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mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-27 06:34:11 +08:00
linux-next/include
Peter Zijlstra acb04058de sched/clock: Fix hotplug crash
Mike reported that he could trigger the WARN_ON_ONCE() in
set_sched_clock_stable() using hotplug.

This exposed a fundamental problem with the interface, we should never
mark the TSC stable if we ever find it to be unstable. Therefore
set_sched_clock_stable() is a broken interface.

The reason it existed is that not having it is a pain, it means all
relevant architecture code needs to call clear_sched_clock_stable()
where appropriate.

Of the three architectures that select HAVE_UNSTABLE_SCHED_CLOCK ia64
and parisc are trivial in that they never called
set_sched_clock_stable(), so add an unconditional call to
clear_sched_clock_stable() to them.

For x86 the story is a lot more involved, and what this patch tries to
do is ensure we preserve the status quo. So even is Cyrix or Transmeta
have usable TSC they never called set_sched_clock_stable() so they now
get an explicit mark unstable.

Reported-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 9881b024b7 ("sched/clock: Delay switching sched_clock to stable")
Link: http://lkml.kernel.org/r/20170119133633.GB6536@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-20 02:38:46 +01:00
..
acpi More ACPI updates for v4.10-rc1 2016-12-22 10:19:32 -08:00
asm-generic asm-prototypes: Clear any CPP defines before declaring the functions 2017-01-05 12:57:42 +01:00
clocksource
crypto This pull contains one set of changes: a conversion of the crypto DocBook 2016-12-17 16:00:34 -08:00
drm Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
dt-bindings dt-bindings: mfd: Remove TPS65217 interrupts 2016-12-27 10:06:00 -08:00
keys
kvm clocksource: Use a plain u64 instead of cycle_t 2016-12-25 11:04:12 +01:00
linux sched/clock: Fix hotplug crash 2017-01-20 02:38:46 +01:00
math-emu
media
memory
misc
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-12-27 16:04:37 -08:00
pcmcia
ras
rdma Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
rxrpc
scsi linux: drop __bitwise__ everywhere 2016-12-16 00:13:41 +02:00
soc powerpc updates for 4.10 2016-12-16 09:26:42 -08:00
sound Merge remote-tracking branches 'asoc/fix/arizona', 'asoc/fix/dpcm', 'asoc/fix/dwc', 'asoc/fix/fsl-ssi' and 'asoc/fix/hdmi-codec' into asoc-linus 2017-01-10 10:47:50 +00:00
target target: add XCOPY target/segment desc sense codes 2017-01-10 08:40:32 -08:00
trace Merge branch 'for-linus-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2017-01-13 17:40:22 -08:00
uapi timerfd: export defines to userspace 2017-01-10 18:31:55 -08:00
video
xen xen: features and fixes for 4.10 rc0 2016-12-13 16:07:55 -08:00
Kbuild