platform/kernel/linux-stable.git
11 years agopowerpc/eeh: EEH backend for P7IOC
Gavin Shan [Thu, 20 Jun 2013 05:21:06 +0000 (13:21 +0800)]
powerpc/eeh: EEH backend for P7IOC

For EEH on PowerNV platform, the overall architecture is different
from that on pSeries platform. In order to support multiple I/O chips
in future, we split EEH to 3 layers for PowerNV platform: EEH core,
platform layer, I/O layer. It would give EEH implementation on PowerNV
platform much more flexibility in future.

The patch adds the EEH backend for P7IOC.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/eeh: Sync OPAL API with firmware
Gavin Shan [Thu, 20 Jun 2013 05:21:05 +0000 (13:21 +0800)]
powerpc/eeh: Sync OPAL API with firmware

The patch synchronizes OPAL APIs between kernel and firmware. Also,
we starts to replace opal_pci_get_phb_diag_data() with the similar
opal_pci_get_phb_diag_data2() and the former OPAL API would return
OPAL_UNSUPPORTED from now on.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/eeh: EEH core to handle special event
Gavin Shan [Thu, 20 Jun 2013 05:21:04 +0000 (13:21 +0800)]
powerpc/eeh: EEH core to handle special event

On PowerNV platform, the EEH event caused by interrupt won't have
binding PE. The patch enables EEH core to handle the special event.
To avoid the current logic we have, The eeh_handle_event() is renamed
to eeh_handle_normal_event(), and the eeh_handle_special_event() is
introduced. The function eeh_handle_event() dispatches to above two
functions according to the input parameter. Besides, new backend
"next_error" added to eeh_ops and it's expected to have following
return values:

        4 - Dead IOC           3 - Dead PHB
        2 - Fenced PHB         1 - Frozen PE
        0 - No error found

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/eeh: Export confirm_error_lock
Gavin Shan [Thu, 20 Jun 2013 05:21:03 +0000 (13:21 +0800)]
powerpc/eeh: Export confirm_error_lock

An EEH event is created and queued to the event queue for each
ingress EEH error. When there're mutiple EEH errors, we need serialize
the process to keep consistent PE state (flags). The spinlock
"confirm_error_lock" was introduced for the purpose. We'll inject
EEH event upon error reporting interrupts on PowerNV platform. So
we export the spinlock for that to use for consistent PE state.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/eeh: Allow to purge EEH events
Gavin Shan [Thu, 20 Jun 2013 05:21:02 +0000 (13:21 +0800)]
powerpc/eeh: Allow to purge EEH events

On PowerNV platform, we might run into the situation where subsequent
events are duplicated events of former one, which is being processed.
For the case, we need the function implemented by the patch to purge
EEH events accordingly.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/eeh: Trace time on first error for PE
Gavin Shan [Thu, 20 Jun 2013 05:21:01 +0000 (13:21 +0800)]
powerpc/eeh: Trace time on first error for PE

We're not expecting that one specific PE got frozen for over 5
times in last hour. Otherwise, the PE will be removed from the
system upon newly coming EEH errors. The patch introduces time
stamp to trace the first error on specific PE in last hour and
function to update that accordingly. Besides, the time stamp
is recovered during PE hotplug path as we did for frozen count.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/eeh: Single kthread to handle events
Gavin Shan [Thu, 20 Jun 2013 05:21:00 +0000 (13:21 +0800)]
powerpc/eeh: Single kthread to handle events

We possiblly have multiple kthreads running for multiple EEH errors
(events) and use one spinlock to make the process of handling those
EEH events serialized. That's unnecessary and the patch creates only
one kthread, which is started during EEH core initialization time in
eeh_init(). A new semaphore introduced to count the number of existing
EEH events in the queue and the kthread waiting on the semaphore.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/eeh: Delay EEH probe during hotplug
Gavin Shan [Thu, 20 Jun 2013 05:20:59 +0000 (13:20 +0800)]
powerpc/eeh: Delay EEH probe during hotplug

While doing EEH recovery, the PCI devices of the problematic PE
should be removed and then added to the system again. During the
so-called hotplug event, the PCI devices of the problematic PE
will be probed through early/late phase. We would delay EEH probe
on late point for PowerNV platform since the PCI device isn't
available in early phase.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/eeh: Refactor eeh_reset_pe_once()
Gavin Shan [Thu, 20 Jun 2013 05:20:58 +0000 (13:20 +0800)]
powerpc/eeh: Refactor eeh_reset_pe_once()

We shouldn't check that the returned PE status is exactly equal to
(EEH_STATE_MMIO_ACTIVE | EEH_STATE_DMA_ACTIVE) but instead only check
that they are both set.

[benh: changelog]
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/eeh: EEH post initialization operation
Gavin Shan [Thu, 20 Jun 2013 05:20:57 +0000 (13:20 +0800)]
powerpc/eeh: EEH post initialization operation

The patch adds new EEH operation post_init. It's used to notify
the platform that EEH core has completed the EEH probe. By that,
PowerNV platform starts to use the services supplied by EEH
functionality.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/eeh: Make eeh_init() public
Gavin Shan [Thu, 20 Jun 2013 05:20:56 +0000 (13:20 +0800)]
powerpc/eeh: Make eeh_init() public

For EEH on PowerNV platform, we will do EEH probe based on the
real PCI devices. The PCI devices are available after PCI probe.
So we have to call eeh_init() explicitly on PowerNV platform
after PCI probe. The patch also does EEH probe for PowerNV platform
in eeh_init().

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/eeh: Trace PCI bus from PE
Gavin Shan [Thu, 20 Jun 2013 05:20:55 +0000 (13:20 +0800)]
powerpc/eeh: Trace PCI bus from PE

There're several types of PEs can be supported for now: PHB, Bus
and Device dependent PE. For PCI bus dependent PE, tracing the
corresponding PCI bus from PE (struct eeh_pe) would make the code
more efficient. The patch also enables the retrieval of PCI bus based
on the PCI bus dependent PE.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/eeh: Make eeh_pe_get() public
Gavin Shan [Thu, 20 Jun 2013 05:20:54 +0000 (13:20 +0800)]
powerpc/eeh: Make eeh_pe_get() public

While processing EEH event interrupt from P7IOC, we need function
to retrieve the PE according to the indicated EEH device. The patch
makes function eeh_pe_get() public so that other source files can call
it for that purpose. Also, the patch fixes referring to wrong BDF
(Bus/Device/Function) address while searching PE in function
__eeh_pe_get().

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/eeh: Make eeh_phb_pe_get() public
Gavin Shan [Thu, 20 Jun 2013 05:20:53 +0000 (13:20 +0800)]
powerpc/eeh: Make eeh_phb_pe_get() public

One of the possible cases indicated by P7IOC interrupt is fenced
PHB. For that case, we need fetch the PE corresponding to the PHB
and disable the PHB and all subordinate PCI buses/devices, recover
from the fenced state and eventually enable the whole PHB. We need
one function to fetch the PHB PE outside eeh_pe.c and the patch is
going to make eeh_phb_pe_get() public for that purpose.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/eeh: Move common part to kernel directory
Gavin Shan [Thu, 20 Jun 2013 05:20:52 +0000 (13:20 +0800)]
powerpc/eeh: Move common part to kernel directory

The patch moves the common part of EEH core into arch/powerpc/kernel
directory so that we needn't PPC_PSERIES while compiling POWERNV
platform:

        * Move the EEH common part into arch/powerpc/kernel
        * Move the functions for PCI hotplug from pSeries platform to
          arch/powerpc/kernel/pci-hotplug.c
        * Move CONFIG_EEH from arch/powerpc/platforms/pseries/Kconfig to
          arch/powerpc/platforms/Kconfig
        * Adjust makefile accordingly

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/eeh: Cleanup for EEH core
Gavin Shan [Thu, 20 Jun 2013 05:20:51 +0000 (13:20 +0800)]
powerpc/eeh: Cleanup for EEH core

Cleanup on EEH core to remove unnecessary whitespaces.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/tm: Fix return of active 64bit signals
Michael Neuling [Sun, 9 Jun 2013 11:23:19 +0000 (21:23 +1000)]
powerpc/tm: Fix return of active 64bit signals

Currently we only restore signals which are transactionally suspended but it's
possible that the transaction can be restored even when it's active.  Most
likely this will result in a transactional rollback by the hardware as the
transaction will have been doomed by an earlier treclaim.

The current code is a legacy of earlier kernel implementations which did
software rollback of active transactions in the kernel.  That code has now gone
but we didn't correctly fix up this part of the signals code which still makes
assumptions based on having software rollback.

This changes the signal return code to always restore both contexts on 64 bit
signal return.  It also ensures that the MSR TM bits are properly restored from
the signal context which they are not currently.

Signed-off-by: Michael Neuling <mikey@neuling.org>
cc: stable@vger.kernel.org (v3.9+)
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/tm: Fix return of 32bit rt signals to active transactions
Michael Neuling [Sun, 9 Jun 2013 11:23:18 +0000 (21:23 +1000)]
powerpc/tm: Fix return of 32bit rt signals to active transactions

Currently we only restore signals which are transactionally suspended but it's
possible that the transaction can be restored even when it's active.  Most
likely this will result in a transactional rollback by the hardware as the
transaction will have been doomed by an earlier treclaim.

The current code is a legacy of earlier kernel implementations which did
software rollback of active transactions in the kernel.  That code has now gone
but we didn't correctly fix up this part of the signals code which still makes
assumptions based on having software rollback.

This changes the signal return code to always restore both contexts on 32 bit
rt signal return.

Signed-off-by: Michael Neuling <mikey@neuling.org>
cc: stable@vger.kernel.org (v3.9+)
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/tm: Fix restoration of MSR on 32bit signal return
Michael Neuling [Sun, 9 Jun 2013 11:23:17 +0000 (21:23 +1000)]
powerpc/tm: Fix restoration of MSR on 32bit signal return

Currently we clear out the MSR TM bits on signal return assuming that the
signal should never return to an active transaction.

This is bogus as the user may do this.  It's most likely the transaction will
be doomed due to a treclaim but that's a problem for the HW not the kernel.

The current code is a legacy of earlier kernel implementations which did
software rollback of active transactions in the kernel.  That code has now gone
but we didn't correctly fix up this part of the signals code which still makes
the assumption that it must be returning to a suspended transaction.

