscache cookies in some cases)"

* tag '5.16-rc3-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: avoid use of dstaddr as key for fscache client cookie
  cifs: add server conn_id to fscache client cookie
  cifs: wait for tcon resource_id before getting fscache super
  cifs: fix missed refcounting of ipc tcon

2 years agoparisc: Mark cr16 CPU clocksource unstable on all SMP machines
Helge Deller [Sat, 4 Dec 2021 20:21:46 +0000 (21:21 +0100)]
parisc: Mark cr16 CPU clocksource unstable on all SMP machines

In commit c8c3735997a3 ("parisc: Enhance detection of synchronous cr16
clocksources") I assumed that CPUs on the same physical core are syncronous.
While booting up the kernel on two different C8000 machines, one with a
dual-core PA8800 and one with a dual-core PA8900 CPU, this turned out to be
wrong. The symptom was that I saw a jump in the internal clocks printed to the
syslog and strange overall behaviour.  On machines which have 4 cores (2
dual-cores) the problem isn't visible, because the current logic already marked
the cr16 clocksource unstable in this case.

This patch now marks the cr16 interval timers unstable if we have more than one
CPU in the system, and it fixes this issue.

Fixes: c8c3735997a3 ("parisc: Enhance detection of synchronous cr16 clocksources")
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org> # v5.15+
2 years agoparisc: Fix "make install" on newer debian releases
Helge Deller [Sat, 4 Dec 2021 20:14:40 +0000 (21:14 +0100)]
parisc: Fix "make install" on newer debian releases

On newer debian releases the debian-provided "installkernel" script is
installed in /usr/sbin. Fix the kernel install.sh script to look for the
script in this directory as well.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org> # v3.13+
2 years agoMerge tag 'block-5.16-2021-12-03' of git://git.kernel.dk/linux-block
Linus Torvalds [Sat, 4 Dec 2021 16:38:25 +0000 (08:38 -0800)]
Merge tag 'block-5.16-2021-12-03' of git://git.kernel.dk/linux-block

Pull block fix from Jens Axboe:
 "A single fix for repeated printk spam from loop"

* tag 'block-5.16-2021-12-03' of git://git.kernel.dk/linux-block:
  loop: Use pr_warn_once() for loop_control_remove() warning

2 years agoMerge tag 'io_uring-5.16-2021-12-03' of git://git.kernel.dk/linux-block
Linus Torvalds [Sat, 4 Dec 2021 16:34:59 +0000 (08:34 -0800)]
Merge tag 'io_uring-5.16-2021-12-03' of git://git.kernel.dk/linux-block

Pull io_uring fix from Jens Axboe:
 "Just a single fix preventing repeated retries of task_work based io-wq
  thread creation, fixing a regression from when io-wq was made more (a
  bit too much) resilient against signals"

* tag 'io_uring-5.16-2021-12-03' of git://git.kernel.dk/linux-block:
  io-wq: don't retry task_work creation failure on fatal conditions

2 years agoMerge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Linus Torvalds [Sat, 4 Dec 2021 16:28:42 +0000 (08:28 -0800)]
Merge tag 'scsi-fixes' of git://git./linux/kernel/git/jejb/scsi

Pull SCSI fixes from James Bottomley:
 "Two patches, both in drivers.

  One is a fix to FC recovery (lpfc) and the other is an enhancement to
  support the Intel Alder Motherboard with the UFS driver which comes
  under the -rc exception process for hardware enabling"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: ufs: ufs-pci: Add support for Intel ADL
  scsi: lpfc: Fix non-recovery of remote ports following an unsolicited LOGO

2 years agoMerge tag 'gfs2-v5.16-rc4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Sat, 4 Dec 2021 16:13:20 +0000 (08:13 -0800)]
Merge tag 'gfs2-v5.16-rc4-fixes' of git://git./linux/kernel/git/gfs2/linux-gfs2

Pull gfs2 fixes from Andreas Gruenbacher:

 - Since commit 486408d690e1 ("gfs2: Cancel remote delete work
   asynchronously"), inode create and lookup-by-number can overlap more
   easily and we can end up with temporary duplicate inodes. Fix the
   code to prevent that.

 - Fix a BUG demoting weak glock holders from a remote node.

* tag 'gfs2-v5.16-rc4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  gfs2: gfs2_create_inode rework
  gfs2: gfs2_inode_lookup rework
  gfs2: gfs2_inode_lookup cleanup
  gfs2: Fix remote demote of weak glock holders

2 years agosched/uclamp: Fix rq->uclamp_max not set on first enqueue
Qais Yousef [Thu, 2 Dec 2021 11:20:33 +0000 (11:20 +0000)]
sched/uclamp: Fix rq->uclamp_max not set on first enqueue

Commit d81ae8aac85c ("sched/uclamp: Fix initialization of struct
uclamp_rq") introduced a bug where uclamp_max of the rq is not reset to
match the woken up task's uclamp_max when the rq is idle.

The code was relying on rq->uclamp_max initialized to zero, so on first
enqueue

static inline void uclamp_rq_inc_id(struct rq *rq, struct task_struct *p,
    enum uclamp_id clamp_id)
{
...

if (uc_se->value > READ_ONCE(uc_rq->value))
WRITE_ONCE(uc_rq->value, uc_se->value);
}

was actually resetting it. But since commit d81ae8aac85c changed the
default to 1024, this no longer works. And since rq->uclamp_flags is
also initialized to 0, neither above code path nor uclamp_idle_reset()
update the rq->uclamp_max on first wake up from idle.

This is only visible from first wake up(s) until the first dequeue to
idle after enabling the static key. And it only matters if the
uclamp_max of this task is < 1024 since only then its uclamp_max will be
effectively ignored.

Fix it by properly initializing rq->uclamp_flags = UCLAMP_FLAG_IDLE to
ensure uclamp_idle_reset() is called which then will update the rq
uclamp_max value as expected.

