linux/arch/x86
Vincent Palatin 644c154186 x86, fpu: Avoid FPU lazy restore after suspend
When a cpu enters S3 state, the FPU state is lost.
After resuming for S3, if we try to lazy restore the FPU for a process running
on the same CPU, this will result in a corrupted FPU context.

Ensure that "fpu_owner_task" is properly invalided when (re-)initializing a CPU,
so nobody will try to lazy restore a state which doesn't exist in the hardware.

Tested with a 64-bit kernel on a 4-core Ivybridge CPU with eagerfpu=off,
by doing thousands of suspend/resume cycles with 4 processes doing FPU
operations running. Without the patch, a process is killed after a
few hundreds cycles by a SIGFPE.

Cc: Duncan Laurie <dlaurie@chromium.org>
Cc: Olof Johansson <olofj@chromium.org>
Cc: <stable@kernel.org> v3.4+ # for 3.4 need to replace this_cpu_write by percpu_write
Signed-off-by: Vincent Palatin <vpalatin@chromium.org>
Link: http://lkml.kernel.org/r/1354306532-1014-1-git-send-email-vpalatin@chromium.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-11-30 13:48:05 -08:00
..
boot x86, efi: Fix processor-specific memcpy() build error 2012-11-20 20:52:07 +00:00
configs x86/Kconfig: Turn off DEBUG_NX_TEST module in defconfigs 2012-09-05 10:43:12 +02:00
crypto crypto: aesni - fix XTS mode on x86-32, add wrapper function for asmlinkage aesni_enc() 2012-10-18 14:01:33 -07:00
ia32 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal 2012-10-10 12:02:25 +09:00
include x86, fpu: Avoid FPU lazy restore after suspend 2012-11-30 13:48:05 -08:00
kernel x86, fpu: Avoid FPU lazy restore after suspend 2012-11-30 13:48:05 -08:00
kvm x86, kvm: Remove incorrect redundant assembly constraint 2012-11-26 15:52:48 -08:00
lguest virtio: remove CONFIG_VIRTIO_RING 2012-09-28 15:05:15 +09:30
lib UAPI: x86: Fix insn_sanity build failure after UAPI split 2012-10-02 18:01:56 +01:00
math-emu x86: Rename trap_no to trap_nr in thread_struct 2012-03-13 06:24:09 +01:00
mm x86, mm: Correct vmflag test for checking VM_HUGETLB 2012-11-14 15:03:20 -08:00
net x86: bpf_jit_comp: add XOR instruction for BPF JIT 2012-09-24 16:54:35 -04:00
oprofile oprofile, x86: Fix wrapping bug in op_x86_get_ctrl() 2012-10-15 14:38:24 +02:00
pci x86/ce4100: Fix PCI configuration register access for devices without interrupts 2012-10-30 10:16:47 +01:00
platform x86/ce4100: Fix reboot by forcing the reboot method to be KBD 2012-10-30 10:16:46 +01:00
power x86, kvm: Call restore_sched_clock_state() only after %gs is initialized 2012-04-02 13:53:00 +02:00
realmode x86, suspend: Correct the restore of CR4, EFER; skip computing EFLAGS.ID 2012-10-02 08:42:31 +02:00
syscalls Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal 2012-10-10 12:02:25 +09:00
tools UAPI: x86: Fix the test_get_len tool 2012-10-02 18:01:56 +01:00
um Merge branch 'modules-next' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux 2012-10-14 13:39:34 -07:00
vdso time: Convert x86_64 to using new update_vsyscall 2012-09-24 12:38:09 -04:00
video x86: Use vga_default_device() when determining whether an fb is primary 2012-04-24 09:50:17 +01:00
xen xen/mmu: Use Xen specific TLB flush instead of the generic one. 2012-10-31 12:38:31 -04:00
.gitignore x86/kprobes: Add arch/x86/tools/insn_sanity to .gitignore 2012-01-16 08:21:59 +01:00
Kbuild x86, realmode: realmode.bin infrastructure 2012-05-08 11:41:48 -07:00
Kconfig Merge branch 'modules-next' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux 2012-10-14 13:39:34 -07:00
Kconfig.cpu x86/Kconfig: Clean up Kconfig defaults 2012-09-13 17:45:33 +02:00
Kconfig.debug x86/tlb: add tlb_flushall_shift knob into debugfs 2012-06-27 19:29:10 -07:00
Makefile kbuild: Fix accidental revert in commit fe04ddf 2012-10-15 13:01:05 -07:00
Makefile_32.cpu
Makefile.um um: fix linker script generation 2012-04-09 13:59:00 -04:00