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| author | Chang S. Bae <chang.seok.bae@intel.com> | 2021-10-22 01:55:21 +0300 |
|---|---|---|
| committer | Borislav Petkov <bp@suse.de> | 2021-10-26 11:53:02 +0300 |
| commit | 783e87b404956f8958657aed8a6a72aa98d5b7e1 (patch) | |
| tree | a7d6b08b8ca1045a43d668a482fe6f83238882cd /arch/x86/include/asm/fpu | |
| parent | 672365477ae8afca5a1cca98c1deb733235e4525 (diff) | |
| download | linux-783e87b404956f8958657aed8a6a72aa98d5b7e1.tar.xz | |
x86/fpu/xstate: Add XFD #NM handler
If the XFD MSR has feature bits set then #NM will be raised when user space
attempts to use an instruction related to one of these features.
When the task has no permissions to use that feature, raise SIGILL, which
is the same behavior as #UD.
If the task has permissions, calculate the new buffer size for the extended
feature set and allocate a larger fpstate. In the unlikely case that
vzalloc() fails, SIGSEGV is raised.
The allocation function will be added in the next step. Provide a stub
which fails for now.
[ tglx: Updated serialization ]
Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20211021225527.10184-18-chang.seok.bae@intel.com
Diffstat (limited to 'arch/x86/include/asm/fpu')
| -rw-r--r-- | arch/x86/include/asm/fpu/xstate.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/x86/include/asm/fpu/xstate.h b/arch/x86/include/asm/fpu/xstate.h index cf285464eabe..b7b145cad019 100644 --- a/arch/x86/include/asm/fpu/xstate.h +++ b/arch/x86/include/asm/fpu/xstate.h @@ -99,6 +99,8 @@ int xfeature_size(int xfeature_nr); void xsaves(struct xregs_state *xsave, u64 mask); void xrstors(struct xregs_state *xsave, u64 mask); +int xfd_enable_feature(u64 xfd_err); + #ifdef CONFIG_X86_64 DECLARE_STATIC_KEY_FALSE(__fpu_state_size_dynamic); #endif |