powerpc/watchpoint: Fix exception handling for CONFIG_HAVE_HW_BREAKPOINT=N

On powerpc, ptrace watchpoint works in one-shot mode. i.e. kernel
disables event every time it fires and user has to re-enable it.
Also, in case of ptrace watchpoint, kernel notifies ptrace user
before executing instruction.

With CONFIG_HAVE_HW_BREAKPOINT=N, kernel is missing to disable
ptrace event and thus it's causing infinite loop of exceptions.
This is especially harmful when user watches on a data which is
also read/written by kernel, eg syscall parameters. In such case,
infinite exceptions happens in kernel mode which causes soft-lockup.

Fixes: 9422de3e953d ("powerpc: Hardware breakpoints rewrite to handle non DABR breakpoint registers")
Reported-by: Pedro Miraglia Franco de Carvalho <pedromfc@linux.ibm.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200902042945.129369-6-ravi.bangoria@linux.ibm.com

powerpc/watchpoint: Move DAWR detection logic outside of hw_breakpoint.c

Power10 hw has multiple DAWRs but hw doesn't tell which DAWR caused
the exception. So we have a sw logic to detect that in hw_breakpoint.c.
But hw_breakpoint.c gets compiled only with CONFIG_HAVE_HW_BREAKPOINT=Y.
Move DAWR detection logic outside of hw_breakpoint.c so that it can be
reused when CONFIG_HAVE_HW_BREAKPOINT is not set.

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200902042945.129369-5-ravi.bangoria@linux.ibm.com

powerpc/watchpoint/ptrace: Fix SETHWDEBUG when CONFIG_HAVE_HW_BREAKPOINT=N

When kernel is compiled with CONFIG_HAVE_HW_BREAKPOINT=N, user can
still create watchpoint using PPC_PTRACE_SETHWDEBUG, with limited
functionalities. But, such watchpoints are never firing because of
the missing privilege settings. Fix that.

It's safe to set HW_BRK_TYPE_PRIV_ALL because we don't really leak
any kernel address in signal info. Setting HW_BRK_TYPE_PRIV_ALL will
also help to find scenarios when kernel accesses user memory.

Reported-by: Pedro Miraglia Franco de Carvalho <pedromfc@linux.ibm.com>
Suggested-by: Pedro Miraglia Franco de Carvalho <pedromfc@linux.ibm.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200902042945.129369-4-ravi.bangoria@linux.ibm.com

powerpc/watchpoint: Fix handling of vector instructions

Vector load/store instructions are special because they are always
aligned. Thus unaligned EA needs to be aligned down before comparing
it with watch ranges. Otherwise we might consider valid event as
invalid.

Fixes: 74c6881019b7 ("powerpc/watchpoint: Prepare handler to handle more than one watchpoint")
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200902042945.129369-3-ravi.bangoria@linux.ibm.com

powerpc/watchpoint: Fix quadword instruction handling on p10 predecessors

On p10 predecessors, watchpoint with quadword access is compared at
quadword length. If the watch range is doubleword or less than that
in a first half of quadword aligned 16 bytes, and if there is any
unaligned quadword access which will access only the 2nd half, the
handler should consider it as extraneous and emulate/single-step it
before continuing.

Fixes: 74c6881019b7 ("powerpc/watchpoint: Prepare handler to handle more than one watchpoint")
Reported-by: Pedro Miraglia Franco de Carvalho <pedromfc@linux.ibm.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200902042945.129369-2-ravi.bangoria@linux.ibm.com

powerpc/pseries/svm: Allocate SWIOTLB buffer anywhere in memory

POWER secure guests (i.e., guests which use the Protected Execution
Facility) need to use SWIOTLB to be able to do I/O with the
hypervisor, but they don't need the SWIOTLB memory to be in low
addresses since the hypervisor doesn't have any addressing limitation.

This solves a SWIOTLB initialization problem we are seeing in secure
guests with 128 GB of RAM: they are configured with 4 GB of
crashkernel reserved memory, which leaves no space for SWIOTLB in low
addresses.

To do this, we use mostly the same code as swiotlb_init(), but
allocate the buffer using memblock_alloc() instead of
memblock_alloc_low().

Fixes: 2efbc58f157a ("powerpc/pseries/svm: Force SWIOTLB for secure guests")
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200818221126.391073-1-bauerman@linux.ibm.com

powerpc/64: Make VDSO32 track COMPAT on 64-bit

When we added the VDSO32 kconfig symbol, which controls building of
the 32-bit VDSO, we made it depend on CPU_BIG_ENDIAN (for 64-bit).

That was because back then COMPAT was always enabled for 64-bit, so
depending on it would have left the 32-bit VDSO always enabled, which
we didn't want.

But since then we have made COMPAT selectable, and off by default for
ppc64le, so VDSO32 should really depend on that.

For most people this makes no difference, none of the defconfigs
change, it's only if someone is building ppc64le with COMPAT=y, they
will now also get VDSO32. If they've enabled COMPAT in order to run
32-bit binaries they presumably also want the 32-bit VDSO.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/r/20200908125850.407939-1-mpe@ellerman.id.au

Merge branch 'fixes' into next

Bring in our fixes branch for this cycle which avoids some small
conflicts with upcoming commits.

powerpc/papr_scm: Limit the readability of 'perf_stats' sysfs attribute

The newly introduced 'perf_stats' attribute uses the default access
mode of 0444, allowing non-root users to access performance stats of
an nvdimm and potentially force the kernel into issuing a large number
of expensive hypercalls. Since the information exposed by this
attribute cannot be cached it is better to ward off access to this
attribute from users who don't need to access to these performance
statistics.

Hence update the access mode of 'perf_stats' attribute to be only
readable by root users.

Fixes: 2d02bf835e57 ("powerpc/papr_scm: Fetch nvdimm performance stats from PHYP")
Reported-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200907110540.21349-1-vaibhav@linux.ibm.com

powerpc/64s: handle ISA v3.1 local copy-paste context switches

The ISA v3.1 the copy-paste facility has a new memory move functionality
which allows the copy buffer to be pasted to domestic memory (RAM) as
opposed to foreign memory (accelerator).

This means the POWER9 trick of avoiding the cp_abort on context switch if
the process had not mapped foreign memory does not work on POWER10. Do the
cp_abort unconditionally there.

KVM must also cp_abort on guest exit to prevent copy buffer state leaking
between contexts.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200825075535.224536-1-npiggin@gmail.com

powerpc: Warn about use of smt_snooze_delay

It's not done anything for a long time. Save the percpu variable, and
emit a warning to remind users to not expect it to do anything.

This uses pr_warn_once instead of pr_warn_ratelimit as testing
'ppc64_cpu --smt=off' on a 24 core / 4 SMT system showed the warning
to be noisy, as the online/offline loop is slow.

Fixes: 3fa8cad82b94 ("powerpc/pseries/cpuidle: smt-snooze-delay cleanup.")
Cc: stable@vger.kernel.org # v3.14
Signed-off-by: Joel Stanley <joel@jms.id.au>
Acked-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200902000012.3440389-1-joel@jms.id.au

powerpc/powernv: Print helpful message when cores guarded

Often the firmware will guard out cores after a crash. This often
undesirable, and is not immediately noticeable.

This adds an informative message when a CPU device tree nodes are
marked bad in the device tree.

Signed-off-by: Joel Stanley <joel@jms.id.au>
[mpe: Use an eye-catcher that's less likely to get us in trouble]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190801051630.5804-1-joel@jms.id.au

powerpc/pseries/iommu: Allow bigger 64bit window by removing default DMA window

On LoPAR "DMA Window Manipulation Calls", it's recommended to remove the
default DMA window for the device, before attempting to configure a DDW,
in order to make the maximum resources available for the next DDW to be
created.

This is a requirement for using DDW on devices in which hypervisor
allows only one DMA window.