This pulls out both MSR TM bits from the user supplied context rather than just
setting TM suspend.  We pull out only the bits needed to ensure the user can't
do anything dangerous to the MSR.

Signed-off-by: Michael Neuling <mikey@neuling.org>
cc: stable@vger.kernel.org (v3.9+)
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/tm: Fix 32 bit non-rt signals
Michael Neuling [Sun, 9 Jun 2013 11:23:16 +0000 (21:23 +1000)]
powerpc/tm: Fix 32 bit non-rt signals

Currently sys_sigreturn() is TM unaware.  Therefore, if we take a 32 bit signal
without SIGINFO (non RT) inside a transaction, on signal return we don't
restore the signal frame correctly.

This checks if the signal frame being restoring is an active transaction, and
if so, it copies the additional state to ptregs so it can be restored.

Signed-off-by: Michael Neuling <mikey@neuling.org>
cc: stable@vger.kernel.org (v3.9+)
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/tm: Fix writing top half of MSR on 32 bit signals
Michael Neuling [Sun, 9 Jun 2013 11:23:15 +0000 (21:23 +1000)]
powerpc/tm: Fix writing top half of MSR on 32 bit signals

The MSR TM controls are in the top 32 bits of the MSR hence on 32 bit signals,
we stick the top half of the MSR in the checkpointed signal context so that the
user can access it.

Unfortunately, we don't currently write anything to the checkpointed signal
context when coming in a from a non transactional process and hence the top MSR
bits can contain junk.

This updates the 32 bit signal handling code to always write something to the
top MSR bits so that users know if the process is transactional or not and the
kernel can use it on signal return.

Signed-off-by: Michael Neuling <mikey@neuling.org>
cc: stable@vger.kernel.org (v3.9+)
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/8xx: Remove 8xx specific "minimal FPU emulation"
Benjamin Herrenschmidt [Sun, 9 Jun 2013 07:04:58 +0000 (17:04 +1000)]
powerpc/8xx: Remove 8xx specific "minimal FPU emulation"

This is duplicated code from math-emu and implements such a small
subset of the FPU (load/stores/fmr) that it's essentially pointless
nowdays.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/math-emu: Allow math-emu to be used for HW FPU
Benjamin Herrenschmidt [Sun, 9 Jun 2013 07:01:24 +0000 (17:01 +1000)]
powerpc/math-emu: Allow math-emu to be used for HW FPU

(Including 64-bit ones)

This allow SW emulation by the kernel of optional instructions
such as fsqrt which aren't implemented on some processors, and
thus fixes some Fedora 19 issues such as Anaconda since the
compiler is set to generate those by default on 64-bit.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/math-emu: Fix decoding of some instructions
Benjamin Herrenschmidt [Sun, 9 Jun 2013 07:00:42 +0000 (17:00 +1000)]
powerpc/math-emu: Fix decoding of some instructions

The decoding of some instructions such as fsqrt{s} was incorrect,
using the wrong registers, and thus could not work.

This fixes it and also adds a couple of place holders for missing
instructions.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/pseries: Read common partition via pstore
Aruna Balakrishnaiah [Wed, 5 Jun 2013 18:52:20 +0000 (00:22 +0530)]
powerpc/pseries: Read common partition via pstore

This patch exploits pstore subsystem to read details of common partition
in NVRAM to a separate file in /dev/pstore. For instance, common partition
details will be stored in a file named [common-nvram-6].

Signed-off-by: Aruna Balakrishnaiah <aruna@linux.vnet.ibm.com>
Reviewed-by: Jim Keniston <jkenisto@us.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/pseries: Read of-config partition via pstore
Aruna Balakrishnaiah [Wed, 5 Jun 2013 18:52:10 +0000 (00:22 +0530)]
powerpc/pseries: Read of-config partition via pstore

This patch set exploits the pstore subsystem to read details of
of-config partition in NVRAM to a separate file in /dev/pstore.
For instance, of-config partition details will be stored in a
file named [of-nvram-5].

Signed-off-by: Aruna Balakrishnaiah <aruna@linux.vnet.ibm.com>
Reviewed-by: Jim Keniston <jkenisto@us.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/pseries: Distinguish between a os-partition and non-os partition
Aruna Balakrishnaiah [Wed, 5 Jun 2013 18:51:59 +0000 (00:21 +0530)]
powerpc/pseries: Distinguish between a os-partition and non-os partition

Introduce os_partition member in nvram_os_partition structure to identify
if the partition is an os partition or not. This will be useful to handle
non-os partitions of-config and common.

Signed-off-by: Aruna Balakrishnaiah <aruna@linux.vnet.ibm.com>
Reviewed-by: Jim Keniston <jkenisto@us.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/pseries: Read rtas partition via pstore
Aruna Balakrishnaiah [Wed, 5 Jun 2013 18:51:44 +0000 (00:21 +0530)]
powerpc/pseries: Read rtas partition via pstore

This patch set exploits the pstore subsystem to read details of rtas partition
in NVRAM to a separate file in /dev/pstore. For instance, rtas details will be
stored in a file named [rtas-nvram-4].

Signed-off-by: Aruna Balakrishnaiah <aruna@linux.vnet.ibm.com>
Reviewed-by: Jim Keniston <jkenisto@us.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/pseries: Read/Write oops nvram partition via pstore
Aruna Balakrishnaiah [Wed, 5 Jun 2013 18:51:32 +0000 (00:21 +0530)]
powerpc/pseries: Read/Write oops nvram partition via pstore

IBM's p series machines provide persistent storage for LPARs through NVRAM.
NVRAM's lnx,oops-log partition is used to log oops messages.
Currently the kernel provides the contents of p-series NVRAM only as a
simple stream of bytes via /dev/nvram, which must be interpreted in user
space by the nvram command in the powerpc-utils package.

This patch set exploits the pstore subsystem to expose oops partition in
NVRAM as a separate file in /dev/pstore. For instance, Oops messages will be
stored in a file named [dmesg-nvram-2]. In case pstore registration fails it
will fall back to kmsg_dump mechanism.

This patch will read/write the oops messages from/to this partition via pstore.

Signed-off-by: Jim Keniston <jkenisto@us.ibm.com>
Signed-off-by: Aruna Balakrishnaiah <aruna@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/pseries: Introduce generic read function to read nvram-partitions
Aruna Balakrishnaiah [Wed, 5 Jun 2013 18:51:16 +0000 (00:21 +0530)]
powerpc/pseries: Introduce generic read function to read nvram-partitions

Introduce generic read function to read nvram partitions other than rtas.
nvram_read_error_log will be retained which is used to read rtas partition
from rtasd. nvram_read_partition is the generic read function to read from
any nvram partition.

Signed-off-by: Aruna Balakrishnaiah <aruna@linux.vnet.ibm.com>
Reviewed-by: Jim Keniston <jkenisto@us.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/pseries: Add version and timestamp to oops header
Aruna Balakrishnaiah [Wed, 5 Jun 2013 18:51:05 +0000 (00:21 +0530)]
powerpc/pseries: Add version and timestamp to oops header

Introduce version and timestamp information in the oops header.
oops_log_info (oops header) holds version (to distinguish between old
and new format oops header), length of the oops text
(compressed or uncompressed) and timestamp.

The version field will sit in the same place as the length in old
headers. version is assigned 5000 (greater than oops partition size)
so that existing tools will refuse to dump new style partitions as
the length is too large. The updated tools will work with both
old and new format headers.

Signed-off-by: Aruna Balakrishnaiah <aruna@linux.vnet.ibm.com>
Reviewed-by: Jim Keniston <jkenisto@us.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/pseries: Remove syslog prefix in uncompressed oops text
Aruna Balakrishnaiah [Wed, 5 Jun 2013 18:50:55 +0000 (00:20 +0530)]
powerpc/pseries: Remove syslog prefix in uncompressed oops text

Removal of syslog prefix in the uncompressed oops text will
help in capturing more oops data.

Signed-off-by: Aruna Balakrishnaiah <aruna@linux.vnet.ibm.com>
Reviewed-by: Jim Keniston <jkenisto@us.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/eeh: Enhance converting EEH dev
Gavin Shan [Wed, 5 Jun 2013 07:34:03 +0000 (15:34 +0800)]
powerpc/eeh: Enhance converting EEH dev

Under some special circumstances, the EEH device doesn't have the
associated device tree node or PCI device. The patch enhances those
functions converting EEH device to device tree node or PCI device
accordingly to avoid unnecessary system crash.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/eeh: Fix fetching bus for single-dev-PE
Gavin Shan [Wed, 5 Jun 2013 07:34:02 +0000 (15:34 +0800)]
powerpc/eeh: Fix fetching bus for single-dev-PE

While running Linux as guest on top of phyp, we possiblly have
PE that includes single PCI device. However, we didn't return
its PCI bus correctly and it leads to failure on recovery from
EEH errors for single-dev-PE. The patch fixes the issue.

Cc: <stable@vger.kernel.org> # v3.7+
Cc: Steve Best <sbest@us.ibm.com>
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc: Align thread->fpr to 16 bytes
Anton Blanchard [Wed, 5 Jun 2013 03:02:26 +0000 (13:02 +1000)]
powerpc: Align thread->fpr to 16 bytes

On newer CPUs we use VSX loads and stores to the thread->fpr array.
For best performance we need to ensure 16 byte alignment.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/pseries: Use 'true' instead of '1' for orderly_poweroff
liguang [Thu, 30 May 2013 07:20:33 +0000 (15:20 +0800)]
powerpc/pseries: Use 'true' instead of '1' for orderly_poweroff

orderly_poweroff is expecting a bool parameter, so
use 'true' instead '1'

Signed-off-by: liguang <lig.fnst@cn.fujitsu.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/smp: Use '==' instead of '<' for system_state
liguang [Thu, 30 May 2013 06:47:53 +0000 (14:47 +0800)]
powerpc/smp: Use '==' instead of '<' for system_state

'system_state < SYSTEM_RUNNING' will have same effect
with 'system_state == SYSTEM_BOOTING', but the later
one is more clearer.