Fixes: d81ae8aac85c ("sched/uclamp: Fix initialization of struct uclamp_rq")
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <Valentin.Schneider@arm.com>
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Link: https://lkml.kernel.org/r/20211202112033.1705279-1-qais.yousef@arm.com
2 years agopreempt/dynamic: Fix setup_preempt_mode() return value
Andrew Halaney [Fri, 3 Dec 2021 23:32:03 +0000 (17:32 -0600)]
preempt/dynamic: Fix setup_preempt_mode() return value

__setup() callbacks expect 1 for success and 0 for failure. Correct the
usage here to reflect that.

Fixes: 826bfeb37bb4 ("preempt/dynamic: Support dynamic preempt with preempt= boot option")
Reported-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Andrew Halaney <ahalaney@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20211203233203.133581-1-ahalaney@redhat.com
2 years agoMerge tag 'vfio-v5.16-rc4' of git://github.com/awilliam/linux-vfio
Linus Torvalds [Fri, 3 Dec 2021 20:27:08 +0000 (12:27 -0800)]
Merge tag 'vfio-v5.16-rc4' of git://github.com/awilliam/linux-vfio

Pull VFIO fixes from Alex Williamson:

 - Fix OpRegion pointer arithmetic (Zhenyu Wang)

 - Fix comment format triggering kernel-doc warnings (Randy Dunlap)

* tag 'vfio-v5.16-rc4' of git://github.com/awilliam/linux-vfio:
  vfio/pci: Fix OpRegion read
  vfio: remove all kernel-doc notation

2 years agoMerge tag 'pm-5.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Linus Torvalds [Fri, 3 Dec 2021 20:22:56 +0000 (12:22 -0800)]
Merge tag 'pm-5.16-rc4' of git://git./linux/kernel/git/rafael/linux-pm

Pull power management fixes from Rafael Wysocki:
 "These fix a CPU hot-add issue in the cpufreq core, fix a comment in
  the cpufreq core code and update its documentation, and disable the
  DTPM (Dynamic Thermal Power Management) code for the time being to
  prevent it from causing issues to appear.

  Specifics:

   - Disable DTPM for this cycle to prevent it from causing issues to
     appear on otherwise functional systems (Daniel Lezcano)

   - Fix cpufreq sysfs interface failure related to physical CPU hot-add
     (Xiongfeng Wang)

   - Fix comment in cpufreq core and update its documentation (Tang
     Yizhou)"

* tag 'pm-5.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  powercap: DTPM: Drop unused local variable from init_dtpm()
  cpufreq: docs: Update core.rst
  cpufreq: Fix a comment in cpufreq_policy_free
  powercap/drivers/dtpm: Disable DTPM at boot time
  cpufreq: Fix get_cpu_device() failure in add_cpu_dev_symlink()

2 years agoMerge tag 's390-5.16-4' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Linus Torvalds [Fri, 3 Dec 2021 19:46:20 +0000 (11:46 -0800)]
Merge tag 's390-5.16-4' of git://git./linux/kernel/git/s390/linux

Pull s390 fixes from Heiko Carstens:

 - Fix potential overlap of pseudo-MMIO addresses with MIO addresses

 - Fix stack unwinder test case inline assembly compile error that
   happens with LLVM's integrated assembler

 - Update defconfigs

* tag 's390-5.16-4' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390: update defconfigs
  s390/pci: move pseudo-MMIO to prevent MIO overlap
  s390/test_unwind: use raw opcode instead of invalid instruction

2 years agoMerge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Linus Torvalds [Fri, 3 Dec 2021 18:50:14 +0000 (10:50 -0800)]
Merge tag 'arm64-fixes' of git://git./linux/kernel/git/arm64/linux

Pull arm64 fixes from Will Deacon:
 "Three arm64 fixes for -rc4.

  One of them is just a trivial documentation fix, whereas the other two
  address a warning in the kexec code and a crash in ftrace on systems
  implementing BTI.

  The latter patch has a couple of ugly ifdefs which Mark plans to clean
  up separately, but as-is the patch is straightforward for backporting
  to stable kernels.

  Summary:

   - Add missing BTI landing instructions to the ftrace*_caller
     trampolines

   - Fix kexec() WARN when DEBUG_VIRTUAL is enabled

   - Fix PAC documentation by removing stale references to compiler
     flags"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: ftrace: add missing BTIs
  arm64: kexec: use __pa_symbol(empty_zero_page)
  arm64: update PAC description for kernel

2 years agoMerge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa...
Linus Torvalds [Fri, 3 Dec 2021 18:44:16 +0000 (10:44 -0800)]
Merge branch 'i2c/for-current' of git://git./linux/kernel/git/wsa/linux

Pull i2c fixes from Wolfram Sang:
 "I2C has another set of driver bugfixes, mostly for the stm32f7 driver"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: rk3x: Handle a spurious start completion interrupt flag
  i2c: stm32f7: use proper DMAENGINE API for termination
  i2c: stm32f7: stop dma transfer in case of NACK
  i2c: stm32f7: recover the bus on access timeout
  i2c: stm32f7: flush TX FIFO upon transfer errors
  i2c: cbus-gpio: set atomic transfer callback

2 years agoMerge tag 'libata-5.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal...
Linus Torvalds [Fri, 3 Dec 2021 18:38:45 +0000 (10:38 -0800)]
Merge tag 'libata-5.16-rc4' of git://git./linux/kernel/git/dlemoal/libata

Pull libata fixes from Damien Le Moal:
 "Two sparse warning fixes and a couple of patches to fix an issue with
  sata_fsl driver module removal:

   - A couple of patches to avoid sparse warnings in libata-sata and in
     the pata_falcon driver (from Yang and Finn).

   - A couple of sata_fsl driver patches fixing IRQ free and proc
     unregister on module removal (from Baokun)"

* tag 'libata-5.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/libata:
  ata: replace snprintf in show functions with sysfs_emit
  sata_fsl: fix warning in remove_proc_entry when rmmod sata_fsl
  sata_fsl: fix UAF in sata_fsl_port_stop when rmmod sata_fsl
  pata_falcon: Avoid type warnings from sparse

2 years agocifs: avoid use of dstaddr as key for fscache client cookie
Shyam Prasad N [Thu, 2 Dec 2021 07:46:54 +0000 (07:46 +0000)]
cifs: avoid use of dstaddr as key for fscache client cookie

server->dstaddr can change when the DNS mapping for the
server hostname changes. But conn_id is a u64 counter
that is incremented each time a new TCP connection
is setup. So use only that as a key.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2 years agocifs: add server conn_id to fscache client cookie
Shyam Prasad N [Thu, 2 Dec 2021 07:30:00 +0000 (07:30 +0000)]
cifs: add server conn_id to fscache client cookie

The fscache client cookie uses the server address
(and port) as the cookie key. This is a problem when
nosharesock is used. Two different connections will
use duplicate cookies. Avoid this by adding
server->conn_id to the key, so that it's guaranteed
that cookie will not be duplicated.