If setting up a new DDW fails anywhere after the removal of this
default DMA window, it's needed to restore the default DMA window.
For this, an implementation of ibm,reset-pe-dma-windows rtas call is
needed:

Platforms supporting the DDW option starting with LoPAR level 2.7 implement
ibm,ddw-extensions. The first extension available (index 2) carries the
token for ibm,reset-pe-dma-windows rtas call, which is used to restore
the default DMA window for a device, if it has been deleted.

It does so by resetting the TCE table allocation for the PE to it's
boot time value, available in "ibm,dma-window" device tree node.

Signed-off-by: Leonardo Bras <leobras.c@gmail.com>
Tested-by: David Dai <zdai@linux.vnet.ibm.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200805030455.123024-5-leobras.c@gmail.com

powerpc/pseries/iommu: Move window-removing part of remove_ddw into remove_dma_window

Move the window-removing part of remove_ddw into a new function
(remove_dma_window), so it can be used to remove other DMA windows.

It's useful for removing DMA windows that don't create DIRECT64_PROPNAME
property, like the default DMA window from the device, which uses
"ibm,dma-window".

Signed-off-by: Leonardo Bras <leobras.c@gmail.com>
Tested-by: David Dai <zdai@linux.vnet.ibm.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200805030455.123024-4-leobras.c@gmail.com

powerpc/pseries/iommu: Update call to ibm, query-pe-dma-windows

>From LoPAR level 2.8, "ibm,ddw-extensions" index 3 can make the number of
outputs from "ibm,query-pe-dma-windows" go from 5 to 6.

This change of output size is meant to expand the address size of
largest_available_block PE TCE from 32-bit to 64-bit, which ends up
shifting page_size and migration_capable.

This ends up requiring the update of
ddw_query_response->largest_available_block from u32 to u64, and manually
assigning the values from the buffer into this struct, according to
output size.

Also, a routine was created for helping reading the ddw extensions as
suggested by LoPAR: First reading the size of the extension array from
index 0, checking if the property exists, and then returning it's value.

Signed-off-by: Leonardo Bras <leobras.c@gmail.com>
Tested-by: David Dai <zdai@linux.vnet.ibm.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200805030455.123024-3-leobras.c@gmail.com

powerpc/pseries/iommu: Create defines for operations in ibm, ddw-applicable

Create defines to help handling ibm,ddw-applicable values, avoiding
confusion about the index of given operations.

Signed-off-by: Leonardo Bras <leobras.c@gmail.com>
Tested-by: David Dai <zdai@linux.vnet.ibm.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200805030455.123024-2-leobras.c@gmail.com

powerpc: Update documentation of ISA versions for Power10

Update the CPU to ISA Version Mapping document to include Power10 and
ISA v3.1.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
[mpe: Make sure ISA reference is unique]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200827040556.1783-1-jniethe5@gmail.com

powerpc/tools: Remove 90 line limit in checkpatch script

As of commit bdc48fa11e46, scripts/checkpatch.pl now has a default line
length warning of 100 characters.  The powerpc wrapper script was using
a length of 90 instead of 80 in order to make checkpatch less
restrictive, but now it's making it more restrictive instead.

I think it makes sense to just use the default value now.

Signed-off-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200828020542.393022-1-ruscur@russell.cc

selftests/powerpc: Fix prefixes in alignment_handler signal handler

The signal handler in the alignment handler self test has the ability
to jump over the instruction that triggered the signal. It does this
by incrementing the PT_NIP in the user context by 4. If it were a
prefixed instruction this will mean that the suffix is then executed
which is incorrect. Instead check if the major opcode indicates a
prefixed instruction (e.g. it is 1) and if so increment PT_NIP by 8.

If ISA v3.1 is not available treat it as a word instruction even if
the major opcode is 1.

Fixes: 620a6473df36 ("selftests/powerpc: Add prefixed loads/stores to alignment_handler test")
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
[mpe: Fix 32-bit build, rename haveprefixes to prefixes_enabled]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200824131231.14008-1-jniethe5@gmail.com

powerpc/boot: Update Makefile comment for 64bit wrapper

As of commit 147c05168fc8 ("powerpc/boot: Add support for 64bit little
endian wrapper") the comment in the Makefile is misleading. The wrapper
packaging 64bit kernel may built as a 32 or 64 bit elf. Update the
comment to reflect this.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200825035147.3239-1-jniethe5@gmail.com

powerpc/64: Remove unused generic_secondary_thread_init()

The last caller was removed in 2014 in commit fb5a515704d7 ("powerpc:
Remove platforms/wsp and associated pieces").

As Jordan noticed even though there are no callers, the code above in
fsl_secondary_thread_init() falls through into
generic_secondary_thread_init(). So we can remove the _GLOBAL but not
the body of the function.

However because fsl_secondary_thread_init() is inside #ifdef
CONFIG_PPC_BOOK3E, we can never reach the body of
generic_secondary_thread_init() unless CONFIG_PPC_BOOK3E is enabled,
so we can wrap the whole thing in a single #ifdef.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200819015704.1976364-1-mpe@ellerman.id.au

selftests/powerpc: Properly handle failure in switch_endian_test

On older CPUs the switch_endian() syscall doesn't work. Currently that
causes the switch_endian_test to just crash. Instead detect the
failure and properly exit with a failure message.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200819015727.1977134-9-mpe@ellerman.id.au

selftests/powerpc: Don't touch VMX/VSX on older CPUs

If we're running on a CPU without VMX/VSX then don't touch them. This
is fragile, the compiler could spill a VMX/VSX register and break the
test anyway. But in practice it seems to work, ie. the test runs to
completion on a system without VSX with this change.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200819015727.1977134-8-mpe@ellerman.id.au

selftests/powerpc: Skip L3 bank test on older CPUs

This is a test of specific piece of logic in isa207-common.c, which is
only used on Power8 or later. So skip it on older CPUs.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200819015727.1977134-7-mpe@ellerman.id.au

selftests/powerpc: Skip security tests on older CPUs

Both these tests use PMU events that only work on newer CPUs, so skip
them on older CPUs.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200819015727.1977134-6-mpe@ellerman.id.au

selftests/powerpc: Don't run DSCR tests on old systems

The DSCR tests fail on systems that don't have DSCR, so check for the
DSCR in hwcap and skip if it's not present.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200819015727.1977134-5-mpe@ellerman.id.au

selftests/powerpc: Include asm/cputable.h from utils.h

utils.h provides have_hwcap() and have_hwcap2() which check for a
feature bit. Those bits are defined in asm/cputable.h, so include it
in utils.h so users of utils.h don't have to do it manually.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200819015727.1977134-4-mpe@ellerman.id.au

selftests/powerpc: Move set_dscr() into rfi_flush.c

This version of set_dscr() was added for the RFI flush test, and is
fairly specific to it. It also clashes with the version of set_dscr()
in dscr/dscr.h. So move it into the RFI flush test where it's used.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200819015727.1977134-3-mpe@ellerman.id.au

selftests/powerpc: Give the bad_accesses test longer to run

On older systems this test takes longer to run (duh), give it five
minutes which is long enough on a G5 970FX @ 1.6GHz.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200819015727.1977134-2-mpe@ellerman.id.au

selftests/powerpc: Make using_hash_mmu() work on Cell & PowerMac

These platforms don't show the MMU in /proc/cpuinfo, but they always
use hash, so teach using_hash_mmu() that.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200819015727.1977134-1-mpe@ellerman.id.au

selftests/powerpc: Run tm-tmspr test for longer

This test creates some threads, which write to TM SPRs, and then makes
sure the registers maintain the correct values across context switches
and contention with other threads.

But currently the test finishes almost instantaneously, which reduces
the chance of it hitting an interesting condition.

So increase the number of loops, so it runs a bit longer, though still
less than 2s on a Power8.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200813013445.686464-3-mpe@ellerman.id.au

selftests/powerpc: Don't use setaffinity in tm-tmspr

This test tries to set affinity to CPUs that don't exist, especially
if the set of online CPUs doesn't start at 0.