Signed-off-by: liguang <lig.fnst@cn.fujitsu.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc: Restore dbcr0 on user space exit
Bharat Bhushan [Wed, 22 May 2013 04:20:59 +0000 (09:50 +0530)]
powerpc: Restore dbcr0 on user space exit

On BookE (Branch taken + Single Step) is as same as Branch Taken
on BookS and in Linux we simulate BookS behavior for BookE as well.
When doing so, in Branch taken handling we want to set DBCR0_IC but
we update the current->thread->dbcr0 and not DBCR0.

Now on 64bit the current->thread.dbcr0 (and other debug registers)
is synchronized ONLY on context switch flow. But after handling
Branch taken in debug exception if we return back to user space
without context switch then single stepping change (DBCR0_ICMP)
does not get written in h/w DBCR0 and Instruction Complete exception
does not happen.

This fixes using ptrace reliably on BookE-PowerPC

lmbench latency test (lat_syscall) Results are (they varies a little
on each run)

1) ./lat_syscall <action> /dev/shm/uImage

action: Open read write stat fstat null
Before: 3.8618 0.2017 0.2851 1.6789 0.2256 0.0856
After: 3.8580 0.2017 0.2851 1.6955 0.2255 0.0856

1) ./lat_syscall -P 2 -N 10 <action> /dev/shm/uImage
action: Open read write stat fstat null
Before: 4.1388 0.2238 0.3066 1.7106 0.2256 0.0856
After: 4.1413 0.2236 0.3062 1.7107 0.2256 0.0856

[ Slightly modified to avoid extra branch in the fast path
  on Book3S and fix build on all non-BookE 64-bit -- BenH
]

Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc: Debug control and status registers are 32bit
Bharat Bhushan [Wed, 22 May 2013 04:20:58 +0000 (09:50 +0530)]
powerpc: Debug control and status registers are 32bit

Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/vfio: Enable on pSeries platform
Alexey Kardashevskiy [Tue, 21 May 2013 03:33:11 +0000 (13:33 +1000)]
powerpc/vfio: Enable on pSeries platform

The enables VFIO on the pSeries platform, enabling user space
programs to access PCI devices directly.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/vfio: Implement IOMMU driver for VFIO
Alexey Kardashevskiy [Tue, 21 May 2013 03:33:10 +0000 (13:33 +1000)]
powerpc/vfio: Implement IOMMU driver for VFIO

VFIO implements platform independent stuff such as
a PCI driver, BAR access (via read/write on a file descriptor
or direct mapping when possible) and IRQ signaling.

The platform dependent part includes IOMMU initialization
and handling.  This implements an IOMMU driver for VFIO
which does mapping/unmapping pages for the guest IO and
provides information about DMA window (required by a POWER
guest).

Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/vfio: Enable on PowerNV platform
Alexey Kardashevskiy [Tue, 21 May 2013 03:33:09 +0000 (13:33 +1000)]
powerpc/vfio: Enable on PowerNV platform

This initializes IOMMU groups based on the IOMMU configuration
discovered during the PCI scan on POWERNV (POWER non virtualized)
platform.  The IOMMU groups are to be used later by the VFIO driver,
which is used for PCI pass through.

It also implements an API for mapping/unmapping pages for
guest PCI drivers and providing DMA window properties.
This API is going to be used later by QEMU-VFIO to handle
h_put_tce hypercalls from the KVM guest.

The iommu_put_tce_user_mode() does only a single page mapping
as an API for adding many mappings at once is going to be
added later.

Although this driver has been tested only on the POWERNV
platform, it should work on any platform which supports
TCE tables.  As h_put_tce hypercall is received by the host
kernel and processed by the QEMU (what involves calling
the host kernel again), performance is not the best -
circa 220MB/s on 10Gb ethernet network.

To enable VFIO on POWER, enable SPAPR_TCE_IOMMU config
option and configure VFIO as required.

Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc: Update currituck pci/usb fixup for new board revision
Alistair Popple [Thu, 9 May 2013 00:42:13 +0000 (10:42 +1000)]
powerpc: Update currituck pci/usb fixup for new board revision

The currituck board uses a different IRQ for the pci usb host
controller depending on the board revision. This patch adds support
for newer board revisions by retrieving the board revision from the
FPGA and mapping the appropriate IRQ.

Signed-off-by: Alistair Popple <alistair@popple.id.au>
Acked-by: Tony Breeds <tony@bakeyournoodle.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc: Fix single step emulation of 32bit overflowed branches
Michael Neuling [Mon, 6 May 2013 11:32:40 +0000 (21:32 +1000)]
powerpc: Fix single step emulation of 32bit overflowed branches

Check truncate_if_32bit() on final write to nip.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc: Update default configurations
Alistair Popple [Mon, 29 Apr 2013 03:42:44 +0000 (13:42 +1000)]
powerpc: Update default configurations

Update default configurations for systems with CONFIG_BOOTX_TEXT
selected so that they continue to print early debug messages as is
currently the case.

Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc: Add a configuration option for early BootX/OpenFirmware debug
Alistair Popple [Mon, 29 Apr 2013 03:42:43 +0000 (13:42 +1000)]
powerpc: Add a configuration option for early BootX/OpenFirmware debug

Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/prom: Scan reserved-ranges node for memory reservations
Jeremy Kerr [Wed, 24 Apr 2013 06:26:30 +0000 (14:26 +0800)]
powerpc/prom: Scan reserved-ranges node for memory reservations

Based on benh's proposal at
https://lists.ozlabs.org/pipermail/linuxppc-dev/2012-September/101237.html,
this change provides support for reserving memory from the
reserved-ranges node at the root of the device tree.

We just call memblock_reserve on these ranges for now.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/mm: Make mmap_64.c compile on 32bit powerpc
Daniel Walker [Wed, 24 Apr 2013 00:50:33 +0000 (17:50 -0700)]
powerpc/mm: Make mmap_64.c compile on 32bit powerpc

There appears to be no good reason to keep this as 64bit only. It works
on 32bit also, and has checks so that it can work correctly with 32bit
binaries on 64bit hardware which is why I think this works.

I tested this on qemu using the virtex-ml507 machine type.

Before,

/bin2 # ./test & cat /proc/${!}/maps
00100000-00103000 r-xp 00000000 00:00 0          [vdso]
10000000-10007000 r-xp 00000000 00:01 454        /bin2/test
10017000-10018000 rw-p 00007000 00:01 454        /bin2/test
48000000-48020000 r-xp 00000000 00:01 224        /lib/ld-2.11.3.so
48021000-48023000 rw-p 00021000 00:01 224        /lib/ld-2.11.3.so
bfd03000-bfd24000 rw-p 00000000 00:00 0          [stack]
/bin2 # ./test & cat /proc/${!}/maps
00100000-00103000 r-xp 00000000 00:00 0          [vdso]
0fe6e000-0ffd8000 r-xp 00000000 00:01 214        /lib/libc-2.11.3.so
0ffd8000-0ffe8000 ---p 0016a000 00:01 214        /lib/libc-2.11.3.so
0ffe8000-0ffed000 rw-p 0016a000 00:01 214        /lib/libc-2.11.3.so
0ffed000-0fff0000 rw-p 00000000 00:00 0
10000000-10007000 r-xp 00000000 00:01 454        /bin2/test
10017000-10018000 rw-p 00007000 00:01 454        /bin2/test
48000000-48020000 r-xp 00000000 00:01 224        /lib/ld-2.11.3.so
48020000-48021000 rw-p 00000000 00:00 0
48021000-48023000 rw-p 00021000 00:01 224        /lib/ld-2.11.3.so
bf98a000-bf9ab000 rw-p 00000000 00:00 0          [stack]
/bin2 # ./test & cat /proc/${!}/maps
00100000-00103000 r-xp 00000000 00:00 0          [vdso]
0fe6e000-0ffd8000 r-xp 00000000 00:01 214        /lib/libc-2.11.3.so
0ffd8000-0ffe8000 ---p 0016a000 00:01 214        /lib/libc-2.11.3.so
0ffe8000-0ffed000 rw-p 0016a000 00:01 214        /lib/libc-2.11.3.so
0ffed000-0fff0000 rw-p 00000000 00:00 0
10000000-10007000 r-xp 00000000 00:01 454        /bin2/test
10017000-10018000 rw-p 00007000 00:01 454        /bin2/test
48000000-48020000 r-xp 00000000 00:01 224        /lib/ld-2.11.3.so
48020000-48021000 rw-p 00000000 00:00 0
48021000-48023000 rw-p 00021000 00:01 224        /lib/ld-2.11.3.so
bfa54000-bfa75000 rw-p 00000000 00:00 0          [stack]

After,

bash-4.1# ./test & cat /proc/${!}/maps
[7] 803
00100000-00103000 r-xp 00000000 00:00 0          [vdso]
10000000-10007000 r-xp 00000000 00:01 454        /bin2/test
10017000-10018000 rw-p 00007000 00:01 454        /bin2/test
b7eb0000-b7ed0000 r-xp 00000000 00:01 224        /lib/ld-2.11.3.so
b7ed1000-b7ed3000 rw-p 00021000 00:01 224        /lib/ld-2.11.3.so
bfbc0000-bfbe1000 rw-p 00000000 00:00 0          [stack]
bash-4.1# ./test & cat /proc/${!}/maps
[8] 805
00100000-00103000 r-xp 00000000 00:00 0          [vdso]
10000000-10007000 r-xp 00000000 00:01 454        /bin2/test
10017000-10018000 rw-p 00007000 00:01 454        /bin2/test
b7b03000-b7b23000 r-xp 00000000 00:01 224        /lib/ld-2.11.3.so
b7b24000-b7b26000 rw-p 00021000 00:01 224        /lib/ld-2.11.3.so
bfc27000-bfc48000 rw-p 00000000 00:00 0          [stack]
bash-4.1# ./test & cat /proc/${!}/maps
[9] 807
00100000-00103000 r-xp 00000000 00:00 0          [vdso]
10000000-10007000 r-xp 00000000 00:01 454        /bin2/test
10017000-10018000 rw-p 00007000 00:01 454        /bin2/test
b7f37000-b7f57000 r-xp 00000000 00:01 224        /lib/ld-2.11.3.so
b7f58000-b7f5a000 rw-p 00021000 00:01 224        /lib/ld-2.11.3.so
bff96000-bffb7000 rw-p 00000000 00:00 0          [stack]

Signed-off-by: Daniel Walker <dwalker@fifo90.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc: Remove the unneeded trigger of decrementer interrupt in decrementer_check_ov...
Kevin Hao [Wed, 17 Apr 2013 09:50:35 +0000 (17:50 +0800)]
powerpc: Remove the unneeded trigger of decrementer interrupt in decrementer_check_overflow

Previously in order to handle the edge sensitive decrementers,
we choose to set the decrementer to 1 to trigger a decrementer
interrupt when re-enabling interrupts. But with the rework of the
lazy EE, we would replay the decrementer interrupt when re-enabling
interrupts if a decrementer interrupt occurs with irq soft-disabled.
So there is no need to trigger a decrementer interrupt in this case
any more.

Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/mm/nohash: Ignore NULL stale_map entries
Scott Wood [Thu, 21 Mar 2013 00:06:12 +0000 (19:06 -0500)]
powerpc/mm/nohash: Ignore NULL stale_map entries

This happens with threads that are offline due to CPU hotplug
(including threads that were never "plugged in" to begin with because
SMT is disabled).

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc: Move the single step enable code to a generic path
Suzuki K. Poulose [Mon, 3 Dec 2012 15:08:37 +0000 (20:38 +0530)]
powerpc: Move the single step enable code to a generic path

This patch moves the single step enable code used by kprobe to a generic
routine header so that, it can be re-used by other code, in this case,
uprobes. No functional changes.

Signed-off-by: Suzuki K. Poulose <suzuki@in.ibm.com>
Cc: Ananth N Mavinakaynahalli <ananth@in.ibm.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: linuxppc-dev@ozlabs.org
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc/kprobes: Do not disable External interrupts during single step
Suzuki K. Poulose [Mon, 3 Dec 2012 15:07:42 +0000 (20:37 +0530)]
powerpc/kprobes: Do not disable External interrupts during single step

External/Decrement exceptions have lower priority than the Debug Exception.
So, we don't have to disable the External interrupts before a single step.
However, on BookE, Critical Input Exception(CE) has higher priority than a
Debug Exception. Hence we mask them.

Signed-off-by: Suzuki K. Poulose <suzuki@in.ibm.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Ananth N Mavinakaynahalli <ananth@in.ibm.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: linuxppc-dev@ozlabs.org
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agopowerpc: Mark low level irq handlers NO_THREAD
Thomas Gleixner [Wed, 13 Feb 2013 22:38:51 +0000 (23:38 +0100)]
powerpc: Mark low level irq handlers NO_THREAD

These low level handlers cannot be threaded. Mark them NO_THREAD

Reported-by: leroy christophe <christophe.leroy@c-s.fr>
Tested-by: leroy christophe <christophe.leroy@c-s.fr>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agomm/THP: deposit the transpare huge pgtable before set_pmd
Aneesh Kumar K.V [Thu, 6 Jun 2013 00:14:06 +0000 (17:14 -0700)]
mm/THP: deposit the transpare huge pgtable before set_pmd

Architectures like powerpc use the deposited pgtable to store hash index
values.  We need to make the deposted pgtable is visible to other cpus
before we are ready to take a hash fault.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agomm/THP: don't use HPAGE_SHIFT in transparent hugepage code
Aneesh Kumar K.V [Thu, 6 Jun 2013 00:14:05 +0000 (17:14 -0700)]
mm/THP: don't use HPAGE_SHIFT in transparent hugepage code

For architectures like powerpc that support multiple explicit hugepage
sizes, HPAGE_SHIFT indicate the default explicit hugepage shift.  For THP
to work the hugepage size should be same as PMD_SIZE.  So use PMD_SHIFT
directly.  So move the define outside CONFIG_TRANSPARENT_HUGEPAGE #ifdef
because we want to use these defines in generic code with if
(pmd_trans_huge()) conditional.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agomm/THP: withdraw the pgtable after pmdp related operations
Aneesh Kumar K.V [Thu, 6 Jun 2013 00:14:04 +0000 (17:14 -0700)]
mm/THP: withdraw the pgtable after pmdp related operations

For architectures like ppc64 we look at deposited pgtable when calling
pmdp_get_and_clear.  So do the pgtable_trans_huge_withdraw after finishing
pmdp related operations.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agomm/THP: add pmd args to pgtable deposit and withdraw APIs
Aneesh Kumar K.V [Thu, 6 Jun 2013 00:14:02 +0000 (17:14 -0700)]
mm/THP: add pmd args to pgtable deposit and withdraw APIs

This will be later used by powerpc THP support.  In powerpc we want to use
pgtable for storing the hash index values.  So instead of adding them to
mm_context list, we would like to store them in the second half of pmd

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agomm/thp: use the correct function when updating access flags
Aneesh Kumar K.V [Thu, 6 Jun 2013 07:20:34 +0000 (00:20 -0700)]
mm/thp: use the correct function when updating access flags

We should use pmdp_set_access_flags to update access flags.  Archs like
powerpc use extra checks(_PAGE_BUSY) when updating a hugepage PTE.  A
set_pmd_at doesn't do those checks.  We should use set_pmd_at only when
updating a none hugepage PTE.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>a
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
11 years agoMerge tag 'acpi-3.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael...
Linus Torvalds [Thu, 13 Jun 2013 20:09:50 +0000 (13:09 -0700)]
Merge tag 'acpi-3.10-rc6' of git://git./linux/kernel/git/rafael/linux-pm

Pull ACPI fix from Rafael Wysocki:
 "This is an alternative fix for the regression introduced in 3.9 whose
  previous fix had to be reverted right before 3.10-rc5, because it
  broke one of the Tony's machines.

  In this one the check is confined to the ACPI video driver (which is
  the only one causing the problem to happen in the first place) and the
  Tony's box shouldn't even notice it.

   - ACPI fix for an issue causing ACPI video driver to attempt to bind
     to devices it shouldn't touch from Rafael J Wysocki."

* tag 'acpi-3.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI / video: Do not bind to device objects with a scan handler

11 years agoMerge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Thu, 13 Jun 2013 20:08:51 +0000 (13:08 -0700)]
Merge branch 'x86-urgent-for-linus' of git://git./linux/kernel/git/tip/tip

Pull x86 fixes from Peter Anvin:
 "Another set of fixes, the biggest bit of this is yet another tweak to
  the UEFI anti-bricking code; apparently we finally got some feedback
  from Samsung as to what makes at least their systems fail.  This set
  should actually fix the boot regressions that some other systems (e.g.
  SGI) have exhibited.

  Other than that, there is a patch to avoid a panic with particularly
  unhappy memory layouts and two minor protocol fixes which may or may
  not be manifest bugs"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Fix typo in kexec register clearing
  x86, relocs: Move __vvar_page from S_ABS to S_REL
  Modify UEFI anti-bricking code
  x86: Fix adjust_range_size_mask calling position

11 years agoMerge branch 'rcu/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck...
Linus Torvalds [Thu, 13 Jun 2013 19:36:42 +0000 (12:36 -0700)]
Merge branch 'rcu/urgent' of git://git./linux/kernel/git/paulmck/linux-rcu

Pull RCU fixes from Paul McKenney:
 "I must confess that this past merge window was not RCU's best showing.
  This series contains three more fixes for RCU regressions:

   1.   A fix to __DECLARE_TRACE_RCU() that causes it to act as an
        interrupt from idle rather than as a task switch from idle.
        This change is needed due to the recent use of _rcuidle()
        tracepoints that can be invoked from interrupt handlers as well
        as from idle.  Without this fix, invoking _rcuidle() tracepoints
        from interrupt handlers results in splats and (more seriously)
        confusion on RCU's part as to whether a given CPU is idle or not.
        This confusion can in turn result in too-short grace periods and
        therefore random memory corruption.

   2.   A fix to a subtle deadlock that could result due to RCU doing
        a wakeup while holding one of its rcu_node structure's locks.
        Although the probability of occurrence is low, it really
        does happen.  The fix, courtesy of Steven Rostedt, uses
        irq_work_queue() to avoid the deadlock.

   3.   A fix to a silent deadlock (invisible to lockdep) due to the
        interaction of timeouts posted by RCU debug code enabled by
        CONFIG_PROVE_RCU_DELAY=y, grace-period initialization, and CPU
        hotplug operations.  This will not occur in production kernels,
        but really does occur in randconfig testing.  Diagnosis courtesy
        of Steven Rostedt"

* 'rcu/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu:
  rcu: Fix deadlock with CPU hotplug, RCU GP init, and timer migration
  rcu: Don't call wakeup() with rcu_node structure ->lock held
  trace: Allow idle-safe tracepoints to be called from irq

11 years agoMerge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Linus Torvalds [Thu, 13 Jun 2013 18:02:31 +0000 (11:02 -0700)]
Merge branch 'for-linus' of git://git./linux/kernel/git/s390/linux

Pull s390 fixes from Martin Schwidefsky:
 "Three kvm related memory management fixes, a fix for show_trace, a fix
  for early console output and a patch from Ben to help prevent compile
  errors in regard to irq functions (or our lack thereof)"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/pci: Implement IRQ functions if !PCI
  s390/sclp: fix new line detection
  s390/pgtable: make pgste lock an explicit barrier
  s390/pgtable: Save pgste during modify_prot_start/commit
  s390/dumpstack: fix address ranges for asynchronous and panic stack
  s390/pgtable: Fix guest overindication for change bit

11 years agoMerge tag 'asoc-v3.10-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie...
Linus Torvalds [Thu, 13 Jun 2013 17:18:33 +0000 (10:18 -0700)]
Merge tag 'asoc-v3.10-rc5' of git://git./linux/kernel/git/broonie/sound

Pull ASoC sound updates from Mark Brown:
 "Takashi is travelling at the minute and it'd be good to get the
  MAINTAINERS update in here merged so sending directly.

  As well as the usual driver specifics we've got a couple of core fixes
  here, one fixing capabilities for unidirectional streams and the other
  fixing suspend while audio streams are active.

  The suspend fix is a little involved but mostly as a result of
  removing some special casing that was doing the wrong thing."