Also, for secondary channels of a session, copy the
fscache pointer from the primary channel. The primary
channel is guaranteed not to go away as long as secondary
channels are in use.  Also addresses minor problem found
by kernel test robot.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2 years agocifs: wait for tcon resource_id before getting fscache super
Shyam Prasad N [Thu, 2 Dec 2021 07:14:42 +0000 (07:14 +0000)]
cifs: wait for tcon resource_id before getting fscache super

The logic for initializing tcon->resource_id is done inside
cifs_root_iget. fscache super cookie relies on this for aux
data. So we need to push the fscache initialization to this
later point during mount.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2 years agocifs: fix missed refcounting of ipc tcon
Paulo Alcantara [Thu, 2 Dec 2021 18:29:35 +0000 (15:29 -0300)]
cifs: fix missed refcounting of ipc tcon

Fix missed refcounting of IPC tcon used for getting domain-based DFS
root referrals.  We want to keep it alive as long as mount is active
and can be refreshed.  For standalone DFS root referrals it wouldn't
be a problem as the client ends up having an IPC tcon for both mount
and cache.

Fixes: c88f7dcd6d64 ("cifs: support nested dfs links over reconnect")
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
2 years agox86/xen: Add xenpv_restore_regs_and_return_to_usermode()
Lai Jiangshan [Fri, 26 Nov 2021 10:11:23 +0000 (18:11 +0800)]
x86/xen: Add xenpv_restore_regs_and_return_to_usermode()

In the native case, PER_CPU_VAR(cpu_tss_rw + TSS_sp0) is the
trampoline stack. But XEN pv doesn't use trampoline stack, so
PER_CPU_VAR(cpu_tss_rw + TSS_sp0) is also the kernel stack.

In that case, source and destination stacks are identical, which means
that reusing swapgs_restore_regs_and_return_to_usermode() in XEN pv
would cause %rsp to move up to the top of the kernel stack and leave the
IRET frame below %rsp.

This is dangerous as it can be corrupted if #NMI / #MC hit as either of
these events occurring in the middle of the stack pushing would clobber
data on the (original) stack.

And, with  XEN pv, swapgs_restore_regs_and_return_to_usermode() pushing
the IRET frame on to the original address is useless and error-prone
when there is any future attempt to modify the code.

 [ bp: Massage commit message. ]

Fixes: 7f2590a110b8 ("x86/entry/64: Use a per-CPU trampoline stack for IDT entries")
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lkml.kernel.org/r/20211126101209.8613-4-jiangshanlai@gmail.com
2 years agox86/entry: Use the correct fence macro after swapgs in kernel CR3
Lai Jiangshan [Fri, 26 Nov 2021 10:11:22 +0000 (18:11 +0800)]
x86/entry: Use the correct fence macro after swapgs in kernel CR3

The commit

  c75890700455 ("x86/entry/64: Remove unneeded kernel CR3 switching")

removed a CR3 write in the faulting path of load_gs_index().

But the path's FENCE_SWAPGS_USER_ENTRY has no fence operation if PTI is
enabled, see spectre_v1_select_mitigation().

Rather, it depended on the serializing CR3 write of SWITCH_TO_KERNEL_CR3
and since it got removed, add a FENCE_SWAPGS_KERNEL_ENTRY call to make
sure speculation is blocked.

 [ bp: Massage commit message and comment. ]

Fixes: c75890700455 ("x86/entry/64: Remove unneeded kernel CR3 switching")
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20211126101209.8613-3-jiangshanlai@gmail.com
2 years agofget: check that the fd still exists after getting a ref to it
Linus Torvalds [Wed, 1 Dec 2021 18:06:14 +0000 (10:06 -0800)]
fget: check that the fd still exists after getting a ref to it

Jann Horn points out that there is another possible race wrt Unix domain
socket garbage collection, somewhat reminiscent of the one fixed in
commit cbcf01128d0a ("af_unix: fix garbage collect vs MSG_PEEK").

See the extended comment about the garbage collection requirements added
to unix_peek_fds() by that commit for details.

The race comes from how we can locklessly look up a file descriptor just
as it is in the process of being closed, and with the right artificial
timing (Jann added a few strategic 'mdelay(500)' calls to do that), the
Unix domain socket garbage collector could see the reference count
decrement of the close() happen before fget() took its reference to the
file and the file was attached onto a new file descriptor.

This is all (intentionally) correct on the 'struct file *' side, with
RCU lookups and lockless reference counting very much part of the
design.  Getting that reference count out of order isn't a problem per
se.

But the garbage collector can get confused by seeing this situation of
having seen a file not having any remaining external references and then
seeing it being attached to an fd.

In commit cbcf01128d0a ("af_unix: fix garbage collect vs MSG_PEEK") the
fix was to serialize the file descriptor install with the garbage
collector by taking and releasing the unix_gc_lock.

That's not really an option here, but since this all happens when we are
in the process of looking up a file descriptor, we can instead simply
just re-check that the file hasn't been closed in the meantime, and just
re-do the lookup if we raced with a concurrent close() of the same file
descriptor.

Reported-and-tested-by: Jann Horn <jannh@google.com>
Acked-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agox86/entry: Add a fence for kernel entry SWAPGS in paranoid_entry()
Lai Jiangshan [Fri, 26 Nov 2021 10:11:21 +0000 (18:11 +0800)]
x86/entry: Add a fence for kernel entry SWAPGS in paranoid_entry()

Commit

  18ec54fdd6d18 ("x86/speculation: Prepare entry code for Spectre v1 swapgs mitigations")

added FENCE_SWAPGS_{KERNEL|USER}_ENTRY for conditional SWAPGS. In
paranoid_entry(), it uses only FENCE_SWAPGS_KERNEL_ENTRY for both
branches. This is because the fence is required for both cases since the
CR3 write is conditional even when PTI is enabled.

But

  96b2371413e8f ("x86/entry/64: Switch CR3 before SWAPGS in paranoid entry")

changed the order of SWAPGS and the CR3 write. And it missed the needed
FENCE_SWAPGS_KERNEL_ENTRY for the user gsbase case.

Add it back by changing the branches so that FENCE_SWAPGS_KERNEL_ENTRY
can cover both branches.

  [ bp: Massage, fix typos, remove obsolete comment while at it. ]

Fixes: 96b2371413e8f ("x86/entry/64: Switch CR3 before SWAPGS in paranoid entry")
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20211126101209.8613-2-jiangshanlai@gmail.com
2 years agoMerge branch 'powercap'
Rafael J. Wysocki [Fri, 3 Dec 2021 17:09:32 +0000 (18:09 +0100)]
Merge branch 'powercap'

Merge DTPM fixes for 5.16-rc4.

