diff options
author | Chao Gao <chao.gao@intel.com> | 2025-05-06 17:36:07 +0800 |
---|---|---|
committer | Ingo Molnar <mingo@kernel.org> | 2025-05-06 11:52:22 +0200 |
commit | 32d5fa804dc9bd7cf6651a1378ba616d332e7444 (patch) | |
tree | 59421418a59b80f5e6a5cb43ece2777516456a33 | |
parent | d8414603b29f25191fcceafb72e74b67ac2e92b1 (diff) |
x86/fpu: Drop @perm from guest pseudo FPU container
Remove @perm from the guest pseudo FPU container. The field is
initialized during allocation and never used later.
Rename fpu_init_guest_permissions() to show that its sole purpose is to
lock down guest permissions.
Suggested-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Chao Gao <chao.gao@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Chang S. Bae <chang.seok.bae@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Eric Biggers <ebiggers@google.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <kees@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mitchell Levy <levymitchell0@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Samuel Holland <samuel.holland@sifive.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/kvm/af972fe5981b9e7101b64de43c7be0a8cc165323.camel@redhat.com/
Link: https://lore.kernel.org/r/20250506093740.2864458-3-chao.gao@intel.com
-rw-r--r-- | arch/x86/include/asm/fpu/types.h | 7 | ||||
-rw-r--r-- | arch/x86/kernel/fpu/core.c | 7 |
2 files changed, 2 insertions, 12 deletions
diff --git a/arch/x86/include/asm/fpu/types.h b/arch/x86/include/asm/fpu/types.h index e64db0eb9d27..1c94121acd3d 100644 --- a/arch/x86/include/asm/fpu/types.h +++ b/arch/x86/include/asm/fpu/types.h @@ -536,13 +536,6 @@ struct fpu_guest { u64 xfeatures; /* - * @perm: xfeature bitmap of features which are - * permitted to be enabled for the guest - * vCPU. - */ - u64 perm; - - /* * @xfd_err: Save the guest value. */ u64 xfd_err; diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index 105b1b80d88d..1cda5b78540b 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -212,7 +212,7 @@ void fpu_reset_from_exception_fixup(void) #if IS_ENABLED(CONFIG_KVM) static void __fpstate_reset(struct fpstate *fpstate, u64 xfd); -static void fpu_init_guest_permissions(struct fpu_guest *gfpu) +static void fpu_lock_guest_permissions(void) { struct fpu_state_perm *fpuperm; u64 perm; @@ -228,8 +228,6 @@ static void fpu_init_guest_permissions(struct fpu_guest *gfpu) WRITE_ONCE(fpuperm->__state_perm, perm | FPU_GUEST_PERM_LOCKED); spin_unlock_irq(¤t->sighand->siglock); - - gfpu->perm = perm & ~FPU_GUEST_PERM_LOCKED; } bool fpu_alloc_guest_fpstate(struct fpu_guest *gfpu) @@ -250,7 +248,6 @@ bool fpu_alloc_guest_fpstate(struct fpu_guest *gfpu) gfpu->fpstate = fpstate; gfpu->xfeatures = fpu_kernel_cfg.default_features; - gfpu->perm = fpu_kernel_cfg.default_features; /* * KVM sets the FP+SSE bits in the XSAVE header when copying FPU state @@ -265,7 +262,7 @@ bool fpu_alloc_guest_fpstate(struct fpu_guest *gfpu) if (WARN_ON_ONCE(fpu_user_cfg.default_size > gfpu->uabi_size)) gfpu->uabi_size = fpu_user_cfg.default_size; - fpu_init_guest_permissions(gfpu); + fpu_lock_guest_permissions(); return true; } |