* tag 'asoc-v3.10-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound:
  ASoC: tlv320aic3x: Remove deadlock from snd_soc_dapm_put_volsw_aic3x()
  ASoC: dapm: Treat DAI widgets like AIF widgets for power
  ASoC: arizona: Correct AEC loopback enable
  ASoC: pcm: Require both CODEC and CPU support when declaring stream caps
  MAINTAINERS: Remove myself from Wolfson maintainers
  ASoC: wm8994: Ensure microphone detection state is reset on removal
  ASoC: wm8994: Avoid leaking pm_runtime reference on removed jack race
  ASoC: cs42l52: fix hp_gain_enum shift value.
  ASoC: cs42l52: use correct PCM mixer TLV dB scale to match datasheet.

11 years agoMerge tag 'md-3.10-fixes' of git://neil.brown.name/md
Linus Torvalds [Thu, 13 Jun 2013 17:13:29 +0000 (10:13 -0700)]
Merge tag 'md-3.10-fixes' of git://neil.brown.name/md

Pull md bugfixes from Neil Brown:
 "A few bugfixes for md

  Some tagged for -stable"

* tag 'md-3.10-fixes' of git://neil.brown.name/md:
  md/raid1,5,10: Disable WRITE SAME until a recovery strategy is in place
  md/raid1,raid10: use freeze_array in place of raise_barrier in various places.
  md/raid1: consider WRITE as successful only if at least one non-Faulty and non-rebuilding drive completed it.
  md: md_stop_writes() should always freeze recovery.

11 years agoturbostat: Increase output buffer size to accommodate C8-C10
Josh Triplett [Thu, 13 Jun 2013 00:26:37 +0000 (17:26 -0700)]
turbostat: Increase output buffer size to accommodate C8-C10

On platforms with C8-C10 support, the additional C-states cause
turbostat to overrun its output buffer of 128 bytes per CPU.  Increase
this to 256 bytes per CPU.

[ As a bugfix, this should go into 3.10; however, since the C8-C10
  support didn't go in until after 3.9, this need not go into any stable
  kernel. ]

Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agoMerge tag 'efi-urgent' into x86/urgent
H. Peter Anvin [Thu, 13 Jun 2013 15:59:23 +0000 (08:59 -0700)]
Merge tag 'efi-urgent' into x86/urgent

 * More tweaking to the EFI variable anti-bricking algorithm. Quite a
   few users were reporting boot regressions in v3.9. This has now been
   fixed with a more accurate "minimum storage requirement to avoid
   bricking" value from Samsung (5K instead of 50%) and code to trigger
   garbage collection when we near our limit - Matthew Garrett.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
11 years agomd/raid1,5,10: Disable WRITE SAME until a recovery strategy is in place
H. Peter Anvin [Wed, 12 Jun 2013 14:37:43 +0000 (07:37 -0700)]
md/raid1,5,10: Disable WRITE SAME until a recovery strategy is in place

There are cases where the kernel will believe that the WRITE SAME
command is supported by a block device which does not, in fact,
support WRITE SAME.  This currently happens for SATA drivers behind a
SAS controller, but there are probably a hundred other ways that can
happen, including drive firmware bugs.

After receiving an error for WRITE SAME the block layer will retry the
request as a plain write of zeroes, but mdraid will consider the
failure as fatal and consider the drive failed.  This has the effect
that all the mirrors containing a specific set of data are each
offlined in very rapid succession resulting in data loss.

However, just bouncing the request back up to the block layer isn't
ideal either, because the whole initial request-retry sequence should
be inside the write bitmap fence, which probably means that md needs
to do its own conversion of WRITE SAME to write zero.

Until the failure scenario has been sorted out, disable WRITE SAME for
raid1, raid5, and raid10.

[neilb: added raid5]

This patch is appropriate for any -stable since 3.7 when write_same
support was added.

Cc: stable@vger.kernel.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
11 years agomd/raid1,raid10: use freeze_array in place of raise_barrier in various places.
NeilBrown [Wed, 12 Jun 2013 01:01:22 +0000 (11:01 +1000)]
md/raid1,raid10: use freeze_array in place of raise_barrier in various places.

Various places in raid1 and raid10 are calling raise_barrier when they
really should call freeze_array.
The former is only intended to be called from "make_request".
The later has extra checks for 'nr_queued' and makes a call to
flush_pending_writes(), so it is safe to call it from within the
management thread.

Using raise_barrier will sometimes deadlock.  Using freeze_array
should not.

As 'freeze_array' currently expects one request to be pending (in
handle_read_error - the only previous caller), we need to pass
it the number of pending requests (extra) to ignore.

The deadlock was made particularly noticeable by commits
050b66152f87c7 (raid10) and 6b740b8d79252f13 (raid1) which
appeared in 3.4, so the fix is appropriate for any -stable
kernel since then.

This patch probably won't apply directly to some early kernels and
will need to be applied by hand.

Cc: stable@vger.kernel.org
Reported-by: Alexander Lyakas <alex.bolshoy@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
11 years agomd/raid1: consider WRITE as successful only if at least one non-Faulty and non-rebuil...
Alex Lyakas [Tue, 4 Jun 2013 17:42:21 +0000 (20:42 +0300)]
md/raid1: consider WRITE as successful only if at least one non-Faulty and non-rebuilding drive completed it.

Without that fix, the following scenario could happen:

- RAID1 with drives A and B; drive B was freshly-added and is rebuilding
- Drive A fails
- WRITE request arrives to the array. It is failed by drive A, so
r1_bio is marked as R1BIO_WriteError, but the rebuilding drive B
succeeds in writing it, so the same r1_bio is marked as
R1BIO_Uptodate.
- r1_bio arrives to handle_write_finished, badblocks are disabled,
md_error()->error() does nothing because we don't fail the last drive
of raid1
- raid_end_bio_io()  calls call_bio_endio()
- As a result, in call_bio_endio():
        if (!test_bit(R1BIO_Uptodate, &r1_bio->state))
                clear_bit(BIO_UPTODATE, &bio->bi_flags);
this code doesn't clear the BIO_UPTODATE flag, and the whole master
WRITE succeeds, back to the upper layer.

So we returned success to the upper layer, even though we had written
the data onto the rebuilding drive only. But when we want to read the
data back, we would not read from the rebuilding drive, so this data
is lost.

[neilb - applied identical change to raid10 as well]

This bug can result in lost data, so it is suitable for any
-stable kernel.

Cc: stable@vger.kernel.org
Signed-off-by: Alex Lyakas <alex@zadarastorage.com>
Signed-off-by: NeilBrown <neilb@suse.de>
11 years agomd: md_stop_writes() should always freeze recovery.
NeilBrown [Wed, 8 May 2013 23:48:30 +0000 (09:48 +1000)]
md: md_stop_writes() should always freeze recovery.

__md_stop_writes() will currently sometimes freeze recovery.
So any caller must be ready for that to happen, and indeed they are.

However if __md_stop_writes() doesn't freeze_recovery, then
a recovery could start before mddev_suspend() is called, which
could be awkward.  This can particularly cause problems or dm-raid.

So change __md_stop_writes() to always freeze recovery.  This is safe
and more predicatable.

Reported-by: Brassow Jonathan <jbrassow@redhat.com>
Tested-by: Brassow Jonathan <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
11 years agoMerge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Linus Torvalds [Thu, 13 Jun 2013 00:18:29 +0000 (17:18 -0700)]
Merge git://git./linux/kernel/git/davem/net

Pull networking update from David Miller:

 1) Fix dump iterator in nfnl_acct_dump() and ctnl_timeout_dump() to
    dump all objects properly, from Pablo Neira Ayuso.

 2) xt_TCPMSS must use the default MSS of 536 when no MSS TCP option is
    present.  Fix from Phil Oester.

 3) qdisc_get_rtab() looks for an existing matching rate table and uses
    that instead of creating a new one.  However, it's key matching is
    incomplete, it fails to check to make sure the ->data[] array is
    identical too.  Fix from Eric Dumazet.

 4) ip_vs_dest_entry isn't fully initialized before copying back to
    userspace, fix from Dan Carpenter.

 5) Fix ubuf reference counting regression in vhost_net, from Jason
    Wang.

 6) When sock_diag dumps a socket filter back to userspace, we have to
    translate it out of the kernel's internal representation first.
    From Nicolas Dichtel.

 7) davinci_mdio holds a spinlock while calling pm_runtime, which
    sleeps.  Fix from Sebastian Siewior.

 8) Timeout check in sh_eth_check_reset is off by one, from Sergei
    Shtylyov.

 9) If sctp socket init fails, we can NULL deref during cleanup.  Fix
    from Daniel Borkmann.

10) netlink_mmap() does not propagate errors properly, from Patrick
    McHardy.

11) Disable powersave and use minstrel by default in ath9k.  From Sujith
    Manoharan.

12) Fix a regression in that SOCK_ZEROCOPY is not set on tuntap sockets
    which prevents vhost from being able to use zerocopy.  From Jason
    Wang.

13) Fix race between port lookup and TX path in team driver, from Jiri
    Pirko.

14) Missing length checks in bluetooth L2CAP packet parsing, from Johan
    Hedberg.

15) rtlwifi fails to connect to networking using any encryption method
    other than WPA2.  Fix from Larry Finger.

16) Fix iwlegacy build due to incorrect CONFIG_* ifdeffing for power
    management stuff.  From Yijing Wang.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (35 commits)
  b43: stop format string leaking into error msgs
  ath9k: Use minstrel rate control by default
  Revert "ath9k_hw: Update rx gain initval to improve rx sensitivity"
  ath9k: Disable PowerSave by default
  net: wireless: iwlegacy: fix build error for il_pm_ops
  rtlwifi: Fix a false leak indication for PCI devices
  wl12xx/wl18xx: scan all 5ghz channels
  wl12xx: increase minimum singlerole firmware version required
  wl12xx: fix minimum required firmware version for wl127x multirole
  rtlwifi: rtl8192cu: Fix problem in connecting to WEP or WPA(1) networks
  mwifiex: debugfs: Fix out of bounds array access
  Bluetooth: Fix mgmt handling of power on failures
  Bluetooth: Fix missing length checks for L2CAP signalling PDUs
  Bluetooth: btmrvl: support Marvell Bluetooth device SD8897
  Bluetooth: Fix checks for LE support on LE-only controllers
  team: fix checks in team_get_first_port_txable_rcu()
  team: move add to port list before port enablement
  team: check return value of team_get_port_by_index_rcu() for NULL
  tuntap: set SOCK_ZEROCOPY flag during open
  netlink: fix error propagation in netlink_mmap()
  ...

