[tip: x86/fpu] x86/fpu/apx: Enable APX state support

[tip-bot2 for Chang S. Bae]

The following commit has been merged into the x86/fpu branch of tip:

Commit-ID:     50c5b071e2833d2b61e3774cd792620311df157c
Gitweb:        https://git.kernel.org/tip/50c5b071e2833d2b61e3774cd792620311df157c
Author:        Chang S. Bae <chang.seok.bae@xxxxxxxxx>
AuthorDate:    Tue, 15 Apr 2025 19:16:54 -07:00
Committer:     Ingo Molnar <mingo@xxxxxxxxxx>
CommitterDate: Wed, 16 Apr 2025 09:44:14 +02:00

x86/fpu/apx: Enable APX state support

With securing APX against conflicting MPX, it is now ready to be enabled.
Include APX in the enabled xfeature set.

Signed-off-by: Chang S. Bae <chang.seok.bae@xxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Reviewed-by: Sohil Mehta <sohil.mehta@xxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Oleg Nesterov <oleg@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20250416021720.12305-5-chang.seok.bae@xxxxxxxxx
---
 arch/x86/include/asm/fpu/xstate.h | 3 ++-
 arch/x86/kernel/fpu/xstate.c      | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/fpu/xstate.h b/arch/x86/include/asm/fpu/xstate.h
index 7f39fe7..b308a76 100644
--- a/arch/x86/include/asm/fpu/xstate.h
+++ b/arch/x86/include/asm/fpu/xstate.h
@@ -32,7 +32,8 @@
 				      XFEATURE_MASK_PKRU | \
 				      XFEATURE_MASK_BNDREGS | \
 				      XFEATURE_MASK_BNDCSR | \
-				      XFEATURE_MASK_XTILE)
+				      XFEATURE_MASK_XTILE | \
+				      XFEATURE_MASK_APX)
 
 /*
  * Features which are restored when returning to user space.
diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
index 14f5c1b..2ac1fc1 100644
--- a/arch/x86/kernel/fpu/xstate.c
+++ b/arch/x86/kernel/fpu/xstate.c
@@ -371,7 +371,8 @@ static __init void os_xrstor_booting(struct xregs_state *xstate)
 	 XFEATURE_MASK_BNDCSR |			\
 	 XFEATURE_MASK_PASID |			\
 	 XFEATURE_MASK_CET_USER |		\
-	 XFEATURE_MASK_XTILE)
+	 XFEATURE_MASK_XTILE |			\
+	 XFEATURE_MASK_APX)
 
 /*
  * setup the xstate image representing the init state