]> Gentwo Git Trees - linux/.git/commit
x86/fpu/xstate: Remove xstate offset check
authorChang S. Bae <chang.seok.bae@intel.com>
Thu, 20 Mar 2025 23:42:52 +0000 (16:42 -0700)
committerIngo Molnar <mingo@kernel.org>
Mon, 14 Apr 2025 06:18:29 +0000 (08:18 +0200)
commit031b33ef1a6a1129a1a02a16b89608ded2eff9be
tree2de5c5338329607badf74c4fbc6a6abae6aac987
parent8ffd015db85fea3e15a77027fda6c02ced4d2444
x86/fpu/xstate: Remove xstate offset check

Traditionally, new xstate components have been assigned sequentially,
aligning feature numbers with their offsets in the XSAVE buffer. However,
this ordering is not architecturally mandated in the non-compacted
format, where a component's offset may not correspond to its feature
number.

The kernel caches CPUID-reported xstate component details, including size
and offset in the non-compacted format. As part of this process, a sanity
check is also conducted to ensure alignment between feature numbers and
offsets.

This check was likely intended as a general guideline rather than a
strict requirement. Upcoming changes will support out-of-order offsets.
Remove the check as becoming obsolete.

Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Link: https://lore.kernel.org/r/20250320234301.8342-2-chang.seok.bae@intel.com
arch/x86/kernel/fpu/xstate.c