Messages in this thread Patch in this message | | | Date | Mon, 11 Jul 2016 09:13:22 -0700 | From | tip-bot for Yu-cheng Yu <> | Subject | [tip:x86/fpu] x86/fpu/xstate: Return NULL for disabled xstate component address |
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Commit-ID: 5060b91513b866f774da15dfd82157864c4b1683 Gitweb: http://git.kernel.org/tip/5060b91513b866f774da15dfd82157864c4b1683 Author: Yu-cheng Yu <yu-cheng.yu@intel.com> AuthorDate: Mon, 11 Jul 2016 09:18:55 -0700 Committer: Ingo Molnar <mingo@kernel.org> CommitDate: Mon, 11 Jul 2016 16:44:00 +0200
x86/fpu/xstate: Return NULL for disabled xstate component address
It is an error to request a disabled XSAVE/XSAVES component address. For that case, make __raw_xsave_addr() return a NULL and issue a warning.
Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com> Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Reviewed-by: Dave Hansen <dave.hansen@intel.com> Cc: H. Peter Anvin <h.peter.anvin@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi V Shankar <ravi.v.shankar@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1468253937-40008-3-git-send-email-fenghua.yu@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> --- arch/x86/kernel/fpu/xstate.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index f8d1aff..4fb8dd7 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -760,6 +760,11 @@ void *__raw_xsave_addr(struct xregs_state *xsave, int xstate_feature_mask) { int feature_nr = fls64(xstate_feature_mask) - 1; + if (!xfeature_enabled(feature_nr)) { + WARN_ON_FPU(1); + return NULL; + } + return (void *)xsave + xstate_comp_offsets[feature_nr]; } /*
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