* powercap:
  powercap: DTPM: Drop unused local variable from init_dtpm()
  powercap/drivers/dtpm: Disable DTPM at boot time

2 years agox86/sev: Fix SEV-ES INS/OUTS instructions for word, dword, and qword
Michael Sterritt [Fri, 19 Nov 2021 23:27:57 +0000 (15:27 -0800)]
x86/sev: Fix SEV-ES INS/OUTS instructions for word, dword, and qword

Properly type the operands being passed to __put_user()/__get_user().
Otherwise, these routines truncate data for dependent instructions
(e.g., INSW) and only read/write one byte.

This has been tested by sending a string with REP OUTSW to a port and
then reading it back in with REP INSW on the same port.

Previous behavior was to only send and receive the first char of the
size. For example, word operations for "abcd" would only read/write
"ac". With change, the full string is now written and read back.

Fixes: f980f9c31a923 (x86/sev-es: Compile early handler code into kernel image)
Signed-off-by: Michael Sterritt <sterritt@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Marc Orr <marcorr@google.com>
Reviewed-by: Peter Gonda <pgonda@google.com>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
Link: https://lkml.kernel.org/r/20211119232757.176201-1-sterritt@google.com
2 years agopowercap: DTPM: Drop unused local variable from init_dtpm()
Rafael J. Wysocki [Fri, 3 Dec 2021 16:51:59 +0000 (17:51 +0100)]
powercap: DTPM: Drop unused local variable from init_dtpm()

The dtpm_descr variable in init_dtpm() is not used after commit
f751db8adaea ("powercap/drivers/dtpm: Disable DTPM at boot time"),
so drop it.

Fixes: f751db8adaea ("powercap/drivers/dtpm: Disable DTPM at boot time")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2 years agoio-wq: don't retry task_work creation failure on fatal conditions
Jens Axboe [Fri, 3 Dec 2021 02:40:15 +0000 (19:40 -0700)]
io-wq: don't retry task_work creation failure on fatal conditions

We don't want to be retrying task_work creation failure if there's
an actual signal pending for the parent task. If we do, then we can
enter an infinite loop of perpetually retrying and each retry failing
with -ERESTARTNOINTR because a signal is pending.

Fixes: 3146cba99aa2 ("io-wq: make worker creation resilient against signals")
Reported-by: Florian Fischer <florian.fl.fischer@fau.de>
Link: https://lore.kernel.org/io-uring/20211202165606.mqryio4yzubl7ms5@pasture/
Tested-by: Florian Fischer <florian.fl.fischer@fau.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2 years agoserial: 8250_bcm7271: UART errors after resuming from S2
Al Cooper [Wed, 1 Dec 2021 20:14:02 +0000 (15:14 -0500)]
serial: 8250_bcm7271: UART errors after resuming from S2

There is a small window in time during resume where the hardware
flow control signal RTS can be asserted (which allows a sender to
resume sending data to the UART) but the baud rate has not yet
been restored. This will cause corrupted data and FRAMING, OVERRUN
and BREAK errors. This is happening because the MCTRL register is
shadowed in uart_port struct and is later used during resume to set
the MCTRL register during both serial8250_do_startup() and
uart_resume_port(). Unfortunately, serial8250_do_startup()
happens before the UART baud rate is restored. The fix is to clear
the shadowed mctrl value at the end of suspend and restore it at the
end of resume.

Fixes: 41a469482de2 ("serial: 8250: Add new 8250-core based Broadcom STB driver")
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Al Cooper <alcooperx@gmail.com>
Link: https://lore.kernel.org/r/20211201201402.47446-1-alcooperx@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2 years agousb: cdnsp: Fix a NULL pointer dereference in cdnsp_endpoint_init()
Zhou Qingyang [Tue, 30 Nov 2021 17:27:00 +0000 (01:27 +0800)]
usb: cdnsp: Fix a NULL pointer dereference in cdnsp_endpoint_init()

In cdnsp_endpoint_init(), cdnsp_ring_alloc() is assigned to pep->ring
and there is a dereference of it in cdnsp_endpoint_init(), which could
lead to a NULL pointer dereference on failure of cdnsp_ring_alloc().

Fix this bug by adding a check of pep->ring.

This bug was found by a static analyzer. The analysis employs
differential checking to identify inconsistent security operations
(e.g., checks or kfrees) between two code paths and confirms that the
inconsistent operations are not recovered in the current function or
the callers, so they constitute bugs.

Note that, as a bug found by static analysis, it can be a false
positive or hard to trigger. Multiple researchers have cross-reviewed
the bug.

Builds with CONFIG_USB_CDNSP_GADGET=y show no new warnings,
and our static analyzer no longer warns about this code.

Fixes: 3d82904559f4 ("usb: cdnsp: cdns3 Add main part of Cadence USBSSP DRD Driver")
Cc: stable <stable@vger.kernel.org>
Acked-by: Pawel Laszczak <pawell@cadence.com>
Acked-by: Peter Chen <peter.chen@kernel.org>
Signed-off-by: Zhou Qingyang <zhou1615@umn.edu>
Link: https://lore.kernel.org/r/20211130172700.206650-1-zhou1615@umn.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2 years agousb: cdns3: gadget: fix new urb never complete if ep cancel previous requests
Frank Li [Tue, 30 Nov 2021 15:42:39 +0000 (09:42 -0600)]
usb: cdns3: gadget: fix new urb never complete if ep cancel previous requests

This issue was found at android12 MTP.
1. MTP submit many out urb request.
2. Cancel left requests (>20) when enough data get from host
3. Send ACK by IN endpoint.
4. MTP submit new out urb request.
5. 4's urb never complete.

TRACE LOG:

MtpServer-2157    [000] d..3  1287.150391: cdns3_ep_dequeue: ep1out: req: 00000000299e6836, req buff 000000009df42287, length: 0/16384 zsi, status: -115, trb: [start:87, end:87: virt addr 0x80004000ffd50420], flags:1 SID: 0
MtpServer-2157    [000] d..3  1287.150410: cdns3_gadget_giveback: ep1out: req: 00000000299e6836, req buff 000000009df42287, length: 0/16384 zsi, status: -104, trb: [start:87, end:87: virt addr 0x80004000ffd50420], flags:0 SID: 0
MtpServer-2157    [000] d..3  1287.150433: cdns3_ep_dequeue: ep1out: req: 0000000080b7bde6, req buff 000000009ed5c556, length: 0/16384 zsi, status: -115, trb: [start:88, end:88: virt addr 0x80004000ffd5042c], flags:1 SID: 0
MtpServer-2157    [000] d..3  1287.150446: cdns3_gadget_giveback: ep1out: req: 0000000080b7bde6, req buff 000000009ed5c556, length: 0/16384 zsi, status: -104, trb: [start:88, end:88: virt addr 0x80004000ffd5042c], flags:0 SID: 0
....
MtpServer-2157    [000] d..1  1293.630410: cdns3_alloc_request: ep1out: req: 00000000afbccb7d, req buff 0000000000000000, length: 0/0 zsi, status: 0, trb: [start:0, end:0: virt addr (null)], flags:0 SID: 0
MtpServer-2157    [000] d..2  1293.630421: cdns3_ep_queue: ep1out: req: 00000000afbccb7d, req buff 00000000871caf90, length: 0/512 zsi, status: -115, trb: [start:0, end:0: virt addr (null)], flags:0 SID: 0
MtpServer-2157    [000] d..2  1293.630445: cdns3_wa1: WA1: ep1out set guard
MtpServer-2157    [000] d..2  1293.630450: cdns3_wa1: WA1: ep1out restore cycle bit
MtpServer-2157    [000] d..2  1293.630453: cdns3_prepare_trb: ep1out: trb 000000007317b3ee, dma buf: 0xffd5bc00, size: 512, burst: 128 ctrl: 0x00000424 (C=0, T=0, ISP, IOC, Normal) SID:0 LAST_SID:0
MtpServer-2157    [000] d..2  1293.630460: cdns3_doorbell_epx: ep1out, ep_trbaddr ffd50414
....
irq/241-5b13000-2154    [000] d..1  1293.680849: cdns3_epx_irq: IRQ for ep1out: 01000408 ISP , ep_traddr: ffd508ac ep_last_sid: 00000000 use_streams: 0
irq/241-5b13000-2154    [000] d..1  1293.680858: cdns3_complete_trb: ep1out: trb 0000000021a11b54, dma buf: 0xffd50420, size: 16384, burst: 128 ctrl: 0x00001810 (C=0, T=0, CHAIN, LINK) SID:0 LAST_SID:0
irq/241-5b13000-2154    [000] d..1  1293.680865: cdns3_request_handled: Req: 00000000afbccb7d not handled, DMA pos: 185, ep deq: 88, ep enq: 185, start trb: 184, end trb: 184

Actually DMA pos already bigger than previous submit request afbccb7d's TRB (184-184). The reason of (not handled) is that deq position is wrong.

The TRB link is below when irq happen.

DEQ LINK LINK LINK LINK LINK .... TRB(afbccb7d):START  DMA(EP_TRADDR).

Original code check LINK TRB, but DEQ just move one step.

LINK DEQ LINK LINK LINK LINK .... TRB(afbccb7d):START  DMA(EP_TRADDR).

This patch skip all LINK TRB and sync DEQ to trb's start.

LINK LINK LINK LINK LINK .... DEQ = TRB(afbccb7d):START  DMA(EP_TRADDR).

Acked-by: Peter Chen <peter.chen@kernel.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Jun Li <jun.li@nxp.com>
Link: https://lore.kernel.org/r/20211130154239.8029-1-Frank.Li@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2 years agousb: typec: tcpm: Wait in SNK_DEBOUNCED until disconnect
Badhri Jagan Sridharan [Tue, 30 Nov 2021 00:18:25 +0000 (16:18 -0800)]
usb: typec: tcpm: Wait in SNK_DEBOUNCED until disconnect

Stub from the spec:
"4.5.2.2.4.2 Exiting from AttachWait.SNK State
A Sink shall transition to Unattached.SNK when the state of both
the CC1 and CC2 pins is SNK.Open for at least tPDDebounce.
A DRP shall transition to Unattached.SRC when the state of both
the CC1 and CC2 pins is SNK.Open for at least tPDDebounce."

This change makes TCPM to wait in SNK_DEBOUNCED state until
CC1 and CC2 pins is SNK.Open for at least tPDDebounce. Previously,
TCPM resets the port if vbus is not present in PD_T_PS_SOURCE_ON.
This causes TCPM to loop continuously when connected to a
faulty power source that does not present vbus. Waiting in
SNK_DEBOUNCED also ensures that TCPM is adherant to
"4.5.2.2.4.2 Exiting from AttachWait.SNK State" requirements.

[ 6169.280751] CC1: 0 -> 0, CC2: 0 -> 5 [state TOGGLING, polarity 0, connected]
[ 6169.280759] state change TOGGLING -> SNK_ATTACH_WAIT [rev2 NONE_AMS]
[ 6169.280771] pending state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED @ 170 ms [rev2 NONE_AMS]
[ 6169.282427] CC1: 0 -> 0, CC2: 5 -> 5 [state SNK_ATTACH_WAIT, polarity 0, connected]
[ 6169.450825] state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED [delayed 170 ms]
[ 6169.450834] pending state change SNK_DEBOUNCED -> PORT_RESET @ 480 ms [rev2 NONE_AMS]
[ 6169.930892] state change SNK_DEBOUNCED -> PORT_RESET [delayed 480 ms]
[ 6169.931296] disable vbus discharge ret:0
[ 6169.931301] Setting usb_comm capable false
[ 6169.932783] Setting voltage/current limit 0 mV 0 mA
[ 6169.932802] polarity 0
[ 6169.933706] Requesting mux state 0, usb-role 0, orientation 0
[ 6169.936689] cc:=0
[ 6169.936812] pending state change PORT_RESET -> PORT_RESET_WAIT_OFF @ 100 ms [rev2 NONE_AMS]
[ 6169.937157] CC1: 0 -> 0, CC2: 5 -> 0 [state PORT_RESET, polarity 0, disconnected]
[ 6170.036880] state change PORT_RESET -> PORT_RESET_WAIT_OFF [delayed 100 ms]
[ 6170.036890] state change PORT_RESET_WAIT_OFF -> SNK_UNATTACHED [rev2 NONE_AMS]
[ 6170.036896] Start toggling
[ 6170.041412] CC1: 0 -> 0, CC2: 0 -> 0 [state TOGGLING, polarity 0, disconnected]
[ 6170.042973] CC1: 0 -> 0, CC2: 0 -> 5 [state TOGGLING, polarity 0, connected]
[ 6170.042976] state change TOGGLING -> SNK_ATTACH_WAIT [rev2 NONE_AMS]
[ 6170.042981] pending state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED @ 170 ms [rev2 NONE_AMS]
[ 6170.213014] state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED [delayed 170 ms]
[ 6170.213019] pending state change SNK_DEBOUNCED -> PORT_RESET @ 480 ms [rev2 NONE_AMS]
[ 6170.693068] state change SNK_DEBOUNCED -> PORT_RESET [delayed 480 ms]
[ 6170.693304] disable vbus discharge ret:0
[ 6170.693308] Setting usb_comm capable false
[ 6170.695193] Setting voltage/current limit 0 mV 0 mA
[ 6170.695210] polarity 0
[ 6170.695990] Requesting mux state 0, usb-role 0, orientation 0
[ 6170.701896] cc:=0
[ 6170.702181] pending state change PORT_RESET -> PORT_RESET_WAIT_OFF @ 100 ms [rev2 NONE_AMS]
[ 6170.703343] CC1: 0 -> 0, CC2: 5 -> 0 [state PORT_RESET, polarity 0, disconnected]