11 years agoMerge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid
Linus Torvalds [Thu, 13 Jun 2013 00:08:49 +0000 (17:08 -0700)]
Merge branch 'for-linus' of git://git./linux/kernel/git/jikos/hid

Pull input layer bugfix from Jiri Kosina:
 "Memory leak regression fix from Benjamin Tissoires"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid:
  HID: multitouch: prevent memleak with the allocated name

11 years agoMerge branch 'for-linus' of git://git.kernel.dk/linux-block
Linus Torvalds [Wed, 12 Jun 2013 23:42:39 +0000 (16:42 -0700)]
Merge branch 'for-linus' of git://git.kernel.dk/linux-block

Pull block layer fixes from Jens Axboe:
 "Outside of bcache (which really isn't super big), these are all
  few-liners.  There are a few important fixes in here:

   - Fix blk pm sleeping when holding the queue lock

   - A small collection of bcache fixes that have been done and tested
     since bcache was included in this merge window.

   - A fix for a raid5 regression introduced with the bio changes.

   - Two important fixes for mtip32xx, fixing an oops and potential data
     corruption (or hang) due to wrong bio iteration on stacked devices."

* 'for-linus' of git://git.kernel.dk/linux-block:
  scatterlist: sg_set_buf() argument must be in linear mapping
  raid5: Initialize bi_vcnt
  pktcdvd: silence static checker warning
  block: remove refs to XD disks from documentation
  blkpm: avoid sleep when holding queue lock
  mtip32xx: Correctly handle bio->bi_idx != 0 conditions
  mtip32xx: Fix NULL pointer dereference during module unload
  bcache: Fix error handling in init code
  bcache: clarify free/available/unused space
  bcache: drop "select CLOSURES"
  bcache: Fix incompatible pointer type warning

11 years agoMerge branch 'akpm' (updates from Andrew Morton)
Linus Torvalds [Wed, 12 Jun 2013 23:29:53 +0000 (16:29 -0700)]
Merge branch 'akpm' (updates from Andrew Morton)

Merge misc fixes from Andrew Morton:
 "Bunch of fixes and one little addition to math64.h"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (27 commits)
  include/linux/math64.h: add div64_ul()
  mm: memcontrol: fix lockless reclaim hierarchy iterator
  frontswap: fix incorrect zeroing and allocation size for frontswap_map
  kernel/audit_tree.c:audit_add_tree_rule(): protect `rule' from kill_rules()
  mm: migration: add migrate_entry_wait_huge()
  ocfs2: add missing lockres put in dlm_mig_lockres_handler
  mm/page_alloc.c: fix watermark check in __zone_watermark_ok()
  drivers/misc/sgi-gru/grufile.c: fix info leak in gru_get_config_info()
  aio: fix io_destroy() regression by using call_rcu()
  rtc-at91rm9200: use shadow IMR on at91sam9x5
  rtc-at91rm9200: add shadow interrupt mask
  rtc-at91rm9200: refactor interrupt-register handling
  rtc-at91rm9200: add configuration support
  rtc-at91rm9200: add match-table compile guard
  fs/ocfs2/namei.c: remove unecessary ERROR when removing non-empty directory
  swap: avoid read_swap_cache_async() race to deadlock while waiting on discard I/O completion
  drivers/rtc/rtc-twl.c: fix missing device_init_wakeup() when booted with device tree
  cciss: fix broken mutex usage in ioctl
  audit: wait_for_auditd() should use TASK_UNINTERRUPTIBLE
  drivers/rtc/rtc-cmos.c: fix accidentally enabling rtc channel
  ...

11 years agoinclude/linux/math64.h: add div64_ul()
Alex Shi [Wed, 12 Jun 2013 21:05:10 +0000 (14:05 -0700)]
include/linux/math64.h: add div64_ul()

There is div64_long() to handle the s64/long division, but no mocro do
u64/ul division.  It is necessary in some scenarios, so add this
function.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Alex Shi <alex.shi@intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agomm: memcontrol: fix lockless reclaim hierarchy iterator
Johannes Weiner [Wed, 12 Jun 2013 21:05:09 +0000 (14:05 -0700)]
mm: memcontrol: fix lockless reclaim hierarchy iterator

The lockless reclaim hierarchy iterator currently has a misplaced
barrier that can lead to use-after-free crashes.

The reclaim hierarchy iterator consist of a sequence count and a
position pointer that are read and written locklessly, with memory
barriers enforcing ordering.

The write side sets the position pointer first, then updates the
sequence count to "publish" the new position.  Likewise, the read side
must read the sequence count first, then the position.  If the sequence
count is up to date, it's guaranteed that the position is up to date as
well:

  writer:                         reader:
  iter->position = position       if iter->sequence == expected:
  smp_wmb()                           smp_rmb()
  iter->sequence = sequence           position = iter->position

However, the read side barrier is currently misplaced, which can lead to
dereferencing stale position pointers that no longer point to valid
memory.  Fix this.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reported-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Tejun Heo <tj@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Glauber Costa <glommer@parallels.com>
Cc: <stable@kernel.org> [3.10+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agofrontswap: fix incorrect zeroing and allocation size for frontswap_map
Akinobu Mita [Wed, 12 Jun 2013 21:05:08 +0000 (14:05 -0700)]
frontswap: fix incorrect zeroing and allocation size for frontswap_map

The bitmap accessed by bitops must have enough size to hold the required
numbers of bits rounded up to a multiple of BITS_PER_LONG.  And the
bitmap must not be zeroed by memset() if the number of bits cleared is
not a multiple of BITS_PER_LONG.

This fixes incorrect zeroing and allocation size for frontswap_map.  The
incorrect zeroing part doesn't cause any problem because frontswap_map
is freed just after zeroing.  But the wrongly calculated allocation size
may cause the problem.

For 32bit systems, the allocation size of frontswap_map is about twice
as large as required size.  For 64bit systems, the allocation size is
smaller than requeired if the number of bits is not a multiple of
BITS_PER_LONG.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agokernel/audit_tree.c:audit_add_tree_rule(): protect `rule' from kill_rules()
Chen Gang [Wed, 12 Jun 2013 21:05:07 +0000 (14:05 -0700)]
kernel/audit_tree.c:audit_add_tree_rule(): protect `rule' from kill_rules()

audit_add_tree_rule() must set 'rule->tree = NULL;' firstly, to protect
the rule itself freed in kill_rules().

The reason is when it is killed, the 'rule' itself may have already
released, we should not access it.  one example: we add a rule to an
inode, just at the same time the other task is deleting this inode.

The work flow for adding a rule:

    audit_receive() -> (need audit_cmd_mutex lock)
      audit_receive_skb() ->
        audit_receive_msg() ->
          audit_receive_filter() ->
            audit_add_rule() ->
              audit_add_tree_rule() -> (need audit_filter_mutex lock)
                ...
                unlock audit_filter_mutex
                get_tree()
                ...
                iterate_mounts() -> (iterate all related inodes)
                  tag_mount() ->
                    tag_trunk() ->
                      create_trunk() -> (assume it is 1st rule)
                        fsnotify_add_mark() ->
                          fsnotify_add_inode_mark() ->  (add mark to inode->i_fsnotify_marks)
                        ...
                        get_tree(); (each inode will get one)
                ...
                lock audit_filter_mutex

The work flow for deleting an inode:

    __destroy_inode() ->
     fsnotify_inode_delete() ->
       __fsnotify_inode_delete() ->
        fsnotify_clear_marks_by_inode() ->  (get mark from inode->i_fsnotify_marks)
          fsnotify_destroy_mark() ->
           fsnotify_destroy_mark_locked() ->
             audit_tree_freeing_mark() ->
               evict_chunk() ->
                 ...
                 tree->goner = 1
                 ...
                 kill_rules() ->   (assume current->audit_context == NULL)
                   call_rcu() ->   (rule->tree != NULL)
                     audit_free_rule_rcu() ->
                       audit_free_rule()
                 ...
                 audit_schedule_prune() ->  (assume current->audit_context == NULL)
                   kthread_run() ->    (need audit_cmd_mutex and audit_filter_mutex lock)
                     prune_one() ->    (delete it from prue_list)
                       put_tree(); (match the original get_tree above)

Signed-off-by: Chen Gang <gang.chen@asianux.com>
Cc: Eric Paris <eparis@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agomm: migration: add migrate_entry_wait_huge()
Naoya Horiguchi [Wed, 12 Jun 2013 21:05:04 +0000 (14:05 -0700)]
mm: migration: add migrate_entry_wait_huge()

When we have a page fault for the address which is backed by a hugepage
under migration, the kernel can't wait correctly and do busy looping on
hugepage fault until the migration finishes.  As a result, users who try
to kick hugepage migration (via soft offlining, for example) occasionally
experience long delay or soft lockup.

This is because pte_offset_map_lock() can't get a correct migration entry
or a correct page table lock for hugepage.  This patch introduces
migration_entry_wait_huge() to solve this.

Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: <stable@vger.kernel.org> [2.6.35+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agoocfs2: add missing lockres put in dlm_mig_lockres_handler
Xue jiufei [Wed, 12 Jun 2013 21:05:03 +0000 (14:05 -0700)]
ocfs2: add missing lockres put in dlm_mig_lockres_handler

dlm_mig_lockres_handler() is missing a dlm_lockres_put() on an error path.

Signed-off-by: joyce <xuejiufei@huawei.com>
Reviewed-by: shencanquan <shencanquan@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agomm/page_alloc.c: fix watermark check in __zone_watermark_ok()
Tomasz Stanislawski [Wed, 12 Jun 2013 21:05:02 +0000 (14:05 -0700)]
mm/page_alloc.c: fix watermark check in __zone_watermark_ok()

The watermark check consists of two sub-checks.  The first one is:

if (free_pages <= min + lowmem_reserve)
return false;

The check assures that there is minimal amount of RAM in the zone.  If
CMA is used then the free_pages is reduced by the number of free pages
in CMA prior to the over-mentioned check.

if (!(alloc_flags & ALLOC_CMA))
free_pages -= zone_page_state(z, NR_FREE_CMA_PAGES);

This prevents the zone from being drained from pages available for
non-movable allocations.

