Messages in this thread | | | Date | Thu, 7 May 2020 15:28:00 +0200 | From | Borislav Petkov <> | Subject | Re: [PATCH v3 07/10] x86/fpu/xstate: Update copy_kernel_to_xregs_err() for XSAVES supervisor states |
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On Sat, Mar 28, 2020 at 09:43:04AM -0700, Yu-cheng Yu wrote: > The function copy_kernel_to_xregs_err() uses XRSTOR, which can work with > standard or compacted format without supervisor xstates. However, when > supervisor xstates are present, XRSTORS must be used. Fix it by using > XRSTORS when XSAVES is enabled. > > I also considered if there were additional cases where XRSTOR might be > mistakenly called instead of XRSTORS. There are only three XRSTOR sites > in kernel: > > 1. copy_kernel_to_xregs_booting(), already switches between XRSTOR and > XRSTORS based on X86_FEATURE_XSAVES. > 2. copy_user_to_xregs(), which *needs* XRSTOR because it is copying from > userspace and must never copy supervisor state with XRSTORS. > 3. copy_kernel_to_xregs_err() mistakenly used XRSTOR only. Fixed in > this patch.
Avoid having "This patch" or "This commit" in the commit message. It is tautologically useless.
Also, do
$ git grep 'This patch' Documentation/process
for more details.
-- Regards/Gruss, Boris.
https://people.kernel.org/tglx/notes-about-netiquette
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