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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 12/22/25 22:33, Paolo Bonzini wrote: > The only difference is usage of switch_fpu_return() vs. > fpregs_restore_userregs(). In turn, these are only different > if there is no FPU at all, but KVM requires one. Therefore use the > pre-made export---the code is simpler and there is no functional change. > > Signed-off-by: Paolo Bonzini > --- > arch/x86/kernel/fpu/core.c | 2 +- > arch/x86/kvm/fpu.h | 6 +----- > 2 files changed, 2 insertions(+), 6 deletions(-) > > diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c > index 3ab27fb86618..8ded41b023a2 100644 > --- a/arch/x86/kernel/fpu/core.c > +++ b/arch/x86/kernel/fpu/core.c > @@ -858,7 +858,6 @@ void switch_fpu_return(void) > > fpregs_restore_userregs(); > } > -EXPORT_SYMBOL_FOR_KVM(switch_fpu_return); Oops, unlike in my tree (patch to be sent tomorrow after I write a testcase) there's still an occurrence of switch_fpu_return() in vcpu_enter_guest(). Paolo > void fpregs_lock_and_load(void) > { > @@ -877,6 +876,7 @@ void fpregs_lock_and_load(void) > > fpregs_assert_state_consistent(); > } > +EXPORT_SYMBOL_FOR_KVM(fpregs_lock_and_load); > > #ifdef CONFIG_X86_DEBUG_FPU > /* > diff --git a/arch/x86/kvm/fpu.h b/arch/x86/kvm/fpu.h > index f898781b6a06..b6a03d8fa8af 100644 > --- a/arch/x86/kvm/fpu.h > +++ b/arch/x86/kvm/fpu.h > @@ -149,11 +149,7 @@ static inline void _kvm_write_mmx_reg(int reg, const u64 *data) > > static inline void kvm_fpu_get(void) > { > - fpregs_lock(); > - > - fpregs_assert_state_consistent(); > - if (test_thread_flag(TIF_NEED_FPU_LOAD)) > - switch_fpu_return(); > + fpregs_lock_and_load(); > } > > static inline void kvm_fpu_put(void)