The second check prevents the zone from getting too fragmented.

for (o = 0; o < order; o++) {
free_pages -= z->free_area[o].nr_free << o;
min >>= 1;
if (free_pages <= min)
return false;
}

The field z->free_area[o].nr_free is equal to the number of free pages
including free CMA pages.  Therefore the CMA pages are subtracted twice.
This may cause a false positive fail of __zone_watermark_ok() if the CMA
area gets strongly fragmented.  In such a case there are many 0-order
free pages located in CMA.  Those pages are subtracted twice therefore
they will quickly drain free_pages during the check against
fragmentation.  The test fails even though there are many free non-cma
pages in the zone.

This patch fixes this issue by subtracting CMA pages only for a purpose of
(free_pages <= min + lowmem_reserve) check.

Laura said:

  We were observing allocation failures of higher order pages (order 5 =
  128K typically) under tight memory conditions resulting in driver
  failure.  The output from the page allocation failure showed plenty of
  free pages of the appropriate order/type/zone and mostly CMA pages in
  the lower orders.

  For full disclosure, we still observed some page allocation failures
  even after applying the patch but the number was drastically reduced and
  those failures were attributed to fragmentation/other system issues.

Signed-off-by: Tomasz Stanislawski <t.stanislaws@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Tested-by: Laura Abbott <lauraa@codeaurora.org>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: <stable@vger.kernel.org> [3.7+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agodrivers/misc/sgi-gru/grufile.c: fix info leak in gru_get_config_info()
Dan Carpenter [Wed, 12 Jun 2013 21:05:00 +0000 (14:05 -0700)]
drivers/misc/sgi-gru/grufile.c: fix info leak in gru_get_config_info()

The "info.fill" array isn't initialized so it can leak uninitialized stack
information to user space.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Robin Holt <holt@sgi.com>
Acked-by: Dimitri Sivanich <sivanich@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agoaio: fix io_destroy() regression by using call_rcu()
Kent Overstreet [Wed, 12 Jun 2013 21:04:59 +0000 (14:04 -0700)]
aio: fix io_destroy() regression by using call_rcu()

There was a regression introduced by 36f5588905c1 ("aio: refcounting
cleanup"), reported by Jens Axboe - the refcounting cleanup switched to
using RCU in the shutdown path, but the synchronize_rcu() was done in
the context of the io_destroy() syscall greatly increasing the time it
could block.

This patch switches it to call_rcu() and makes shutdown asynchronous
(more asynchronous than it was originally; before the refcount changes
io_destroy() would still wait on pending kiocbs).

Note that there's a global quota on the max outstanding kiocbs, and that
quota must be manipulated synchronously; otherwise io_setup() could
return -EAGAIN when there isn't quota available, and userspace won't
have any way of waiting until shutdown of the old kioctxs has finished
(besides busy looping).

So we release our quota before kioctx shutdown has finished, which
should be fine since the quota never corresponded to anything real
anyways.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
Cc: Zach Brown <zab@redhat.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Reported-by: Jens Axboe <axboe@kernel.dk>
Tested-by: Jens Axboe <axboe@kernel.dk>
Cc: Asai Thambi S P <asamymuthupa@micron.com>
Cc: Selvan Mani <smani@micron.com>
Cc: Sam Bradshaw <sbradshaw@micron.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
Tested-by: Benjamin LaHaise <bcrl@kvack.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agortc-at91rm9200: use shadow IMR on at91sam9x5
Johan Hovold [Wed, 12 Jun 2013 21:04:57 +0000 (14:04 -0700)]
rtc-at91rm9200: use shadow IMR on at91sam9x5

Add support for the at91sam9x5-family which must use the shadow
interrupt mask due to a hardware issue (causing RTC_IMR to always be
zero).

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Cc: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Cc: Ludovic Desroches <ludovic.desroches@atmel.com>
Cc: Robert Nelson <Robert.Nelson@digikey.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agortc-at91rm9200: add shadow interrupt mask
Johan Hovold [Wed, 12 Jun 2013 21:04:56 +0000 (14:04 -0700)]
rtc-at91rm9200: add shadow interrupt mask

Add shadow interrupt-mask register which can be used on SoCs where the
actual hardware register is broken.

Note that some care needs to be taken to make sure the shadow mask
corresponds to the actual hardware state.  The added overhead is not an
issue for the non-broken SoCs due to the relatively infrequent
interrupt-mask updates.  We do, however, only use the shadow mask value
as a fall-back when it actually needed as there is still a theoretical
possibility that the mask is incorrect (see the code for details).

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Cc: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Cc: Ludovic Desroches <ludovic.desroches@atmel.com>
Cc: Robert Nelson <Robert.Nelson@digikey.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agortc-at91rm9200: refactor interrupt-register handling
Johan Hovold [Wed, 12 Jun 2013 21:04:55 +0000 (14:04 -0700)]
rtc-at91rm9200: refactor interrupt-register handling

Add accessors for the interrupt register.

This will allow us to easily add a shadow interrupt-mask register to use
on SoCs where the interrupt-mask register cannot be used.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Cc: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Cc: Ludovic Desroches <ludovic.desroches@atmel.com>
Cc: Robert Nelson <Robert.Nelson@digikey.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agortc-at91rm9200: add configuration support
Johan Hovold [Wed, 12 Jun 2013 21:04:53 +0000 (14:04 -0700)]
rtc-at91rm9200: add configuration support

Add configuration support which can be used to implement SoC-specific
workarounds for broken hardware.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Cc: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Cc: Ludovic Desroches <ludovic.desroches@atmel.com>
Cc: Robert Nelson <Robert.Nelson@digikey.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agortc-at91rm9200: add match-table compile guard
Johan Hovold [Wed, 12 Jun 2013 21:04:52 +0000 (14:04 -0700)]
rtc-at91rm9200: add match-table compile guard

The members of Atmel's at91sam9x5 family (9x5) have a broken RTC
interrupt mask register (AT91_RTC_IMR).  It does not reflect enabled
interrupts but instead always returns zero.

The kernel's rtc-at91rm9200 driver handles the RTC for the 9x5 family.
Currently when the date/time is set, an interrupt is generated and this
driver neglects to handle the interrupt.  The kernel complains about the
un-handled interrupt and disables it henceforth.  This not only breaks
the RTC function, but since that interrupt is shared (Atmel's SYS
interrupt) then other things break as well (e.g.  the debug port no
longer accepts characters).

Tested on the at91sam9g25.  Bug confirmed by Atmel.

This patch (of 5):

Add missing match-table compile guard.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Cc: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Cc: Ludovic Desroches <ludovic.desroches@atmel.com>
Cc: Robert Nelson <Robert.Nelson@digikey.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agofs/ocfs2/namei.c: remove unecessary ERROR when removing non-empty directory
Goldwyn Rodrigues [Wed, 12 Jun 2013 21:04:51 +0000 (14:04 -0700)]
fs/ocfs2/namei.c: remove unecessary ERROR when removing non-empty directory

While removing a non-empty directory, the kernel dumps a message:

  (rmdir,21743,1):ocfs2_unlink:953 ERROR: status = -39

Suppress the error message from being printed in the dmesg so users
don't panic.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Acked-by: Sunil Mushran <sunil.mushran@gmail.com>
Reviewed-by: Jie Liu <jeff.liu@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agoswap: avoid read_swap_cache_async() race to deadlock while waiting on discard I/O...
Rafael Aquini [Wed, 12 Jun 2013 21:04:49 +0000 (14:04 -0700)]
swap: avoid read_swap_cache_async() race to deadlock while waiting on discard I/O completion

read_swap_cache_async() can race against get_swap_page(), and stumble
across a SWAP_HAS_CACHE entry in the swap map whose page wasn't brought
into the swapcache yet.

This transient swap_map state is expected to be transitory, but the
actual placement of discard at scan_swap_map() inserts a wait for I/O
completion thus making the thread at read_swap_cache_async() to loop
around its -EEXIST case, while the other end at get_swap_page() is
scheduled away at scan_swap_map().  This can leave the system deadlocked
if the I/O completion happens to be waiting on the CPU waitqueue where
read_swap_cache_async() is busy looping and !CONFIG_PREEMPT.

This patch introduces a cond_resched() call to make the aforementioned
read_swap_cache_async() busy loop condition to bail out when necessary,
thus avoiding the subtle race window.

Signed-off-by: Rafael Aquini <aquini@redhat.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Shaohua Li <shli@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agodrivers/rtc/rtc-twl.c: fix missing device_init_wakeup() when booted with device tree
Tony Lindgren [Wed, 12 Jun 2013 21:04:48 +0000 (14:04 -0700)]
drivers/rtc/rtc-twl.c: fix missing device_init_wakeup() when booted with device tree

When booted in legacy mode device_init_wakeup() gets called by
drivers/mfd/twl-core.c when the children are initialized.  However, when
booted using device tree, the children are created with
of_platform_populate() instead add_children().

This means that the RTC driver will not have device_init_wakeup() set,
and we need to call it from the driver probe like RTC drivers typically
do.

Without this we cannot test PM wake-up events on omaps for cases where
there may not be any physical wake-up event.

Signed-off-by: Tony Lindgren <tony@atomide.com>
Reported-by: Kevin Hilman <khilman@linaro.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Jingoo Han <jg1.han@samsung.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agocciss: fix broken mutex usage in ioctl
Stephen M. Cameron [Wed, 12 Jun 2013 21:04:47 +0000 (14:04 -0700)]
cciss: fix broken mutex usage in ioctl

If a new logical drive is added and the CCISS_REGNEWD ioctl is invoked
(as is normal with the Array Configuration Utility) the process will
hang as below.  It attempts to acquire the same mutex twice, once in
do_ioctl() and once in cciss_unlocked_open().  The BKL was recursive,
the mutex isn't.