Fixes: f0690a25a140b8 ("staging: typec: USB Type-C Port Manager (tcpm)")
Cc: stable@vger.kernel.org
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Badhri Jagan Sridharan <badhri@google.com>
Link: https://lore.kernel.org/r/20211130001825.3142830-1-badhri@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2 years agoUSB: NO_LPM quirk Lenovo Powered USB-C Travel Hub
Ole Ernst [Sat, 27 Nov 2021 09:05:45 +0000 (10:05 +0100)]
USB: NO_LPM quirk Lenovo Powered USB-C Travel Hub

This is another branded 8153 device that doesn't work well with LPM:
r8152 2-2.1:1.0 enp0s13f0u2u1: Stop submitting intr, status -71

Disable LPM to resolve the issue.

Signed-off-by: Ole Ernst <olebowle@gmx.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20211127090546.52072-1-olebowle@gmx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2 years agoxhci: Fix commad ring abort, write all 64 bits to CRCR register.
Mathias Nyman [Fri, 26 Nov 2021 12:23:40 +0000 (14:23 +0200)]
xhci: Fix commad ring abort, write all 64 bits to CRCR register.

Turns out some xHC controllers require all 64 bits in the CRCR register
to be written to execute a command abort.

The lower 32 bits containing the command abort bit is written first.
In case the command ring stops before we write the upper 32 bits then
hardware may use these upper bits to set the commnd ring dequeue pointer.

Solve this by making sure the upper 32 bits contain a valid command
ring dequeue pointer.

The original patch that only wrote the first 32 to stop the ring went
to stable, so this fix should go there as well.

Fixes: ff0e50d3564f ("xhci: Fix command ring pointer corruption while aborting a command")
Cc: stable@vger.kernel.org
Tested-by: Pavankumar Kondeti <quic_pkondeti@quicinc.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20211126122340.1193239-2-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2 years agox86/64/mm: Map all kernel memory into trampoline_pgd
Joerg Roedel [Thu, 2 Dec 2021 15:32:26 +0000 (16:32 +0100)]
x86/64/mm: Map all kernel memory into trampoline_pgd

The trampoline_pgd only maps the 0xfffffff000000000-0xffffffffffffffff
range of kernel memory (with 4-level paging). This range contains the
kernel's text+data+bss mappings and the module mapping space but not the
direct mapping and the vmalloc area.

This is enough to get the application processors out of real-mode, but
for code that switches back to real-mode the trampoline_pgd is missing
important parts of the address space. For example, consider this code
from arch/x86/kernel/reboot.c, function machine_real_restart() for a
64-bit kernel:

  #ifdef CONFIG_X86_32
   load_cr3(initial_page_table);
  #else
   write_cr3(real_mode_header->trampoline_pgd);

   /* Exiting long mode will fail if CR4.PCIDE is set. */
   if (boot_cpu_has(X86_FEATURE_PCID))
   cr4_clear_bits(X86_CR4_PCIDE);
  #endif

   /* Jump to the identity-mapped low memory code */
  #ifdef CONFIG_X86_32
   asm volatile("jmpl *%0" : :
        "rm" (real_mode_header->machine_real_restart_asm),
        "a" (type));
  #else
   asm volatile("ljmpl *%0" : :
        "m" (real_mode_header->machine_real_restart_asm),
        "D" (type));
  #endif

The code switches to the trampoline_pgd, which unmaps the direct mapping
and also the kernel stack. The call to cr4_clear_bits() will find no
stack and crash the machine. The real_mode_header pointer below points
into the direct mapping, and dereferencing it also causes a crash.

The reason this does not crash always is only that kernel mappings are
global and the CR3 switch does not flush those mappings. But if theses
mappings are not in the TLB already, the above code will crash before it
can jump to the real-mode stub.

Extend the trampoline_pgd to contain all kernel mappings to prevent
these crashes and to make code which runs on this page-table more
robust.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20211202153226.22946-5-joro@8bytes.org
2 years agoobjtool: Fix pv_ops noinstr validation
Peter Zijlstra [Thu, 2 Dec 2021 20:45:34 +0000 (21:45 +0100)]
objtool: Fix pv_ops noinstr validation

Boris reported that in one of his randconfig builds, objtool got
infinitely stuck. Turns out there's trivial list corruption in the
pv_ops tracking when a function is both in a static table and in a code
assignment.

Avoid re-adding function to the pv_ops[] lists when they're already on
it.

Fixes: db2b0c5d7b6f ("objtool: Support pv_opsindirect calls for noinstr")
Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Tested-by: Borislav Petkov <bp@alien8.de>
Link: https://lkml.kernel.org/r/20211202204534.GA16608@worktop.programming.kicks-ass.net
2 years agoMerge tag 'drm-fixes-2021-12-03-1' of git://anongit.freedesktop.org/drm/drm
Linus Torvalds [Thu, 2 Dec 2021 22:38:54 +0000 (14:38 -0800)]
Merge tag 'drm-fixes-2021-12-03-1' of git://anongit.freedesktop.org/drm/drm

Pull drm fixes from Dave Airlie:
 "Bit of an uptick in patch count this week, though it's all relatively
  small overall.

  I suspect msm has been queuing up a few fixes to skew it here.
  Otherwise amdgpu has a scattered bunch of small fixes, and then some
  vc4, i915.

  virtio-gpu changes an rc1 introduced uAPI mistake, and makes it
  operate more like other drivers. This should be fine as no userspace
  relies on the behaviour yet.

