linux-stable.git/arch/powerpc/kernel, branch v5.4.8

powerpc/book3s/mm: Update Oops message to print the correct translation in use

2020-01-04T18:18:10+00:00

[ Upstream commit d7e02f7b7991dbe14a2acfb0e53d675cd149001c ]

Avoids confusion when printing Oops message like below

 Faulting instruction address: 0xc00000000008bdb4
 Oops: Kernel access of bad area, sig: 11 [#1]
 LE PAGE_SIZE=64K MMU=Radix MMU=Hash SMP NR_CPUS=2048 NUMA PowerNV

This was because we never clear the MMU_FTR_HPTE_TABLE feature flag
even if we run with radix translation. It was discussed that we should
look at this feature flag as an indication of the capability to run
hash translation and we should not clear the flag even if we run in
radix translation. All the code paths check for radix_enabled() check and
if found true consider we are running with radix translation. Follow the
same sequence for finding the MMU translation string to be used in Oops
message.

Signed-off-by: Aneesh Kumar K.V 
Acked-by: Nicholas Piggin 
Reviewed-by: Christophe Leroy 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20190711145814.17970-1-aneesh.kumar@linux.ibm.com
Signed-off-by: Sasha Levin

powerpc/eeh: differentiate duplicate detection message

2020-01-04T18:18:10+00:00

[ Upstream commit de84ffc3ccbeec3678f95a3d898fc188efa0d9c5 ]

Currently when an EEH error is detected, the system log receives the
same (or almost the same) message twice:

  EEH: PHB#0 failure detected, location: N/A
  EEH: PHB#0 failure detected, location: N/A
or
  EEH: eeh_dev_check_failure: Frozen PHB#0-PE#0 detected
  EEH: Frozen PHB#0-PE#0 detected

This looks like a bug, but in fact the messages are from different
functions and mean slightly different things.  So keep both but change
one of the messages slightly, so that it's clear they are different:

  EEH: PHB#0 failure detected, location: N/A
  EEH: Recovering PHB#0, location: N/A
or
  EEH: eeh_dev_check_failure: Frozen PHB#0-PE#0 detected
  EEH: Recovering PHB#0-PE#0

Signed-off-by: Sam Bobroff 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/43817cb6e6631b0828b9a6e266f60d1f8ca8eb22.1571288375.git.sbobroff@linux.ibm.com
Signed-off-by: Sasha Levin

powerpc/security: Fix wrong message when RFI Flush is disable

2020-01-04T18:18:03+00:00

[ Upstream commit 4e706af3cd8e1d0503c25332b30cad33c97ed442 ]

The issue was showing "Mitigation" message via sysfs whatever the
state of "RFI Flush", but it should show "Vulnerable" when it is
disabled.

If you have "L1D private" feature enabled and not "RFI Flush" you are
vulnerable to meltdown attacks.

"RFI Flush" is the key feature to mitigate the meltdown whatever the
"L1D private" state.

SEC_FTR_L1D_THREAD_PRIV is a feature for Power9 only.

So the message should be as the truth table shows:

  CPU | L1D private | RFI Flush |                sysfs
  ----|-------------|-----------|-------------------------------------
   P9 |    False    |   False   | Vulnerable
   P9 |    False    |   True    | Mitigation: RFI Flush
   P9 |    True     |   False   | Vulnerable: L1D private per thread
   P9 |    True     |   True    | Mitigation: RFI Flush, L1D private per thread
   P8 |    False    |   False   | Vulnerable
   P8 |    False    |   True    | Mitigation: RFI Flush

Output before this fix:
  # cat /sys/devices/system/cpu/vulnerabilities/meltdown
  Mitigation: RFI Flush, L1D private per thread
  # echo 0 > /sys/kernel/debug/powerpc/rfi_flush
  # cat /sys/devices/system/cpu/vulnerabilities/meltdown
  Mitigation: L1D private per thread

Output after fix:
  # cat /sys/devices/system/cpu/vulnerabilities/meltdown
  Mitigation: RFI Flush, L1D private per thread
  # echo 0 > /sys/kernel/debug/powerpc/rfi_flush
  # cat /sys/devices/system/cpu/vulnerabilities/meltdown
  Vulnerable: L1D private per thread

Signed-off-by: Gustavo L. F. Walbon 
Signed-off-by: Mauro S. M. Rodrigues 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20190502210907.42375-1-gwalbon@linux.ibm.com
Signed-off-by: Sasha Levin

powerpc/security/book3s64: Report L1TF status in sysfs

2020-01-04T18:17:11+00:00

[ Upstream commit 8e6b6da91ac9b9ec5a925b6cb13f287a54bd547d ]

Some PowerPC CPUs are vulnerable to L1TF to the same extent as to
Meltdown. It is also mitigated by flushing the L1D on privilege
transition.

Currently the sysfs gives a false negative on L1TF on CPUs that I
verified to be vulnerable, a Power9 Talos II Boston 004e 1202, PowerNV
T2P9D01.

Signed-off-by: Anthony Steinhauser 
Signed-off-by: Michael Ellerman 
[mpe: Just have cpu_show_l1tf() call cpu_show_meltdown() directly]
Link: https://lore.kernel.org/r/20191029190759.84821-1-asteinhauser@google.com
Signed-off-by: Sasha Levin

powerpc/pseries: Mark accumulate_stolen_time() as notrace

2020-01-04T18:16:50+00:00

[ Upstream commit eb8e20f89093b64f48975c74ccb114e6775cee22 ]

accumulate_stolen_time() is called prior to interrupt state being
reconciled, which can trip the warning in arch_local_irq_restore():

  WARNING: CPU: 5 PID: 1017 at arch/powerpc/kernel/irq.c:258 .arch_local_irq_restore+0x9c/0x130
  ...
  NIP .arch_local_irq_restore+0x9c/0x130
  LR  .rb_start_commit+0x38/0x80
  Call Trace:
    .ring_buffer_lock_reserve+0xe4/0x620
    .trace_function+0x44/0x210
    .function_trace_call+0x148/0x170
    .ftrace_ops_no_ops+0x180/0x1d0
    ftrace_call+0x4/0x8
    .accumulate_stolen_time+0x1c/0xb0
    decrementer_common+0x124/0x160

For now just mark it as notrace. We may change the ordering to call it
after interrupt state has been reconciled, but that is a larger
change.

Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20191024055932.27940-1-mpe@ellerman.id.au
Signed-off-by: Sasha Levin

powerpc/irq: fix stack overflow verification

2019-12-31T15:46:29+00:00

commit 099bc4812f09155da77eeb960a983470249c9ce1 upstream.

Before commit 0366a1c70b89 ("powerpc/irq: Run softirqs off the top of
the irq stack"), check_stack_overflow() was called by do_IRQ(), before
switching to the irq stack.
In that commit, do_IRQ() was renamed __do_irq(), and is now executing
on the irq stack, so check_stack_overflow() has just become almost
useless.

Move check_stack_overflow() call in do_IRQ() to do the check while
still on the current stack.

Fixes: 0366a1c70b89 ("powerpc/irq: Run softirqs off the top of the irq stack")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/e033aa8116ab12b7ca9a9c75189ad0741e3b9b5f.1575872340.git.christophe.leroy@c-s.fr
Signed-off-by: Greg Kroah-Hartman

powerpc: Fix vDSO clock_getres()

2019-12-17T18:56:47+00:00

[ Upstream commit 552263456215ada7ee8700ce022d12b0cffe4802 ]

clock_getres in the vDSO library has to preserve the same behaviour
of posix_get_hrtimer_res().

In particular, posix_get_hrtimer_res() does:
    sec = 0;
    ns = hrtimer_resolution;
and hrtimer_resolution depends on the enablement of the high
resolution timers that can happen either at compile or at run time.

Fix the powerpc vdso implementation of clock_getres keeping a copy of
hrtimer_resolution in vdso data and using that directly.

Fixes: a7f290dad32e ("[PATCH] powerpc: Merge vdso's and add vdso support to 32 bits kernel")
Cc: stable@vger.kernel.org
Signed-off-by: Vincenzo Frascino 
Reviewed-by: Christophe Leroy 
Acked-by: Shuah Khan 
[chleroy: changed CLOCK_REALTIME_RES to CLOCK_HRTIMER_RES]
Signed-off-by: Christophe Leroy 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/a55eca3a5e85233838c2349783bcb5164dae1d09.1575273217.git.christophe.leroy@c-s.fr
Signed-off-by: Sasha Levin

powerpc: Avoid clang warnings around setjmp and longjmp

2019-12-17T18:56:47+00:00

[ Upstream commit c9029ef9c95765e7b63c4d9aa780674447db1ec0 ]

Commit aea447141c7e ("powerpc: Disable -Wbuiltin-requires-header when
setjmp is used") disabled -Wbuiltin-requires-header because of a
warning about the setjmp and longjmp declarations.

r367387 in clang added another diagnostic around this, complaining
that there is no jmp_buf declaration.

  In file included from ../arch/powerpc/xmon/xmon.c:47:
  ../arch/powerpc/include/asm/setjmp.h:10:13: error: declaration of
  built-in function 'setjmp' requires the declaration of the 'jmp_buf'
  type, commonly provided in the header .
  [-Werror,-Wincomplete-setjmp-declaration]
  extern long setjmp(long *);
              ^
  ../arch/powerpc/include/asm/setjmp.h:11:13: error: declaration of
  built-in function 'longjmp' requires the declaration of the 'jmp_buf'
  type, commonly provided in the header .
  [-Werror,-Wincomplete-setjmp-declaration]
  extern void longjmp(long *, long);
              ^
  2 errors generated.

We are not using the standard library's longjmp/setjmp implementations
for obvious reasons; make this clear to clang by using -ffreestanding
on these files.

Cc: stable@vger.kernel.org # 4.14+
Suggested-by: Segher Boessenkool 
Reviewed-by: Nick Desaulniers 
Signed-off-by: Nathan Chancellor 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20191119045712.39633-3-natechancellor@gmail.com
Signed-off-by: Sasha Levin

powerpc: Allow flush_icache_range to work across ranges >4GB

2019-12-17T18:56:42+00:00

commit 29430fae82073d39b1b881a3cd507416a56a363f upstream.

When calling flush_icache_range with a size >4GB, we were masking
off the upper 32 bits, so we would incorrectly flush a range smaller
than intended.

This patch replaces the 32 bit shifts with 64 bit ones, so that
the full size is accounted for.

Signed-off-by: Alastair D'Silva 
Cc: stable@vger.kernel.org
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20191104023305.9581-2-alastair@au1.ibm.com
Signed-off-by: Greg Kroah-Hartman

powerpc: Allow 64bit VDSO __kernel_sync_dicache to work across ranges >4GB

2019-12-17T18:56:41+00:00

commit f9ec11165301982585e5e5f606739b5bae5331f3 upstream.

When calling __kernel_sync_dicache with a size >4GB, we were masking
off the upper 32 bits, so we would incorrectly flush a range smaller
than intended.

This patch replaces the 32 bit shifts with 64 bit ones, so that
the full size is accounted for.

Signed-off-by: Alastair D'Silva 
Cc: stable@vger.kernel.org
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20191104023305.9581-3-alastair@au1.ibm.com
Signed-off-by: Greg Kroah-Hartman