But there's no real reason for it to use setaffinity in the first
place, it's just trying to create lots of threads to cause contention.
So drop the setaffinity entirely.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200813013445.686464-2-mpe@ellerman.id.au

selftests/powerpc: Fix TM tests when CPU 0 is offline

Several of the TM tests fail spuriously if CPU 0 is offline, because
they blindly try to affinitise to CPU 0.

Fix them by picking any online CPU and using that instead.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200813013445.686464-1-mpe@ellerman.id.au

powerpc/pseries/eeh: Fix dumb linebreaks

These annoy me every time I see them. Why are they here? They're not even
needed for 80cols compliance.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200818044557.135497-1-oohall@gmail.com

powerpc/process: Remove unnecessary #ifdef CONFIG_FUNCTION_GRAPH_TRACER

ftrace_graph_ret_addr() is always defined and returns 'ip' when
CONFIG_FUNCTION GRAPH_TRACER is not set.

So the #ifdef is not needed, remove it.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/9d11143d4e27ba8274369a926968756917584868.1597643153.git.christophe.leroy@csgroup.eu

powerpc/uaccess: Add pre-update addressing to __get_user_asm() and __put_user_asm()

Enable pre-update addressing mode in __get_user_asm() and __put_user_asm()

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/13041c7df39e89ddf574ea0cdc6dedfdd9734140.1597235091.git.christophe.leroy@csgroup.eu

cpuidle: pseries: Fix CEDE latency conversion from tb to us

Commit d947fb4c965c ("cpuidle: pseries: Fixup exit latency for
CEDE(0)") sets the exit latency of CEDE(0) based on the latency values
of the Extended CEDE states advertised by the platform. The values
advertised by the platform are in timebase ticks. However the cpuidle
framework requires the latency values in microseconds.

If the tb-ticks value advertised by the platform correspond to a value
smaller than 1us, during the conversion from tb-ticks to microseconds,
in the current code, the result becomes zero. This is incorrect as it
puts a CEDE state on par with the snooze state.

This patch fixes this by rounding up the result obtained while
converting the latency value from tb-ticks to microseconds. It also
prints a warning in case we discover an extended-cede state with
wakeup latency to be 0. In such a case, ensure that CEDE(0) has a
non-zero wakeup latency.

Fixes: d947fb4c965c ("cpuidle: pseries: Fixup exit latency for CEDE(0)")
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Reviewed-by: Vaidyanathan Srinivasan <svaidy@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1599125247-28488-1-git-send-email-ego@linux.vnet.ibm.com

powerpc/dma: Fix dma_map_ops::get_required_mask

There are 2 problems with it:
  1. "<" vs expected "<<"
  2. the shift number is an IOMMU page number mask, not an address
  mask as the IOMMU page shift is missing.

This did not hit us before f1565c24b596 ("powerpc: use the generic
dma_ops_bypass mode") because we had additional code to handle bypass
mask so this chunk (almost?) never executed.However there were
reports that aacraid does not work with "iommu=nobypass".

After f1565c24b596, aacraid (and probably others which call
dma_get_required_mask() before setting the mask) was unable to enable
64bit DMA and fall back to using IOMMU which was known not to work,
one of the problems is double free of an IOMMU page.

This fixes DMA for aacraid, both with and without "iommu=nobypass" in
the kernel command line. Verified with "stress-ng -d 4".

Fixes: 6a5c7be5e484 ("powerpc: Override dma_get_required_mask by platform hook and ops")
Cc: stable@vger.kernel.org # v3.2+
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200908015106.79661-1-aik@ozlabs.ru

Revert "powerpc/build: vdso linker warning for orphan sections"

This reverts commit f2af201002a8bc22500c04cc474ea480bf361351.

It added a usage of cc-ldoption, but cc-ldoption was removed in commit
055efab3120b ("kbuild: drop support for cc-ldoption").

Reported-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/mm: Remove DEBUG_VM_PGTABLE support on powerpc

The test is broken w.r.t page table update rules and results in kernel
crash as below. Disable the support until we get the tests updated.

[   21.083519] kernel BUG at arch/powerpc/mm/pgtable.c:304!
cpu 0x0: Vector: 700 (Program Check) at [c000000c6d1e76c0]
    pc: c00000000009a5ec: assert_pte_locked+0x14c/0x380
    lr: c0000000005eeeec: pte_update+0x11c/0x190
    sp: c000000c6d1e7950
   msr: 8000000002029033
  current = 0xc000000c6d172c80
  paca    = 0xc000000003ba0000   irqmask: 0x03   irq_happened: 0x01
    pid   = 1, comm = swapper/0
kernel BUG at arch/powerpc/mm/pgtable.c:304!
[link register   ] c0000000005eeeec pte_update+0x11c/0x190
[c000000c6d1e7950] 0000000000000001 (unreliable)
[c000000c6d1e79b0] c0000000005eee14 pte_update+0x44/0x190
[c000000c6d1e7a10] c000000001a2ca9c pte_advanced_tests+0x160/0x3d8
[c000000c6d1e7ab0] c000000001a2d4fc debug_vm_pgtable+0x7e8/0x1338
[c000000c6d1e7ba0] c0000000000116ec do_one_initcall+0xac/0x5f0
[c000000c6d1e7c80] c0000000019e4fac kernel_init_freeable+0x4dc/0x5a4
[c000000c6d1e7db0] c000000000012474 kernel_init+0x24/0x160
[c000000c6d1e7e20] c00000000000cbd0 ret_from_kernel_thread+0x5c/0x6c

With DEBUG_VM disabled

[   20.530152] BUG: Kernel NULL pointer dereference on read at 0x00000000
[   20.530183] Faulting instruction address: 0xc0000000000df330
cpu 0x33: Vector: 380 (Data SLB Access) at [c000000c6d19f700]
    pc: c0000000000df330: memset+0x68/0x104
    lr: c00000000009f6d8: hash__pmdp_huge_get_and_clear+0xe8/0x1b0
    sp: c000000c6d19f990
   msr: 8000000002009033
   dar: 0
  current = 0xc000000c6d177480
  paca    = 0xc00000001ec4f400   irqmask: 0x03   irq_happened: 0x01
    pid   = 1, comm = swapper/0
[link register   ] c00000000009f6d8 hash__pmdp_huge_get_and_clear+0xe8/0x1b0
[c000000c6d19f990] c00000000009f748 hash__pmdp_huge_get_and_clear+0x158/0x1b0 (unreliable)
[c000000c6d19fa10] c0000000019ebf30 pmd_advanced_tests+0x1f0/0x378
[c000000c6d19fab0] c0000000019ed088 debug_vm_pgtable+0x79c/0x1244
[c000000c6d19fba0] c0000000000116ec do_one_initcall+0xac/0x5f0
[c000000c6d19fc80] c0000000019a4fac kernel_init_freeable+0x4dc/0x5a4
[c000000c6d19fdb0] c000000000012474 kernel_init+0x24/0x160
[c000000c6d19fe20] c00000000000cbd0 ret_from_kernel_thread+0x5c/0x6c
33:mon>

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200902040122.136414-1-aneesh.kumar@linux.ibm.com

powerpc/uaccess: Use flexible addressing with __put_user()/__get_user()

At the time being, __put_user()/__get_user() and friends only use
D-form addressing, with 0 offset. Ex:

lwz reg1, 0(reg2)

Give the compiler the opportunity to use other adressing modes
whenever possible, to get more optimised code.