  Summary:

  dma-buf:
   - memory leak fix

  msm:
   - kasan found memory overwrite
   - mmap flags
   - fencing error bug
   - ioctl NULL ptr
   - uninit var
   - devfreqless devices fix
   - dsi lanes fix
   - dp: avoid unpowered aux xfers

  amdgpu:
   - IP discovery based enumeration fixes
   - vkms fixes
   - DSC fixes for DP MST
   - Audio fix for hotplug with tiled displays
   - Misc display fixes
   - DP tunneling fix
   - DP fix
   - Aldebaran fix

  amdkfd:
   - Locking fix
   - Static checker fix
   - Fix double free

  i915:
   - backlight regression
   - Intel HDR backlight detection fix
   - revert TGL workaround that caused hangs

  virtio-gpu:
   - switch back to drm_poll

  vc4:
   - memory leak
   - error check fix
   - HVS modesetting fixes"

* tag 'drm-fixes-2021-12-03-1' of git://anongit.freedesktop.org/drm/drm: (41 commits)
  Revert "drm/i915: Implement Wa_1508744258"
  drm/amdkfd: process_info lock not needed for svm
  drm/amdgpu: adjust the kfd reset sequence in reset sriov function
  drm/amd/display: add connector type check for CRC source set
  drm/amdkfd: fix double free mem structure
  drm/amdkfd: set "r = 0" explicitly before goto
  drm/amd/display: Add work around for tunneled MST.
  drm/amd/display: Fix for the no Audio bug with Tiled Displays
  drm/amd/display: Clear DPCD lane settings after repeater training
  drm/amd/display: Allow DSC on supported MST branch devices
  drm/amdgpu: Don't halt RLC on GFX suspend
  drm/amdgpu: fix the missed handling for SDMA2 and SDMA3
  drm/amdgpu: check atomic flag to differeniate with legacy path
  drm/amdgpu: cancel the correct hrtimer on exit
  drm/amdgpu/sriov/vcn: add new vcn ip revision check case for SIENNA_CICHLID
  drm/i915/dp: Perform 30ms delay after source OUI write
  dma-buf: system_heap: Use 'for_each_sgtable_sg' in pages free flow
  drm/i915: Add support for panels with VESA backlights with PWM enable/disable
  drm/vc4: kms: Fix previous HVS commit wait
  drm/vc4: kms: Don't duplicate pending commit
  ...

2 years agoMerge tag 'drm-intel-fixes-2021-12-02' of git://anongit.freedesktop.org/drm/drm-intel...
Dave Airlie [Thu, 2 Dec 2021 19:59:26 +0000 (05:59 +1000)]
Merge tag 'drm-intel-fixes-2021-12-02' of git://anongit.freedesktop.org/drm/drm-intel into drm-fixes

- Fixing a regression where the backlight brightness control stopped working.

- Fix the Intel HDR backlight support detection.

- Reverting a w/a to fix a gpu Hang in TGL. The w/a itself was also
for a hang, but in a much rarer scenario. The proper solution need
to be done with help from user space and it will be addressed later.

Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/Yakf9hdnR5or+zNP@intel.com
2 years agoMerge tag 'drm-misc-fixes-2021-12-02' of git://anongit.freedesktop.org/drm/drm-misc...
Dave Airlie [Thu, 2 Dec 2021 19:57:11 +0000 (05:57 +1000)]
Merge tag 'drm-misc-fixes-2021-12-02' of git://anongit.freedesktop.org/drm/drm-misc into drm-fixes

Switch back to drm_poll for virtio, multiple fixes (memory leak,
improper error check, some functional fixes too) for vc4, memory leak
fix in dma-buf,

Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20211202084440.u3b7lbeulj7k3ltg@houat
2 years agoMerge tag 'net-5.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Linus Torvalds [Thu, 2 Dec 2021 19:22:06 +0000 (11:22 -0800)]
Merge tag 'net-5.16-rc4' of git://git./linux/kernel/git/netdev/net

Pull networking fixes from Jakub Kicinski:
 "Including fixes from wireless, and wireguard.

  Mostly scattered driver changes this week, with one big clump in
  mv88e6xxx. Nothing of note, really.

  Current release - regressions:

   - smc: keep smc_close_final()'s error code during active close

  Current release - new code bugs:

   - iwlwifi: various static checker fixes (int overflow, leaks, missing
     error codes)

   - rtw89: fix size of firmware header before transfer, avoid crash

   - mt76: fix timestamp check in tx_status; fix pktid leak;

   - mscc: ocelot: fix missing unlock on error in ocelot_hwstamp_set()

  Previous releases - regressions:

   - smc: fix list corruption in smc_lgr_cleanup_early

   - ipv4: convert fib_num_tclassid_users to atomic_t

  Previous releases - always broken:

   - tls: fix authentication failure in CCM mode

   - vrf: reset IPCB/IP6CB when processing outbound pkts, prevent
     incorrect processing

   - dsa: mv88e6xxx: fixes for various device errata

   - rds: correct socket tunable error in rds_tcp_tune()

   - ipv6: fix memory leak in fib6_rule_suppress

   - wireguard: reset peer src endpoint when netns exits

   - wireguard: improve resilience to DoS around incoming handshakes

   - tcp: fix page frag corruption on page fault which involves TCP

   - mpls: fix missing attributes in delete notifications

   - mt7915: fix NULL pointer dereference with ad-hoc mode

  Misc:

   - rt2x00: be more lenient about EPROTO errors during start

   - mlx4_en: update reported link modes for 1/10G"

* tag 'net-5.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (85 commits)
  net: dsa: b53: Add SPI ID table
  gro: Fix inconsistent indenting
  selftests: net: Correct case name
  net/rds: correct socket tunable error in rds_tcp_tune()
  mctp: Don't let RTM_DELROUTE delete local routes
  net/smc: Keep smc_close_final rc during active close
  ibmvnic: drop bad optimization in reuse_tx_pools()
  ibmvnic: drop bad optimization in reuse_rx_pools()
  net/smc: fix wrong list_del in smc_lgr_cleanup_early
  Fix Comment of ETH_P_802_3_MIN
  ethernet: aquantia: Try MAC address from device tree
  ipv4: convert fib_num_tclassid_users to atomic_t
  net: avoid uninit-value from tcp_conn_request
  net: annotate data-races on txq->xmit_lock_owner
  octeontx2-af: Fix a memleak bug in rvu_mbox_init()
  net/mlx4_en: Fix an use-after-free bug in mlx4_en_try_alloc_resources()
  vrf: Reset IPCB/IP6CB when processing outbound pkts in vrf dev xmit
  net: qlogic: qlcnic: Fix a NULL pointer dereference in qlcnic_83xx_add_rings()
  net: dsa: mv88e6xxx: Link in pcs_get_state() if AN is bypassed
  net: dsa: mv88e6xxx: Fix inband AN for 2500base-x on 88E6393X family
  ...