  Linux version 3.10.0-rc2 (scameron@localhost.localdomain) (gcc version 4.4.7 20120313 (Red Hat 4.4.7-3) (GCC) ) #1 SMP Fri May 24 14:32:12 CDT 2013
  [...]
  acu             D 0000000000000001     0  3246   3191 0x00000080
  Call Trace:
    schedule+0x29/0x70
    schedule_preempt_disabled+0xe/0x10
    __mutex_lock_slowpath+0x17b/0x220
    mutex_lock+0x2b/0x50
    cciss_unlocked_open+0x2f/0x110 [cciss]
    __blkdev_get+0xd3/0x470
    blkdev_get+0x5c/0x1e0
    register_disk+0x182/0x1a0
    add_disk+0x17c/0x310
    cciss_add_disk+0x13a/0x170 [cciss]
    cciss_update_drive_info+0x39b/0x480 [cciss]
    rebuild_lun_table+0x258/0x370 [cciss]
    cciss_ioctl+0x34f/0x470 [cciss]
    do_ioctl+0x49/0x70 [cciss]
    __blkdev_driver_ioctl+0x28/0x30
    blkdev_ioctl+0x200/0x7b0
    block_ioctl+0x3c/0x40
    do_vfs_ioctl+0x89/0x350
    SyS_ioctl+0xa1/0xb0
    system_call_fastpath+0x16/0x1b

This mutex usage was added into the ioctl path when the big kernel lock
was removed.  As it turns out, these paths are all thread safe anyway
(or can easily be made so) and we don't want ioctl() to be single
threaded in any case.

Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Mike Miller <mike.miller@hp.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agoaudit: wait_for_auditd() should use TASK_UNINTERRUPTIBLE
Oleg Nesterov [Wed, 12 Jun 2013 21:04:46 +0000 (14:04 -0700)]
audit: wait_for_auditd() should use TASK_UNINTERRUPTIBLE

audit_log_start() does wait_for_auditd() in a loop until
audit_backlog_wait_time passes or audit_skb_queue has a room.

If signal_pending() is true this becomes a busy-wait loop, schedule() in
TASK_INTERRUPTIBLE won't block.

Thanks to Guy for fully investigating and explaining the problem.

(akpm: that'll cause the system to lock up on a non-preemptible
uniprocessor kernel)

(Guy: "Our customer was in fact running a uniprocessor machine, and they
reported a system hang.")

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: Guy Streeter <streeter@redhat.com>
Cc: Eric Paris <eparis@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agodrivers/rtc/rtc-cmos.c: fix accidentally enabling rtc channel
Derek Basehore [Wed, 12 Jun 2013 21:04:45 +0000 (14:04 -0700)]
drivers/rtc/rtc-cmos.c: fix accidentally enabling rtc channel

During resume, we call hpet_rtc_timer_init after masking an irq bit in
hpet.  This will cause the call to hpet_disable_rtc_channel to be undone
if RTC_AIE is the only bit not masked.

Allowing the cmos interrupt handler to run before resuming caused some
issues where the timer for the alarm was not removed.  This would cause
other, later timers to not be cleared, so utilities such as hwclock
would time out when waiting for the update interrupt.

[akpm@linux-foundation.org: coding-style tweak]
Signed-off-by: Derek Basehore <dbasehore@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agodrivers/rtc/rtc-tps6586x.c: device wakeup flags correction
Dmitry Osipenko [Wed, 12 Jun 2013 21:04:44 +0000 (14:04 -0700)]
drivers/rtc/rtc-tps6586x.c: device wakeup flags correction

Use device_init_wakeup() instead of device_set_wakeup_capable() and move
it before rtc dev registering.  This fixes alarmtimer not registered
when tps6586x rtc is the only wakeup compatible rtc in the system.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Cc: Laxman Dewangan <ldewangan@nvidia.com>
Cc: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agomemcg: don't initialize kmem-cache destroying work for root caches
Andrey Vagin [Wed, 12 Jun 2013 21:04:42 +0000 (14:04 -0700)]
memcg: don't initialize kmem-cache destroying work for root caches

struct memcg_cache_params has a union.  Different parts of this union
are used for root and non-root caches.  A part with destroying work is
used only for non-root caches.

  BUG: unable to handle kernel paging request at 0000000fffffffe0
  IP: kmem_cache_alloc+0x41/0x1f0
  Modules linked in: netlink_diag af_packet_diag udp_diag tcp_diag inet_diag unix_diag ip6table_filter ip6_tables i2c_piix4 virtio_net virtio_balloon microcode i2c_core pcspkr floppy
  CPU: 0 PID: 1929 Comm: lt-vzctl Tainted: G      D      3.10.0-rc1+ #2
  Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
  RIP: kmem_cache_alloc+0x41/0x1f0
  Call Trace:
   getname_flags.part.34+0x30/0x140
   getname+0x38/0x60
   do_sys_open+0xc5/0x1e0
   SyS_open+0x22/0x30
   system_call_fastpath+0x16/0x1b
  Code: f4 53 48 83 ec 18 8b 05 8e 53 b7 00 4c 8b 4d 08 21 f0 a8 10 74 0d 4c 89 4d c0 e8 1b 76 4a 00 4c 8b 4d c0 e9 92 00 00 00 4d 89 f5 <4d> 8b 45 00 65 4c 03 04 25 48 cd 00 00 49 8b 50 08 4d 8b 38 49
  RIP  [<ffffffff8116b641>] kmem_cache_alloc+0x41/0x1f0

Signed-off-by: Andrey Vagin <avagin@openvz.org>
Cc: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Glauber Costa <glommer@parallels.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Cc: Li Zefan <lizefan@huawei.com>
Cc: <stable@vger.kernel.org> [3.9.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agoocfs2: ocfs2_prep_new_orphaned_file() should return ret
Xiaowei.Hu [Wed, 12 Jun 2013 21:04:41 +0000 (14:04 -0700)]
ocfs2: ocfs2_prep_new_orphaned_file() should return ret

If an error occurs, for example an EIO in __ocfs2_prepare_orphan_dir,
ocfs2_prep_new_orphaned_file will release the inode_ac, then when the
caller of ocfs2_prep_new_orphaned_file gets a 0 return, it will refer to
a NULL ocfs2_alloc_context struct in the following functions.  A kernel
panic happens.

Signed-off-by: "Xiaowei.Hu" <xiaowei.hu@oracle.com>
Reviewed-by: shencanquan <shencanquan@huawei.com>
Acked-by: Sunil Mushran <sunil.mushran@gmail.com>
Cc: Joe Jin <joe.jin@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agolib/mpi/mpicoder.c: looping issue, need stop when equal to zero, found by 'EXTRA_FLAG...
Chen Gang [Wed, 12 Jun 2013 21:04:40 +0000 (14:04 -0700)]
lib/mpi/mpicoder.c: looping issue, need stop when equal to zero, found by 'EXTRA_FLAGS=-W'.

For 'while' looping, need stop when 'nbytes == 0', or will cause issue.
('nbytes' is size_t which is always bigger or equal than zero).

The related warning: (with EXTRA_CFLAGS=-W)

  lib/mpi/mpicoder.c:40:2: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits]

Signed-off-by: Chen Gang <gang.chen@asianux.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: David Howells <dhowells@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agokmsg: honor dmesg_restrict sysctl on /dev/kmsg
Kees Cook [Wed, 12 Jun 2013 21:04:39 +0000 (14:04 -0700)]
kmsg: honor dmesg_restrict sysctl on /dev/kmsg

The dmesg_restrict sysctl currently covers the syslog method for access
dmesg, however /dev/kmsg isn't covered by the same protections.  Most
people haven't noticed because util-linux dmesg(1) defaults to using the
syslog method for access in older versions.  With util-linux dmesg(1)
defaults to reading directly from /dev/kmsg.

To fix /dev/kmsg, let's compare the existing interfaces and what they
allow:

 - /proc/kmsg allows:
  - open (SYSLOG_ACTION_OPEN) if CAP_SYSLOG since it uses a destructive
    single-reader interface (SYSLOG_ACTION_READ).
  - everything, after an open.

 - syslog syscall allows:
  - anything, if CAP_SYSLOG.
  - SYSLOG_ACTION_READ_ALL and SYSLOG_ACTION_SIZE_BUFFER, if
    dmesg_restrict==0.
  - nothing else (EPERM).

The use-cases were:
 - dmesg(1) needs to do non-destructive SYSLOG_ACTION_READ_ALLs.
 - sysklog(1) needs to open /proc/kmsg, drop privs, and still issue the
   destructive SYSLOG_ACTION_READs.

AIUI, dmesg(1) is moving to /dev/kmsg, and systemd-journald doesn't
clear the ring buffer.

Based on the comments in devkmsg_llseek, it sounds like actions besides
reading aren't going to be supported by /dev/kmsg (i.e.
SYSLOG_ACTION_CLEAR), so we have a strict subset of the non-destructive
syslog syscall actions.

To this end, move the check as Josh had done, but also rename the
constants to reflect their new uses (SYSLOG_FROM_CALL becomes
SYSLOG_FROM_READER, and SYSLOG_FROM_FILE becomes SYSLOG_FROM_PROC).
SYSLOG_FROM_READER allows non-destructive actions, and SYSLOG_FROM_PROC
allows destructive actions after a capabilities-constrained
SYSLOG_ACTION_OPEN check.

 - /dev/kmsg allows:
  - open if CAP_SYSLOG or dmesg_restrict==0
  - reading/polling, after open

Addresses https://bugzilla.redhat.com/show_bug.cgi?id=903192

[akpm@linux-foundation.org: use pr_warn_once()]
Signed-off-by: Kees Cook <keescook@chromium.org>
Reported-by: Christian Kujau <lists@nerdbynature.de>
Tested-by: Josh Boyer <jwboyer@redhat.com>
Cc: Kay Sievers <kay@vrfy.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
11 years agoreboot: rigrate shutdown/reboot to boot cpu
Robin Holt [Wed, 12 Jun 2013 21:04:37 +0000 (14:04 -0700)]
reboot: rigrate shutdown/reboot to boot cpu

We recently noticed that reboot of a 1024 cpu machine takes approx 16
minutes of just stopping the cpus.  The slowdown was tracked to commit
f96972f2dc63 ("kernel/sys.c: call disable_nonboot_cpus() in
kernel_restart()").

The current implementation does all the work of hot removing the cpus
before halting the system.  We are switching to just migrating to the
boot cpu and then continuing with shutdown/reboot.

This also has the effect of not breaking x86's command line parameter
for specifying the reboot cpu.  Note, this code was shamelessly copied
from arch/x86/kernel/reboot.c with bits removed pertaining to the
reboot_cpu command line parameter.

Signed-off-by: Robin Holt <holt@sgi.com>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Cc: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Russ Anderson <rja@sgi.com>
Cc: Robin Holt <holt@sgi.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>