linux-toradex.git/arch/x86, branch v4.10

x86/vm86: Fix unused variable warning if THP is disabled

2017-02-13T18:04:38+00:00

GCC complains about unused variable 'vma' in mark_screen_rdonly() if THP is
disabled:

arch/x86/kernel/vm86_32.c: In function ‘mark_screen_rdonly’:
arch/x86/kernel/vm86_32.c:180:26: warning: unused variable ‘vma’
[-Wunused-variable]
   struct vm_area_struct *vma = find_vma(mm, 0xA0000);

That's silly. pmd_trans_huge() resolves to 0 when THP is disabled, so the
whole block should be eliminated.

Moving the variable declaration outside the if() block shuts GCC up.

Reported-by: Jérémy Lefaure 
Signed-off-by: Kirill A. Shutemov 
Tested-by: Borislav Petkov 
Cc: Carlos O'Donell 
Link: http://lkml.kernel.org/r/20170213125228.63645-1-kirill.shutemov@linux.intel.com
Signed-off-by: Thomas Gleixner

Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2017-02-11T18:31:46+00:00

Pull x86 fixes from Ingo Molnar:
 "Last minute x86 fixes:

   - Fix a softlockup detector warning and long delays if using ptdump
     with KASAN enabled.

   - Two more TSC-adjust fixes for interesting firmware interactions.

   - Two commits to fix an AMD CPU topology enumeration bug that caused
     a measurable gaming performance regression"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm/ptdump: Fix soft lockup in page table walker
  x86/tsc: Make the TSC ADJUST sanitizing work for tsc_reliable
  x86/tsc: Avoid the large time jump when sanitizing TSC ADJUST
  x86/CPU/AMD: Fix Zen SMT topology
  x86/CPU/AMD: Bring back Compute Unit ID

x86/mm/ptdump: Fix soft lockup in page table walker

2017-02-10T10:00:23+00:00

CONFIG_KASAN=y needs a lot of virtual memory mapped for its shadow.
In that case ptdump_walk_pgd_level_core() takes a lot of time to
walk across all page tables and doing this without
a rescheduling causes soft lockups:

 NMI watchdog: BUG: soft lockup - CPU#3 stuck for 23s! [swapper/0:1]
 ...
 Call Trace:
  ptdump_walk_pgd_level_core+0x40c/0x550
  ptdump_walk_pgd_level_checkwx+0x17/0x20
  mark_rodata_ro+0x13b/0x150
  kernel_init+0x2f/0x120
  ret_from_fork+0x2c/0x40

I guess that this issue might arise even without KASAN on huge machines
with several terabytes of RAM.

Stick cond_resched() in pgd loop to fix this.

Reported-by: Tobias Regnery 
Signed-off-by: Andrey Ryabinin 
Cc: kasan-dev@googlegroups.com
Cc: Alexander Potapenko 
Cc: "Paul E . McKenney" 
Cc: Dmitry Vyukov 
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20170210095405.31802-1-aryabinin@virtuozzo.com
Signed-off-by: Thomas Gleixner

x86/tsc: Make the TSC ADJUST sanitizing work for tsc_reliable

2017-02-10T08:47:17+00:00

When the TSC is marked reliable then the synchronization check is skipped,
but that also skips the TSC ADJUST sanitizing code. So on a machine with a
wreckaged BIOS the TSC deviation between CPUs might go unnoticed.

Let the TSC adjust sanitizing code run unconditionally and just skip the
expensive synchronization checks when TSC is marked reliable.

Signed-off-by: Thomas Gleixner 
Cc: Peter Zijlstra 
Cc: Olof Johansson 
Link: http://lkml.kernel.org/r/20170209151231.491189912@linutronix.de
Signed-off-by: Thomas Gleixner

x86/tsc: Avoid the large time jump when sanitizing TSC ADJUST

2017-02-10T08:47:16+00:00

Olof reported that on a machine which has a BIOS wreckaged TSC the
timestamps in dmesg are making a large jump because the TSC value is
jumping forward after resetting the TSC ADJUST register to a sane value.

This can be avoided by calling the TSC ADJUST saniziting function before
initializing the per cpu sched clock machinery. That takes the offset into
account and avoid the time jump.

What cannot be avoided is that the 'Firmware Bug' warnings on the secondary
CPUs are printed with the large time offsets because it would be too much
effort and ugly hackery to print those warnings into a buffer and emit them
after the adjustemt on the starting CPUs. It's a firmware bug and should be
fixed in firmware. The weird timestamps are collateral damage and just
illustrate the sillyness of the BIOS folks:

[    0.397445] smp: Bringing up secondary CPUs ...
[    0.402100] x86: Booting SMP configuration:
[    0.406343] .... node  #0, CPUs:      #1
[1265776479.930667] [Firmware Bug]: TSC ADJUST differs: Reference CPU0: -2978888639075328 CPU1: -2978888639183101
[1265776479.944664] TSC ADJUST synchronize: Reference CPU0: 0 CPU1: -2978888639183101
[    0.508119]  #2
[1265776480.032346] [Firmware Bug]: TSC ADJUST differs: Reference CPU0: -2978888639075328 CPU2: -2978888639183677
[1265776480.044192] TSC ADJUST synchronize: Reference CPU0: 0 CPU2: -2978888639183677
[    0.607643]  #3
[1265776480.131874] [Firmware Bug]: TSC ADJUST differs: Reference CPU0: -2978888639075328 CPU3: -2978888639184530
[1265776480.143720] TSC ADJUST synchronize: Reference CPU0: 0 CPU3: -2978888639184530
[    0.707108] smp: Brought up 1 node, 4 CPUs
[    0.711271] smpboot: Total of 4 processors activated (21698.88 BogoMIPS)

Reported-by: Olof Johansson 
Signed-off-by: Thomas Gleixner 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/20170209151231.411460506@linutronix.de
Signed-off-by: Thomas Gleixner

Revert "x86/ioapic: Restore IO-APIC irq_chip retrigger callback"

2017-02-09T02:08:29+00:00

This reverts commit 020eb3daaba2857b32c4cf4c82f503d6a00a67de.

Gabriel C reports that it causes his machine to not boot, and we haven't
tracked down the reason for it yet.  Since the bug it fixes has been
around for a longish time, we're better off reverting the fix for now.

Gabriel says:
 "It hangs early and freezes with a lot RCU warnings.

  I bisected it down to :

  > Ruslan Ruslichenko (1):
  >       x86/ioapic: Restore IO-APIC irq_chip retrigger callback

  Reverting this one fixes the problem for me..

  The box is a PRIMERGY TX200 S5 , 2 socket , 2 x E5520 CPU(s) installed"

and Ruslan and Thomas are currently stumped.

Reported-and-bisected-by: Gabriel C 
Cc: Ruslan Ruslichenko 
Cc: Thomas Gleixner 
Cc: stable@kernel.org   # for the backport of the original commit
Signed-off-by: Linus Torvalds

Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6

2017-02-06T22:16:23+00:00

Pull crypto fixes from Herbert Xu:

 - use-after-free in algif_aead

 - modular aesni regression when pcbc is modular but absent

 - bug causing IO page faults in ccp

 - double list add in ccp

 - NULL pointer dereference in qat (two patches)

 - panic in chcr

 - NULL pointer dereference in chcr

 - out-of-bound access in chcr

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: chcr - Fix key length for RFC4106
  crypto: algif_aead - Fix kernel panic on list_del
  crypto: aesni - Fix failure when pcbc module is absent
  crypto: ccp - Fix double add when creating new DMA command
  crypto: ccp - Fix DMA operations when IOMMU is enabled
  crypto: chcr - Check device is allocated before use
  crypto: chcr - Fix panic on dma_unmap_sg
  crypto: qat - zero esram only for DH85x devices
  crypto: qat - fix bar discovery for c62x

x86/CPU/AMD: Fix Zen SMT topology

2017-02-05T11:18:45+00:00

After:

  a33d331761bc ("x86/CPU/AMD: Fix Bulldozer topology")

our  SMT scheduling topology for Fam17h systems is broken, because
the ThreadId is included in the ApicId when SMT is enabled.

So, without further decoding cpu_core_id is unique for each thread
rather than the same for threads on the same core. This didn't affect
systems with SMT disabled. Make cpu_core_id be what it is defined to be.

Signed-off-by: Yazen Ghannam 
Signed-off-by: Borislav Petkov 
Cc:  # 4.9
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/20170205105022.8705-2-bp@alien8.de
Signed-off-by: Ingo Molnar

x86/CPU/AMD: Bring back Compute Unit ID

2017-02-05T11:18:45+00:00

Commit:

  a33d331761bc ("x86/CPU/AMD: Fix Bulldozer topology")

restored the initial approach we had with the Fam15h topology of
enumerating CU (Compute Unit) threads as cores. And this is still
correct - they're beefier than HT threads but still have some
shared functionality.

Our current approach has a problem with the Mad Max Steam game, for
example. Yves Dionne reported a certain "choppiness" while playing on
v4.9.5.

That problem stems most likely from the fact that the CU threads share
resources within one CU and when we schedule to a thread of a different
compute unit, this incurs latency due to migrating the working set to a
different CU through the caches.

When the thread siblings mask mirrors that aspect of the CUs and
threads, the scheduler pays attention to it and tries to schedule within
one CU first. Which takes care of the latency, of course.

Reported-by: Yves Dionne 
Signed-off-by: Borislav Petkov 
Cc:  # 4.9
Cc: Brice Goglin 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: Yazen Ghannam 
Link: http://lkml.kernel.org/r/20170205105022.8705-1-bp@alien8.de
Signed-off-by: Ingo Molnar

Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2017-02-04T20:18:01+00:00

Pull irq fixes from Thomas Gleixner:

 - Prevent double activation of interrupt lines, which causes problems
   on certain interrupt controllers

 - Handle the fallout of the above because x86 (ab)uses the activation
   function to reconfigure interrupts under the hood.

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/irq: Make irq activate operations symmetric
  irqdomain: Avoid activating interrupts more than once