diff options
| author | Andy Lutomirski <[email protected]> | 2015-09-20 16:32:05 -0700 |
|---|---|---|
| committer | Thomas Gleixner <[email protected]> | 2015-09-22 22:40:36 +0200 |
| commit | 83c133cf11fb0e68a51681447e372489f052d40e (patch) | |
| tree | 216347000c44ee61270ab02cba8a838b01ee3f4f /drivers/iommu/amd_iommu_init.c | |
| parent | fc57a7c68020dcf954428869eafd934c0ab1536f (diff) | |
x86/nmi/64: Fix a paravirt stack-clobbering bug in the NMI code
The NMI entry code that switches to the normal kernel stack needs to
be very careful not to clobber any extra stack slots on the NMI
stack. The code is fine under the assumption that SWAPGS is just a
normal instruction, but that assumption isn't really true. Use
SWAPGS_UNSAFE_STACK instead.
This is part of a fix for some random crashes that Sasha saw.
Fixes: 9b6e6a8334d5 ("x86/nmi/64: Switch stacks on userspace NMI entry")
Reported-and-tested-by: Sasha Levin <[email protected]>
Signed-off-by: Andy Lutomirski <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/974bc40edffdb5c2950a5c4977f821a446b76178.1442791737.git.luto@kernel.org
Signed-off-by: Thomas Gleixner <[email protected]>
Diffstat (limited to 'drivers/iommu/amd_iommu_init.c')
0 files changed, 0 insertions, 0 deletions