Hereunder is a small exemple:

struct test {
u32 item1;
u16 item2;
u8 item3;
u64 item4;
};

int set_test_user(struct test __user *from, struct test __user *to)
{
int err;
u32 item1;
u16 item2;
u8 item3;
u64 item4;

err = __get_user(item1, &from->item1);
err |= __get_user(item2, &from->item2);
err |= __get_user(item3, &from->item3);
err |= __get_user(item4, &from->item4);

err |= __put_user(item1, &to->item1);
err |= __put_user(item2, &to->item2);
err |= __put_user(item3, &to->item3);
err |= __put_user(item4, &to->item4);

return err;
}

Before the patch:

00000df0 <set_test_user>:
 df0: 94 21 ff f0  stwu    r1,-16(r1)
 df4: 39 40 00 00  li      r10,0
 df8: 93 c1 00 08  stw     r30,8(r1)
 dfc: 93 e1 00 0c  stw     r31,12(r1)
 e00: 7d 49 53 78  mr      r9,r10
 e04: 80 a3 00 00  lwz     r5,0(r3)
 e08: 38 e3 00 04  addi    r7,r3,4
 e0c: 7d 46 53 78  mr      r6,r10
 e10: a0 e7 00 00  lhz     r7,0(r7)
 e14: 7d 29 33 78  or      r9,r9,r6
 e18: 39 03 00 06  addi    r8,r3,6
 e1c: 7d 46 53 78  mr      r6,r10
 e20: 89 08 00 00  lbz     r8,0(r8)
 e24: 7d 29 33 78  or      r9,r9,r6
 e28: 38 63 00 08  addi    r3,r3,8
 e2c: 7d 46 53 78  mr      r6,r10
 e30: 83 c3 00 00  lwz     r30,0(r3)
 e34: 83 e3 00 04  lwz     r31,4(r3)
 e38: 7d 29 33 78  or      r9,r9,r6
 e3c: 7d 43 53 78  mr      r3,r10
 e40: 90 a4 00 00  stw     r5,0(r4)
 e44: 7d 29 1b 78  or      r9,r9,r3
 e48: 38 c4 00 04  addi    r6,r4,4
 e4c: 7d 43 53 78  mr      r3,r10
 e50: b0 e6 00 00  sth     r7,0(r6)
 e54: 7d 29 1b 78  or      r9,r9,r3
 e58: 38 e4 00 06  addi    r7,r4,6
 e5c: 7d 43 53 78  mr      r3,r10
 e60: 99 07 00 00  stb     r8,0(r7)
 e64: 7d 23 1b 78  or      r3,r9,r3
 e68: 38 84 00 08  addi    r4,r4,8
 e6c: 93 c4 00 00  stw     r30,0(r4)
 e70: 93 e4 00 04  stw     r31,4(r4)
 e74: 7c 63 53 78  or      r3,r3,r10
 e78: 83 c1 00 08  lwz     r30,8(r1)
 e7c: 83 e1 00 0c  lwz     r31,12(r1)
 e80: 38 21 00 10  addi    r1,r1,16
 e84: 4e 80 00 20  blr

After the patch:

00000dbc <set_test_user>:
 dbc: 39 40 00 00  li      r10,0
 dc0: 7d 49 53 78  mr      r9,r10
 dc4: 80 03 00 00  lwz     r0,0(r3)
 dc8: 7d 48 53 78  mr      r8,r10
 dcc: a1 63 00 04  lhz     r11,4(r3)
 dd0: 7d 29 43 78  or      r9,r9,r8
 dd4: 7d 48 53 78  mr      r8,r10
 dd8: 88 a3 00 06  lbz     r5,6(r3)
 ddc: 7d 29 43 78  or      r9,r9,r8
 de0: 7d 48 53 78  mr      r8,r10
 de4: 80 c3 00 08  lwz     r6,8(r3)
 de8: 80 e3 00 0c  lwz     r7,12(r3)
 dec: 7d 29 43 78  or      r9,r9,r8
 df0: 7d 43 53 78  mr      r3,r10
 df4: 90 04 00 00  stw     r0,0(r4)
 df8: 7d 29 1b 78  or      r9,r9,r3
 dfc: 7d 43 53 78  mr      r3,r10
 e00: b1 64 00 04  sth     r11,4(r4)
 e04: 7d 29 1b 78  or      r9,r9,r3
 e08: 7d 43 53 78  mr      r3,r10
 e0c: 98 a4 00 06  stb     r5,6(r4)
 e10: 7d 23 1b 78  or      r3,r9,r3
 e14: 90 c4 00 08  stw     r6,8(r4)
 e18: 90 e4 00 0c  stw     r7,12(r4)
 e1c: 7c 63 53 78  or      r3,r3,r10
 e20: 4e 80 00 20  blr

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c27bc4e598daf3bbb225de7a1f5c52121cf1e279.1597235091.git.christophe.leroy@csgroup.eu

powerpc: Remove flush_instruction_cache() on 8xx

flush_instruction_cache() is never used on 8xx, remove it.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/245cabd8f291facac8c8c5fd370e361a69e02860.1597384145.git.christophe.leroy@csgroup.eu

powerpc: unrel_branch_check.sh: enable the use of llvm-objdump v9, 10 or 11

Currently, using llvm-objtool, this script just silently succeeds without
actually do the intended checking.  So this updates it to work properly.

Firstly, llvm-objdump does not add target symbol names to the end
of branches in its asm output, so we have to drop the branch to
__start_initialization_multiplatform using its address.

Secondly, v9 and 10 specify branch targets as .+<offset>, so we convert
those to actual addresses.

Thirdly, v10 and 11 error out on a vmlinux if given the -R option
complaining that it is "not a dynamic object".  The -R does not make
any difference to the asm output, so remove it.

Lastly, v11 produces asm that is very similar to Gnu objtool (at least
as far as branches are concerned), so no further changes are necessary
to make it work.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200812081036.7969-3-sfr@canb.auug.org.au

powerpc: unrel_branch_check.sh: use nm to find symbol value

This is considerably faster then parsing the objdump asm output.  It will
also make the enabling of llvm-objdump a little easier.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200812081036.7969-2-sfr@canb.auug.org.au

powerpc: unrel_branch_check.sh: exit silently for early errors

If we can't find the address of __end_interrupts, then we still exit
successfully as that is the current behaviour.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200811140435.20957-8-sfr@canb.auug.org.au

powerpc: unrel_branch_check.sh: fix up the file header

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200811140435.20957-7-sfr@canb.auug.org.au

powerpc: unrel_branch_check.sh: simplify and tidy up the final loop

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200811140435.20957-6-sfr@canb.auug.org.au

powerpc: unrel_branch_check.sh: convert grep | sed | awk to just sed

Also start using sed -E and make all the separate expressions into a
single one with comments.  Pull the stripping of condition registers
back into the sed command.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200811140435.20957-5-sfr@canb.auug.org.au

powerpc: unrel_branch_check.sh: simplify objdump's asm output

We don't use the raw hex instruction dump, so elide it and adjust the
following expressions.

Also use \s instead of [[:space:]] everywhere.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200811140435.20957-4-sfr@canb.auug.org.au

powerpc: unrel_branch_check.sh: simplify and combine some executions

Also some minor style changes.

There should still be no change in behaviour.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200811140435.20957-3-sfr@canb.auug.org.au

powerpc: unrel_branch_check.sh: fix shellcheck complaints

No functional change

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200811140435.20957-2-sfr@canb.auug.org.au

pseries/drmem: don't cache node id in drmem_lmb struct

At memory hot-remove time we can retrieve an LMB's nid from its
corresponding memory_block.  There is no need to store the nid
in multiple locations.

Note that lmb_to_memblock() uses find_memory_block() to get the
corresponding memory_block.  As find_memory_block() runs in sub-linear
time this approach is negligibly slower than what we do at present.

In exchange for this lookup at hot-remove time we no longer need to
call memory_add_physaddr_to_nid() during drmem_init() for each LMB.
On powerpc, memory_add_physaddr_to_nid() is a linear search, so this
spares us an O(n^2) initialization during boot.

