x86/fpu/xstate: Prepare XSAVE feature table for gaps in state component numbers
authorChang S. Bae <chang.seok.bae@intel.com>
Thu, 21 Oct 2021 22:55:23 +0000 (15:55 -0700)
committerBorislav Petkov <bp@suse.de>
Tue, 26 Oct 2021 08:53:02 +0000 (10:53 +0200)
commit70c3f1671b0cbc386b387f1de33b7837e276a195
treeef68ec1e7a55192c5249d3e6b99f022569d87526
parent500afbf645a040a39e1af0dba2fdf6ebf224bd47
x86/fpu/xstate: Prepare XSAVE feature table for gaps in state component numbers

The kernel checks at boot time which features are available by walking a
XSAVE feature table which contains the CPUID feature bit numbers which need
to be checked whether a feature is available on a CPU or not. So far the
feature numbers have been linear, but AMX will create a gap which the
current code cannot handle.

Make the table entries explicitly indexed and adjust the loop code
accordingly to prepare for that.

No functional change.

Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Len Brown <len.brown@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20211021225527.10184-20-chang.seok.bae@intel.com
arch/x86/kernel/fpu/xstate.c