diff options
| author | Yu-cheng Yu <yu-cheng.yu@intel.com> | 2016-07-11 09:18:56 -0700 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2016-07-11 16:44:00 +0200 |
| commit | 35ac2d7ba787eb4b7418a5a6f5919c25e10a780a (patch) | |
| tree | 735223525166e0cdaf3451d0c401adf4267a8435 /arch/x86/include/asm/fpu | |
| parent | 5060b91513b866f774da15dfd82157864c4b1683 (diff) | |
x86/fpu/xstate: Fix fpstate_init() for XRSTORS
In XSAVES mode if fpstate_init() is used to initialize a
task's extended state area, xsave.header.xcomp_bv[63] must
be set. Otherwise, when the task is scheduled, a warning is
triggered from copy_kernel_to_xregs().
One such test case is: setting an invalid extended state
through PTRACE. When xstateregs_set() rejects the syscall
and re-initializes the task's extended state area. This triggers
the warning mentioned above.
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/1468253937-40008-4-git-send-email-fenghua.yu@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/include/asm/fpu')
| -rw-r--r-- | arch/x86/include/asm/fpu/types.h | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/arch/x86/include/asm/fpu/types.h b/arch/x86/include/asm/fpu/types.h index 12dd648735b6..48df486b02f9 100644 --- a/arch/x86/include/asm/fpu/types.h +++ b/arch/x86/include/asm/fpu/types.h @@ -232,6 +232,12 @@ struct xstate_header { } __attribute__((packed)); /* + * xstate_header.xcomp_bv[63] indicates that the extended_state_area + * is in compacted format. + */ +#define XCOMP_BV_COMPACTED_FORMAT ((u64)1 << 63) + +/* * This is our most modern FPU state format, as saved by the XSAVE * and restored by the XRSTOR instructions. * |