On systems with many LMBs that initialization overhead is palpable and
disruptive.  For example, on a box with 249854 LMBs we're seeing
drmem_init() take upwards of 30 seconds to complete:

[   53.721639] drmem: initializing drmem v2
[   80.604346] watchdog: BUG: soft lockup - CPU#65 stuck for 23s! [swapper/0:1]
[   80.604377] Modules linked in:
[   80.604389] CPU: 65 PID: 1 Comm: swapper/0 Not tainted 5.6.0-rc2+ #4
[   80.604397] NIP:  c0000000000a4980 LR: c0000000000a4940 CTR: 0000000000000000
[   80.604407] REGS: c0002dbff8493830 TRAP: 0901   Not tainted  (5.6.0-rc2+)
[   80.604412] MSR:  8000000002009033 <SF,VEC,EE,ME,IR,DR,RI,LE>  CR: 44000248  XER: 0000000d
[   80.604431] CFAR: c0000000000a4a38 IRQMASK: 0
[   80.604431] GPR00: c0000000000a4940 c0002dbff8493ac0 c000000001904400 c0003cfffffede30
[   80.604431] GPR04: 0000000000000000 c000000000f4095a 000000000000002f 0000000010000000
[   80.604431] GPR08: c0000bf7ecdb7fb8 c0000bf7ecc2d3c8 0000000000000008 c00c0002fdfb2001
[   80.604431] GPR12: 0000000000000000 c00000001e8ec200
[   80.604477] NIP [c0000000000a4980] hot_add_scn_to_nid+0xa0/0x3e0
[   80.604486] LR [c0000000000a4940] hot_add_scn_to_nid+0x60/0x3e0
[   80.604492] Call Trace:
[   80.604498] [c0002dbff8493ac0] [c0000000000a4940] hot_add_scn_to_nid+0x60/0x3e0 (unreliable)
[   80.604509] [c0002dbff8493b20] [c000000000087c10] memory_add_physaddr_to_nid+0x20/0x60
[   80.604521] [c0002dbff8493b40] [c0000000010d4880] drmem_init+0x25c/0x2f0
[   80.604530] [c0002dbff8493c10] [c000000000010154] do_one_initcall+0x64/0x2c0
[   80.604540] [c0002dbff8493ce0] [c0000000010c4aa0] kernel_init_freeable+0x2d8/0x3a0
[   80.604550] [c0002dbff8493db0] [c000000000010824] kernel_init+0x2c/0x148
[   80.604560] [c0002dbff8493e20] [c00000000000b648] ret_from_kernel_thread+0x5c/0x74
[   80.604567] Instruction dump:
[   80.604574] 392918e8 e9490000 e90a000a e92a0000 80ea000c 1d080018 3908ffe8 7d094214
[   80.604586] 7fa94040 419d00dc e9490010 714a0088 <2faa0008> 409e00ac e9490000 7fbe5040
[   89.047390] drmem: 249854 LMB(s)

With a patched kernel on the same machine we're no longer seeing the
soft lockup.  drmem_init() now completes in negligible time, even when
the LMB count is large.

Fixes: b2d3b5ee66f2 ("powerpc/pseries: Track LMB nid instead of using device tree")
Signed-off-by: Scott Cheloha <cheloha@linux.ibm.com>
Reviewed-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200811015115.63677-1-cheloha@linux.ibm.com

powerpc: Rewrite FSL_BOOKE flush_cache_instruction() in C

Nothing prevents flush_cache_instruction() from being writen in C.

Do it to improve readability and maintainability.

This function is only use by low level callers, it is not
intended to be used by module. Don't export it.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/f989eff8296800c427622c0985384148404e4f0b.1597384512.git.christophe.leroy@csgroup.eu

powerpc: Rewrite 4xx flush_cache_instruction() in C

Nothing prevents flush_cache_instruction() from being writen in C.

Do it to improve readability and maintainability.

This function is very small and isn't called from assembly,
make it static inline in asm/cacheflush.h

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/93d93fc69b4b3ad3ceba2fc0756333c0c0245bb7.1597384512.git.christophe.leroy@csgroup.eu

powerpc: Move flush_instruction_cache() prototype in asm/cacheflush.h

flush_instruction_cache() belongs to the cache flushing function
family.

Move its prototype in asm/cacheflush.h

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/993445b5227e8ca2f0e38bcc9ea3dfea6e865920.1597384512.git.christophe.leroy@csgroup.eu

powerpc: Remove flush_instruction_cache for book3s/32

The only callers of flush_instruction_cache() are:

arch/powerpc/kernel/swsusp_booke.S: bl flush_instruction_cache
arch/powerpc/mm/nohash/40x.c: flush_instruction_cache();
arch/powerpc/mm/nohash/44x.c: flush_instruction_cache();
arch/powerpc/mm/nohash/fsl_booke.c: flush_instruction_cache();
arch/powerpc/platforms/44x/machine_check.c: flush_instruction_cache();
arch/powerpc/platforms/44x/machine_check.c: flush_instruction_cache();

This function is not used by book3s/32, drop it.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/50098f49877cea0f46730a9df82dcabf84160e4b.1597384512.git.christophe.leroy@csgroup.eu

powerpc/pseries: explicitly reschedule during drmem_lmb list traversal

The drmem lmb list can have hundreds of thousands of entries, and
unfortunately lookups take the form of linear searches. As long as
this is the case, traversals have the potential to monopolize the CPU
and provoke lockup reports, workqueue stalls, and the like unless
they explicitly yield.

Rather than placing cond_resched() calls within various
for_each_drmem_lmb() loop blocks in the code, put it in the iteration
expression of the loop macro itself so users can't omit it.

Introduce a drmem_lmb_next() iteration helper function which calls
cond_resched() at a regular interval during array traversal. Each
iteration of the loop in DLPAR code paths can involve around ten RTAS
calls which can each take up to 250us, so this ensures the check is
performed at worst every few milliseconds.

Fixes: 6c6ea53725b3 ("powerpc/mm: Separate ibm, dynamic-memory data from DT format")
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200813151131.2070161-1-nathanl@linux.ibm.com

powerpc: Drop _nmask_and_or_msr()

_nmask_and_or_msr() is only used at two places to set MSR_IP.

The SYNC is unnecessary as the users are not PowerPC 601.

Can be easily writen in C.

Do it, and drop _nmask_and_or_msr()

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c2d2b8dfb8dd677026b26dffc8d31070c38a6b89.1597388079.git.christophe.leroy@csgroup.eu

powerpc: Use simple i2c probe function

The i2c probe functions here don't use the id information provided in
their second argument, so the single-parameter i2c probe
function ("probe_new") can be used instead.

This avoids scanning the identifier tables during probes.

Signed-off-by: Stephen Kitt <steve@sk2.org>
Acked-by: Wolfram Sang <wsa@kernel.org>
Reviewed-by: Luca Ceresoli <luca@lucaceresoli.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200807152713.381588-1-steve@sk2.org

powerpc/pseries: new lparcfg key/value pair: partition_affinity_score

The H_GetPerformanceCounterInfo (GPCI) PHYP hypercall has a subcall,
Affinity_Domain_Info_By_Partition, which returns, among other things,
a "partition affinity score" for a given LPAR.  This score, a value on
[0-100], represents the processor-memory affinity for the LPAR in
question.  A score of 0 indicates the worst possible affinity while a
score of 100 indicates perfect affinity.  The score can be used to
reason about performance.

This patch adds the score for the local LPAR to the lparcfg procfile
under a new 'partition_affinity_score' key.

Signed-off-by: Scott Cheloha <cheloha@linux.ibm.com>
Reviewed-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Acked-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200727184605.2945095-2-cheloha@linux.ibm.com

powerpc/perf: consolidate GPCI hcall structs into asm/hvcall.h

The H_GetPerformanceCounterInfo (GPCI) hypercall input/output structs are
useful to modules outside of perf/, so move them into asm/hvcall.h to live
alongside the other powerpc hypercall structs.

Leave the perf-specific GPCI stuff in perf/hv-gpci.h.

Signed-off-by: Scott Cheloha <cheloha@linux.ibm.com>
Acked-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200727184605.2945095-1-cheloha@linux.ibm.com

powerpc: drop hard_reset_now() and poweroff_now() declaration

Those function have never existed. Drop their declaration.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/edcdd72a36495d25213c0256c8022367458e0d19.1596716418.git.christophe.leroy@csgroup.eu

powerpc/fpu: Drop cvt_fd() and cvt_df()

Those two functions have been unused since commit identified below.
Drop them.

