linux/arch
Janakarajan Natarajan 88d879d29f Prevent timer value 0 for MWAITX
Newer hardware has uncovered a bug in the software implementation of
using MWAITX for the delay function. A value of 0 for the timer is meant
to indicate that a timeout will not be used to exit MWAITX. On newer
hardware this can result in MWAITX never returning, resulting in NMI
soft lockup messages being printed. On older hardware, some of the other
conditions under which MWAITX can exit masked this issue. The AMD APM
does not currently document this and will be updated.

Please refer to http://marc.info/?l=kvm&m=148950623231140 for
information regarding NMI soft lockup messages on an AMD Ryzen 1800X.
This has been root-caused as a 0 passed to MWAITX causing it to wait
indefinitely.

This change has the added benefit of avoiding the unnecessary setup of
MONITORX/MWAITX when the delay value is zero.

Signed-off-by: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Link: http://lkml.kernel.org/r/1493156643-29366-1-git-send-email-Janakarajan.Natarajan@amd.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-30 13:35:11 +02:00
..
alpha sched/headers: Move task->mm handling methods to <linux/sched/mm.h> 2017-03-03 01:43:28 +01:00
arc ARC udpates for 4.11-rc5 2017-04-01 10:52:19 -07:00
arm sound fixes for 4.11-rc5 2017-03-31 11:53:49 -07:00
arm64 arm64: drop non-existing vdso-offsets.h from .gitignore 2017-03-30 19:29:30 +01:00
avr32 arch, mm: convert all architectures to use 5level-fixup.h 2017-03-09 11:48:47 -08:00
blackfin sched/headers: Move task->mm handling methods to <linux/sched/mm.h> 2017-03-03 01:43:28 +01:00
c6x Merge branch 'regset' (PTRACE_SETREGSET data leakage) 2017-03-29 08:55:25 -07:00
cris Merge branch 'prep-for-5level' 2017-03-10 08:59:07 -08:00
frv arch, mm: convert all architectures to use 5level-fixup.h 2017-03-09 11:48:47 -08:00
h8300 Merge branch 'regset' (PTRACE_SETREGSET data leakage) 2017-03-29 08:55:25 -07:00
hexagon arch, mm: convert all architectures to use 5level-fixup.h 2017-03-09 11:48:47 -08:00
ia64 arch, mm: convert all architectures to use 5level-fixup.h 2017-03-09 11:48:47 -08:00
m32r sched/headers: Move task->mm handling methods to <linux/sched/mm.h> 2017-03-03 01:43:28 +01:00
m68k m68k: Wire up statx 2017-03-20 11:27:28 +01:00
metag Merge branch 'regset' (PTRACE_SETREGSET data leakage) 2017-03-29 08:55:25 -07:00
microblaze arch, mm: convert all architectures to use 5level-fixup.h 2017-03-09 11:48:47 -08:00
mips Merge branch 'regset' (PTRACE_SETREGSET data leakage) 2017-03-29 08:55:25 -07:00
mn10300 arch, mm: convert all architectures to use 5level-fixup.h 2017-03-09 11:48:47 -08:00
nios2 nios2: reserve boot memory for device tree 2017-04-02 20:13:57 -07:00
openrisc openrisc: Export symbols needed by modules 2017-03-16 00:12:57 +09:00
parisc parisc: Avoid stalled CPU warnings after system shutdown 2017-03-29 21:50:38 +02:00
powerpc Revert "powerpc/64: Disable use of radix under a hypervisor" 2017-03-21 16:50:28 +11:00
s390 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2017-04-03 08:44:43 -07:00
score Fixup for arch/score after extable.h introduction 2017-03-11 14:16:50 -08:00
sh Merge branch 'prep-for-5level' 2017-03-10 08:59:07 -08:00
sparc Merge branch 'regset' (PTRACE_SETREGSET data leakage) 2017-03-29 08:55:25 -07:00
tile arch, mm: convert all architectures to use 5level-fixup.h 2017-03-09 11:48:47 -08:00
um arch, mm: convert all architectures to use 5level-fixup.h 2017-03-09 11:48:47 -08:00
unicore32 arch, mm: convert all architectures to use 5level-fixup.h 2017-03-09 11:48:47 -08:00
x86 Prevent timer value 0 for MWAITX 2017-04-30 13:35:11 +02:00
xtensa xtensa: wire up statx system call 2017-03-31 16:26:21 -07:00
.gitignore
Kconfig scripts/spelling.txt: add "an user" pattern and fix typo instances 2017-02-27 18:43:46 -08:00