2 years agoMerge tag 'trace-v5.16-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt...
Linus Torvalds [Thu, 2 Dec 2021 19:07:41 +0000 (11:07 -0800)]
Merge tag 'trace-v5.16-rc3' of git://git./linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "Three tracing fixes:

   - Allow compares of strings when using signed and unsigned characters

   - Fix kmemleak false positive for histogram entries

   - Handle negative numbers for user defined kretprobe data sizes"

* tag 'trace-v5.16-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  kprobes: Limit max data_size of the kretprobe instances
  tracing: Fix a kmemleak false positive in tracing_map
  tracing/histograms: String compares should not care about signed values

2 years agoMerge tag 'for-linus-5.16-2' of git://github.com/cminyard/linux-ipmi
Linus Torvalds [Thu, 2 Dec 2021 18:56:16 +0000 (10:56 -0800)]
Merge tag 'for-linus-5.16-2' of git://github.com/cminyard/linux-ipmi

Pull IPMI fixes from Corey Minyard:
 "Some changes that went in 5.16 had issues. When working on the design
  a piece was redesigned and things got missed. And the message type was
  not being initialized when it was allocated, resulting in crashes.

  In addition, the IPMI driver has had a shutdown issue where it could
  still have an item in a system workqueue after it had been shutdown.
  Move to a private workqueue to avoid that problem"

* tag 'for-linus-5.16-2' of git://github.com/cminyard/linux-ipmi:
  ipmi:ipmb: Fix unknown command response
  ipmi: fix IPMI_SMI_MSG_TYPE_IPMB_DIRECT response length checking
  ipmi: fix oob access due to uninit smi_msg type
  ipmi: msghandler: Make symbol 'remove_work_wq' static
  ipmi: Move remove_work to dedicated workqueue

2 years agos390: update defconfigs
Heiko Carstens [Fri, 26 Nov 2021 14:16:31 +0000 (15:16 +0100)]
s390: update defconfigs

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2 years agoRevert "drm/i915: Implement Wa_1508744258"
José Roberto de Souza [Fri, 19 Nov 2021 14:09:30 +0000 (06:09 -0800)]
Revert "drm/i915: Implement Wa_1508744258"

This workarounds are causing hangs, because I missed the fact that it
needs to be enabled for all cases and disabled when doing a resolve
pass.

So KMD only needs to whitelist it and UMD will be the one setting it
on per case.

This reverts commit 28ec02c9cbebf3feeaf21a59df9dfbc02bda3362.

Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/4145
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Fixes: 28ec02c9cbeb ("drm/i915: Implement Wa_1508744258")
Reviewed-by: Matt Atwood <matthew.s.atwood@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211119140931.32791-1-jose.souza@intel.com
(cherry picked from commit f3799ff16fcfacd44aee55db162830df461b631f)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
2 years agosched/cputime: Fix getrusage(RUSAGE_THREAD) with nohz_full
Frederic Weisbecker [Tue, 26 Oct 2021 14:10:55 +0000 (16:10 +0200)]
sched/cputime: Fix getrusage(RUSAGE_THREAD) with nohz_full

getrusage(RUSAGE_THREAD) with nohz_full may return shorter utime/stime
than the actual time.

task_cputime_adjusted() snapshots utime and stime and then adjust their
sum to match the scheduler maintained cputime.sum_exec_runtime.
Unfortunately in nohz_full, sum_exec_runtime is only updated once per
second in the worst case, causing a discrepancy against utime and stime
that can be updated anytime by the reader using vtime.

To fix this situation, perform an update of cputime.sum_exec_runtime
when the cputime snapshot reports the task as actually running while
the tick is disabled. The related overhead is then contained within the
relevant situations.

Reported-by: Hasegawa Hitomi <hasegawa-hitomi@fujitsu.com>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Hasegawa Hitomi <hasegawa-hitomi@fujitsu.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Acked-by: Phil Auld <pauld@redhat.com>
Link: https://lore.kernel.org/r/20211026141055.57358-3-frederic@kernel.org
2 years agotimers/nohz: Last resort update jiffies on nohz_full IRQ entry
Frederic Weisbecker [Tue, 26 Oct 2021 14:10:54 +0000 (16:10 +0200)]
timers/nohz: Last resort update jiffies on nohz_full IRQ entry

When at least one CPU runs in nohz_full mode, a dedicated timekeeper CPU
is guaranteed to stay online and to never stop its tick.

Meanwhile on some rare case, the dedicated timekeeper may be running
with interrupts disabled for a while, such as in stop_machine.

If jiffies stop being updated, a nohz_full CPU may end up endlessly
programming the next tick in the past, taking the last jiffies update
monotonic timestamp as a stale base, resulting in an tick storm.

Here is a scenario where it matters:

0) CPU 0 is the timekeeper and CPU 1 a nohz_full CPU.

1) A stop machine callback is queued to execute somewhere.

2) CPU 0 reaches MULTI_STOP_DISABLE_IRQ while CPU 1 is still in
   MULTI_STOP_PREPARE. Hence CPU 0 can't do its timekeeping duty. CPU 1
   can still take IRQs.

3) CPU 1 receives an IRQ which queues a timer callback one jiffy forward.

4) On IRQ exit, CPU 1 schedules the tick one jiffy forward, taking
   last_jiffies_update as a base. But last_jiffies_update hasn't been
   updated for 2 jiffies since the timekeeper has interrupts disabled.

5) clockevents_program_event(), which relies on ktime_get(), observes
   that the expiration is in the past and therefore programs the min
   delta event on the clock.

6) The tick fires immediately, goto 3)

7) Tick storm, the nohz_full CPU is drown and takes ages to reach
   MULTI_STOP_DISABLE_IRQ, which is the only way out of this situation.

Solve this with unconditionally updating jiffies if the value is stale
on nohz_full IRQ entry. IRQs and other disturbances are expected to be
rare enough on nohz_full for the unconditional call to ktime_get() to
actually matter.

Reported-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/20211026141055.57358-2-frederic@kernel.org
2 years agonet: dsa: b53: Add SPI ID table
Florian Fainelli [Thu, 2 Dec 2021 04:17:20 +0000 (20:17 -0800)]
net: dsa: b53: Add SPI ID table

Currently autoloading for SPI devices does not use the DT ID table, it
uses SPI modalises. Supporting OF modalises is going to be difficult if
not impractical, an attempt was made but has been reverted, so ensure
that module autoloading works for this driver by adding an id_table
listing the SPI IDs for everything.

Fixes: 96c8395e2166 ("spi: Revert modalias changes")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2 years agogro: Fix inconsistent indenting
Jiapeng Chong [Thu, 2 Dec 2021 08:30:42 +0000 (16:30 +0800)]
gro: Fix inconsistent indenting

Eliminate the follow smatch warning:

net/ipv6/ip6_offload.c:249 ipv6_gro_receive() warn: inconsistent
indenting.

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>