Fixes: 31bfdb036f12 ("powerpc: Use instruction emulation infrastructure to handle alignment faults")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/d5641ada199b8dd2af16ad00a66084cf974f2704.1596716418.git.christophe.leroy@csgroup.eu

powerpc/irq: Drop forward declaration of struct irqaction

Since the commit identified below, the forward declaration of
struct irqaction is useless. Drop it.

Fixes: b709c0832824 ("ppc64: move stack switching up in interrupt processing")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/e0bcdabac45fcd26c02d7df273bd4a5827c6033d.1596716375.git.christophe.leroy@csgroup.eu

powerpc/hwirq: Remove stale forward irq_chip declaration

Since commit identified below, the forward declaration of
struct irq_chip is useless (was struct hw_interrupt_type at that time)

Remove it, together with the associated comment.

Fixes: c0ad90a32fb6 ("[PATCH] genirq: add ->retrigger() irq op to consolidate hw_irq_resend()")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/fbe58d27cf128d5fe581e4510ded8701858f268e.1596716328.git.christophe.leroy@csgroup.eu

macintosh: windfarm: remove detatch debug containing spelling mistakes

There are spelling mistakes in two debug messages. As recommended
by Wolfram Sang, these can be removed as there is plenty of debug
in the driver core.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Wolfram Sang <wsa@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200806102901.44988-1-colin.king@canonical.com

powerpc/32s: Fix assembler warning about r0

The assembler says:
  arch/powerpc/kernel/head_32.S:1095: Warning: invalid register expression

It's objecting to the use of r0 as the RA argument. That's because
when RA = 0 the literal value 0 is used, rather than the content of
r0, making the use of r0 in the source potentially confusing.

Fix it to use a literal 0, the generated code is identical.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/2b69ac8e1cddff6f808fc7415907179eab4aae9e.1596693679.git.christophe.leroy@csgroup.eu

selftests/powerpc: Skip PROT_SAO test in guests/LPARS

In commit 9b725a90a8f1 ("powerpc/64s: Disallow PROT_SAO in LPARs by
default") PROT_SAO was disabled in guests/LPARs by default. So skip
the test if we are running in a guest to avoid a spurious failure.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200901124653.523182-1-mpe@ellerman.id.au

powerpc/book3s64/radix: Fix boot failure with large amount of guest memory

If the hypervisor doesn't support hugepages, the kernel ends up allocating a large
number of page table pages. The early page table allocation was wrongly
setting the max memblock limit to ppc64_rma_size with radix translation
which resulted in boot failure as shown below.

Kernel panic - not syncing:
early_alloc_pgtable: Failed to allocate 16777216 bytes align=0x1000000 nid=-1 from=0x0000000000000000 max_addr=0xffffffffffffffff
 CPU: 0 PID: 0 Comm: swapper Not tainted 5.8.0-24.9-default+ #2
 Call Trace:
 [c0000000016f3d00] [c0000000007c6470] dump_stack+0xc4/0x114 (unreliable)
 [c0000000016f3d40] [c00000000014c78c] panic+0x164/0x418
 [c0000000016f3dd0] [c000000000098890] early_alloc_pgtable+0xe0/0xec
 [c0000000016f3e60] [c0000000010a5440] radix__early_init_mmu+0x360/0x4b4
 [c0000000016f3ef0] [c000000001099bac] early_init_mmu+0x1c/0x3c
 [c0000000016f3f10] [c00000000109a320] early_setup+0x134/0x170

This was because the kernel was checking for the radix feature before we enable the
feature via mmu_features. This resulted in the kernel using hash restrictions on
radix.

Rework the early init code such that the kernel boot with memblock restrictions
as imposed by hash. At that point, the kernel still hasn't finalized the
translation the kernel will end up using.

We have three different ways of detecting radix.

1. dt_cpu_ftrs_scan -> used only in case of PowerNV
2. ibm,pa-features -> Used when we don't use cpu_dt_ftr_scan
3. CAS -> Where we negotiate with hypervisor about the supported translation.

We look at 1 or 2 early in the boot and after that, we look at the CAS vector to
finalize the translation the kernel will use. We also support a kernel command
line option (disable_radix) to switch to hash.

Update the memblock limit after mmu_early_init_devtree() if the kernel is going
to use radix translation. This forces some of the memblock allocations we do before
mmu_early_init_devtree() to be within the RMA limit.

Fixes: 2bfd65e45e87 ("powerpc/mm/radix: Add radix callbacks for early init routines")
Reported-by: Shirisha Ganta <shiganta@in.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200828100852.426575-1-aneesh.kumar@linux.ibm.com

powerpc/32s: Disable VMAP stack which CONFIG_ADB_PMU

low_sleep_handler() can't restore the context from virtual
stack because the stack can hardly be accessed with MMU OFF.

For now, disable VMAP stack when CONFIG_ADB_PMU is selected.

Fixes: cd08f109e262 ("powerpc/32s: Enable CONFIG_VMAP_STACK")
Cc: stable@vger.kernel.org # v5.6+
Reported-by: Giuseppe Sacco <giuseppe@sguazz.it>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/ec96c15bfa1a7415ab604ee1c98cd45779c08be0.1598553015.git.christophe.leroy@csgroup.eu

Revert "powerpc/powernv/idle: Replace CPU feature check with PVR check"

cpuidle stop state implementation has minor optimizations for P10
where hardware preserves more SPR registers compared to P9. The
current P9 driver works for P10, although does few extra
save-restores. P9 driver can provide the required power management
features like SMT thread folding and core level power savings on a P10
platform.

Until the P10 stop driver is available, revert the commit which allows
for only P9 systems to utilize cpuidle and blocks all idle stop states
for P10. CPU idle states are enabled and tested on the P10 platform
with this fix.

This reverts commit 8747bf36f312356f8a295a0c39ff092d65ce75ae.

Fixes: 8747bf36f312 ("powerpc/powernv/idle: Replace CPU feature check with PVR check")
Signed-off-by: Pratik Rajesh Sampat <psampat@linux.ibm.com>
Reviewed-by: Vaidyanathan Srinivasan <svaidy@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200826082918.89306-1-psampat@linux.ibm.com

powerpc/perf: Fix reading of MSR[HV/PR] bits in trace-imc

IMC trace-mode uses MSR[HV/PR] bits to set the cpumode for the
instruction pointer captured in each sample. The bits are fetched from
the third double word of the trace record. Reading third double word
from IMC trace record should use be64_to_cpu() along with READ_ONCE
inorder to fetch correct MSR[HV/PR] bits. Patch addresses this change.

Currently we are using PERF_RECORD_MISC_HYPERVISOR as cpumode if MSR
HV is 1 and PR is 0 which means the address is from host counter. But
using PERF_RECORD_MISC_HYPERVISOR for host counter data will fail to
resolve the address -> symbol during "perf report" because perf tools
side uses PERF_RECORD_MISC_KERNEL to represent the host counter data.
Therefore, fix the trace imc sample data to use
PERF_RECORD_MISC_KERNEL as cpumode for host kernel information.

Fixes: 77ca3951cc37 ("powerpc/perf: Add kernel support for new MSR[HV PR] bits in trace-imc")
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1598424029-1662-1-git-send-email-atrajeev@linux.vnet.ibm.com

powerpc/perf: Fix crashes with generic_compat_pmu & BHRB

The bhrb_filter_map ("The Branch History Rolling Buffer") callback is
only defined in raw CPUs' power_pmu structs. The "architected" CPUs
use generic_compat_pmu, which does not have this callback, and crashes
occur if a user tries to enable branch stack for an event.

This add a NULL pointer check for bhrb_filter_map() which behaves as
if the callback returned an error.

This does not add the same check for config_bhrb() as the only caller
checks for cpuhw->bhrb_users which remains zero if bhrb_filter_map==0.

Fixes: be80e758d0c2 ("powerpc/perf: Add generic compat mode pmu driver")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200602025612.62707-1-aik@ozlabs.ru

powerpc/64s: Fix crash in load_fp_state() due to fpexc_mode

The recent commit 01eb01877f33 ("powerpc/64s: Fix restore_math
unnecessarily changing MSR") changed some of the handling of floating
point/vector restore.

In particular it caused current->thread.fpexc_mode to be copied into
the current MSR (via msr_check_and_set()), rather than just into
regs->msr (which is moved into MSR on return to userspace).

This can lead to a crash in the kernel if we take a floating point
exception when restoring FPSCR:

  Oops: Exception in kernel mode, sig: 8 [#1]
  LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA PowerNV
  Modules linked in:
  CPU: 3 PID: 101213 Comm: ld64.so.2 Not tainted 5.9.0-rc1-00098-g18445bf405cb-dirty #9
  NIP:  c00000000000fbb4 LR: c00000000001a7ac CTR: c000000000183570
  REGS: c0000016b7cfb3b0 TRAP: 0700   Not tainted  (5.9.0-rc1-00098-g18445bf405cb-dirty)
  MSR:  900000000290b933 <SF,HV,VEC,VSX,EE,FP,ME,IR,DR,RI,LE>  CR: 44002444  XER: 00000000
  CFAR: c00000000001a7a8 IRQMASK: 1
  GPR00: c00000000001ae40 c0000016b7cfb640 c0000000011b7f00 c000001542a0f740
  GPR04: c000001542a0f720 c000001542a0eb00 0000000000000900 c000001542a0eb00
  GPR08: 000000000000000a 0000000000002000 9000000000009033 0000000000000000
  GPR12: 0000000000004000 c0000017ffffd900 0000000000000001 c000000000df5a58
  GPR16: c000000000e19c18 c0000000010e1123 0000000000000001 c000000000e1a638
  GPR20: 0000000000000000 c0000000044b1d00 0000000000000000 c000001542a0f2a0
  GPR24: 00000016c7fe0000 c000001542a0f720 c000000001c93da0 c000000000fe5f28
  GPR28: c000001542a0f720 0000000000800000 c0000016b7cfbe90 0000000002802900
  NIP load_fp_state+0x4/0x214
  LR  restore_math+0x17c/0x1f0
  Call Trace:
    0xc0000016b7cfb680 (unreliable)
    __switch_to+0x330/0x460
    __schedule+0x318/0x920
    schedule+0x74/0x140
    schedule_timeout+0x318/0x3f0
    wait_for_completion+0xc8/0x210
    call_usermodehelper_exec+0x234/0x280
    do_coredump+0xedc/0x13c0
    get_signal+0x1d4/0xbe0
    do_notify_resume+0x1a0/0x490
    interrupt_exit_user_prepare+0x1c4/0x230
    interrupt_return+0x14/0x1c0
  Instruction dump:
  ebe10168 e88101a0 7c8ff120 382101e0 e8010010 7c0803a6 4e800020 790605c4
  782905c4 7c0008a8 7c0008a8 c8030200 <fffe058e> 48000088 c8030000 c8230010

Fix it by only loading the fpexc_mode value into regs->msr.

Also add a comment to explain that although VSX is subject to the
value of fpexc_mode, we don't have to handle that separately because
we only allow VSX to be enabled if FP is also enabled.

Fixes: 01eb01877f33 ("powerpc/64s: Fix restore_math unnecessarily changing MSR")
Reported-by: Milton Miller <miltonm@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Link: https://lore.kernel.org/r/20200825093424.3967813-1-mpe@ellerman.id.au

powerpc/64s: scv entry should set PPR

Kernel entry sets PPR to HMT_MEDIUM by convention. The scv entry
path missed this.

Fixes: 7fa95f9adaee ("powerpc/64s: system call support for scv/rfscv instructions")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200825075309.224184-1-npiggin@gmail.com

Documentation/powerpc: fix malformed table in syscall64-abi

Fix malformed table warning in powerpc/syscall64-abi.rst by making
two tables and moving the headings.

Documentation/powerpc/syscall64-abi.rst:53: WARNING: Malformed table.
Text in column margin in table line 2.

  =========== ============= ========================================
  --- For the sc instruction, differences with the ELF ABI ---
  r0          Volatile      (System call number.)
  r3          Volatile      (Parameter 1, and return value.)
  r4-r8       Volatile      (Parameters 2-6.)
  cr0         Volatile      (cr0.SO is the return error condition.)
  cr1, cr5-7  Nonvolatile
  lr          Nonvolatile

  --- For the scv 0 instruction, differences with the ELF ABI ---
  r0          Volatile      (System call number.)
  r3          Volatile      (Parameter 1, and return value.)
  r4-r8       Volatile      (Parameters 2-6.)
  =========== ============= ========================================

Fixes: 7fa95f9adaee ("powerpc/64s: system call support for scv/rfscv instructions")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/e06de4d3-a36f-2745-9775-467e125436cc@infradead.org

video: fbdev: controlfb: Fix build for COMPILE_TEST=y && PPC_PMAC=n

The build is currently broken, if COMPILE_TEST=y and PPC_PMAC=n:

  linux/drivers/video/fbdev/controlfb.c: In function ‘control_set_hardware’:
  linux/drivers/video/fbdev/controlfb.c:276:2: error: implicit declaration of function ‘btext_update_display’
    276 |  btext_update_display(p->frame_buffer_phys + CTRLFB_OFF,
        |  ^~~~~~~~~~~~~~~~~~~~

Fix it by including btext.h whenever CONFIG_BOOTX_TEXT is enabled.

Fixes: a07a63b0e24d ("video: fbdev: controlfb: add COMPILE_TEST support")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://lore.kernel.org/r/20200821104910.3363818-1-mpe@ellerman.id.au

powerpc/nx: Don't pack struct coprocessor_request_block

Building with W=1 results in the following warning:

In file included from arch/powerpc/platforms/powernv/vas-fault.c:16:
./arch/powerpc/include/asm/icswx.h:159:1: error: alignment 1 of ‘struct
coprocessor_request_block’ is less than 16 [-Werror=packed-not-aligned]
  159 | } __packed;
      | ^
./arch/powerpc/include/asm/icswx.h:159:1: error: alignment 1 of ‘struct
coprocessor_request_block’ is less than 16 [-Werror=packed-not-aligned]
./arch/powerpc/include/asm/icswx.h:159:1: error: alignment 1 of ‘struct
coprocessor_request_block’ is less than 16 [-Werror=packed-not-aligned]
./arch/powerpc/include/asm/icswx.h:159:1: error: alignment 1 of ‘struct
coprocessor_request_block’ is less than 16 [-Werror=packed-not-aligned]
cc1: all warnings being treated as errors

This happens because coprocessor_request_block includes several
sub-structures with an alignment specified using the __aligned(XX)
attribute. The problem comes from coprocessor_request_block having the
__packed attribute. Packing the structure causes the preferred alignment of
the nested structures to be ignored and we get the warnings as a result.

This isn't a problem in practice since the struct is defined with explicit
padding in the form of reserved fields, but we'd like to get rid of the
spurious warnings. The simplest solution is to remove the packed attribute
and use a BUILD_BUG_ON() to ensure the struct is the correct (expected by
HW) size compile time.

Also add a __aligned(128) to the request block structure since Book4 for P8
suggests the HW requires it to be aligned to a 128 byte boundary. There's a
similar requirement for P9 since the COPY and PASTE instructions used to
invoke VAS/NX accelerators operates on a cache line boundary.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200804005410.146094-7-oohall@gmail.com

powerpc/powernv: Fix spurious kerneldoc warnings in opal-prd.c

Comments opening with /** are parsed by kerneldoc and this causes the
following warning to be printed:

arch/powerpc/platforms/powernv/opal-prd.c:31: warning: cannot understand
function prototype: 'struct opal_prd_msg_queue_item '

opal_prd_mesg_queue_item is an internal data structure so there's no real
need for it to be documented at all. Fix up the comment to squash the
warning.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200804005410.146094-5-oohall@gmail.com

powerpc/powernv: Staticify functions without prototypes

There's a few scattered in the powernv platform.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200804005410.146094-4-oohall@gmail.com

powerpc/powernv: Include asm/powernv.h from the local powernv.h

The asm/powernv.h header provides prototypes for functions which need to be
called by non-powernv platform code. Also include it in the powernv.h
that's local to the platform directory to squash some warnings about
non-static functions missing prototypes.

Also include powernv.h since from opal-memcons.c since it has the
prototypes for the memcons wrangling functions which are used for the opal
and ultravisor msglog.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200804005410.146094-3-oohall@gmail.com

powerpc/powernv/smp: Fix spurious DBG() warning

When building with W=1 we get the following warning:

 arch/powerpc/platforms/powernv/smp.c: In function ‘pnv_smp_cpu_kill_self’:
 arch/powerpc/platforms/powernv/smp.c:276:16: error: suggest braces around
  empty body in an ‘if’ statement [-Werror=empty-body]
   276 |      cpu, srr1);
       |                ^
 cc1: all warnings being treated as errors

The full context is this block:

 if (srr1 && !generic_check_cpu_restart(cpu))
  DBG("CPU%d Unexpected exit while offline srr1=%lx!\n",
  cpu, srr1);

When building with DEBUG undefined DBG() expands to nothing and GCC emits
the warning due to the lack of braces around an empty statement.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200804005410.146094-2-oohall@gmail.com

powerpc/oprofile: fix spelling mistake "contex" -> "context"

There is a spelling mistake in a pr_debug message. Fix it.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200804174316.402425-1-colin.king@canonical.com

powerpc/vmemmap: Don't warn if we don't find a mapping vmemmap list entry

Now that we are handling vmemmap list allocation failure correctly, don't
WARN in section deactivate when we don't find a mapping vmemmap list entry.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200731113500.248306-2-aneesh.kumar@linux.ibm.com

powerpc/vmemmap: Fix memory leak with vmemmap list allocation failures.

If we fail to allocate vmemmap list, we don't keep track of allocated
vmemmap block buf. Hence on section deactivate we skip vmemmap block
buf free. This results in memory leak.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200731113500.248306-1-aneesh.kumar@linux.ibm.com

powerpc/powernv: Remove set but not used variable 'parent'

Fix gcc '-Wunused-but-set-variable' warning:

arch/powerpc/platforms/powernv/pci-ioda.c: In function pnv_ioda_configure_pe:
arch/powerpc/platforms/powernv/pci-ioda.c:867:18: warning: variable parent set but not used [-Wunused-but-set-variable]

It is not used since commit b131a8425c34 ("powerpc/powernv:
Set PELTV for compound PEs")

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1574144074-142032-6-git-send-email-zhengbin13@huawei.com

powerpc/perf: Remove set but not used variable 'target'

Fix gcc '-Wunused-but-set-variable' warning:

arch/powerpc/perf/imc-pmu.c: In function trace_imc_event_init:
arch/powerpc/perf/imc-pmu.c:1292:22: warning: variable target set but not used [-Wunused-but-set-variable]

It is introduced by commit 012ae244845f ("powerpc/perf:
Trace imc PMU functions"), but never used, so remove it.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1574144074-142032-3-git-send-email-zhengbin13@huawei.com

powerpc/fadump: Remove set but not used variable 'elf'

Fix gcc '-Wunused-but-set-variable' warning:

arch/powerpc/kernel/fadump.c: In function fadump_update_elfcore_header:
arch/powerpc/kernel/fadump.c:790:17: warning: variable elf set but not used [-Wunused-but-set-variable]

It is introduced by commit ebaeb5ae2437 ("fadump:
Convert firmware-assisted cpu state dump data into elf notes."),
but never used, so remove it.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1574144074-142032-2-git-send-email-zhengbin13@huawei.com

powerc/dtc/t1024rdb: remove interrupts property

Since the interrupt pin for RTC DS1339 is not connected
to the CPU on T1024RDB, remove the interrupt property
from the device tree.

This also fix the following warning for hwclock.util-linux:
$ hwclock.util-linux
hwclock.util-linux: select() to /dev/rtc0
to wait for clock tick timed out

Signed-off-by: Biwen Li <biwen.li@nxp.com>
Acked-by: Li Yang <leoyang.li@nxp.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200527034228.23793-2-biwen.li@oss.nxp.com

powerpc/dts/t4240rdb: remove interrupts property

Since the interrupt pin for RTC DS1374 is not connected
to the CPU on T4240RDB, remove the interrupt property
from the device tree.

This also fix the following warning for hwclock.util-linux:
$ hwclock.util-linux
hwclock.util-linux: select() to /dev/rtc0
to wait for clock tick timed out

Signed-off-by: Biwen Li <biwen.li@nxp.com>
Acked-by: Li Yang <leoyang.li@nxp.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200527034228.23793-1-biwen.li@oss.nxp.com

cxl: Rework error message for incompatible slots

Improve the error message shown if a capi adapter is plugged on a
capi-incompatible slot directly under the PHB (no intermediate switch).

Fixes: 5632874311db ("cxl: Add support for POWER9 DD2")
Cc: stable@vger.kernel.org # 4.14+
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200407115601.25453-1-fbarrat@linux.ibm.com

ocxl: Remove custom service to allocate interrupts

We now allocate interrupts through xive directly.

Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Acked-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200403153838.29224-5-fbarrat@linux.ibm.com

ocxl: Don't return trigger page when allocating an interrupt

Existing users of ocxl_link_irq_alloc() have been converted to obtain
the trigger page of an interrupt through xive directly, we therefore
have no need to return the trigger page when allocating an interrupt.

It also allows ocxl to use the xive native interface to allocate
interrupts, instead of its custom service.

Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Acked-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200403153838.29224-4-fbarrat@linux.ibm.com

ocxl: Access interrupt trigger page from xive directly

We can access the trigger page through standard APIs so let's use it
and avoid saving it when allocating the interrupt. It will also allow
to simplify allocation in a later patch.

Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Acked-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200403153838.29224-3-fbarrat@linux.ibm.com

scsi: cxlflash: Access interrupt trigger page from xive directly

xive is already mapping the trigger page in kernel space and it can be
accessed through standard APIs, so let's reuse it and simplify the code.

Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Matthew R. Ochs <mrochs@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200403153838.29224-2-fbarrat@linux.ibm.com

powerpc/icp-hv: Fix missing of_node_put() in success path

Both of_find_compatible_node() and of_find_node_by_type() will return
a refcounted node on success - thus for the success path the node must
be explicitly released with a of_node_put().

Fixes: 0b05ac6e2480 ("powerpc/xics: Rewrite XICS driver")
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1530691407-3991-1-git-send-email-hofrat@osadl.org

powerpc/pseries: Fix missing of_node_put() in rng_init()

The call to of_find_compatible_node() returns a node pointer with
refcount incremented thus it must be explicitly decremented here
before returning.

Fixes: a489043f4626 ("powerpc/pseries: Implement arch_get_random_long() based on H_RANDOM")
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1530522496-14816-1-git-send-email-hofrat@osadl.org

selftests/powerpc: Update PROT_SAO test to skip ISA 3.1

Since SAO support was removed from ISA 3.1, skip the
prot_sao test if PPC_FEATURE2_ARCH_3_1 is set.

Signed-off-by: Shawn Anastasio <shawn@anastas.io>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200821185558.35561-4-shawn@anastas.io

powerpc/64s: Disallow PROT_SAO in LPARs by default

Since migration of guests using SAO to ISA 3.1 hosts may cause issues,
disable PROT_SAO in LPARs by default and introduce a new Kconfig option
PPC_PROT_SAO_LPAR to allow users to enable it if desired.

Signed-off-by: Shawn Anastasio <shawn@anastas.io>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200821185558.35561-3-shawn@anastas.io

Revert "powerpc/64s: Remove PROT_SAO support"

This reverts commit 5c9fa16e8abd342ce04dc830c1ebb2a03abf6c05.

Since PROT_SAO can still be useful for certain classes of software,
reintroduce it. Concerns about guest migration for LPARs using SAO
will be addressed next.

Signed-off-by: Shawn Anastasio <shawn@anastas.io>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200821185558.35561-2-shawn@anastas.io