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charset="utf-8" Force sev_es_host_save_area() to be always inlined, as it's used in the low level VM-Enter/VM-Exit path, which is non-instrumentable. vmlinux.o: warning: objtool: svm_vcpu_enter_exit+0xb0: call to sev_es_host_save_area() leaves .noinstr.text section vmlinux.o: warning: objtool: svm_vcpu_enter_exit+0xbf: call to sev_es_host_save_area.isra.0() leaves .noinstr.text section Fixes: c92be2fd8edf ("KVM: SVM: Save/restore non-volatile GPRs in SEV-ES VM= RUN via host save area") Reported-by: Borislav Petkov Signed-off-by: Sean Christopherson Tested-by: Borislav Petkov (AMD) --- arch/x86/kvm/svm/svm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 9ac6fca50cf3..0a36c82b316f 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -1504,7 +1504,7 @@ static void svm_vcpu_free(struct kvm_vcpu *vcpu) __free_pages(virt_to_page(svm->msrpm), get_order(MSRPM_SIZE)); } =20 -static struct sev_es_save_area *sev_es_host_save_area(struct svm_cpu_data = *sd) +static __always_inline struct sev_es_save_area *sev_es_host_save_area(stru= ct svm_cpu_data *sd) { return page_address(sd->save_area) + 0x400; 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charset="utf-8" Use sev_es_host_save_area() instead of open coding an equivalent when setting the MSR_TSC_AUX field during setup. No functional change intended. Signed-off-by: Sean Christopherson --- arch/x86/kvm/svm/svm.c | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-) diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 0a36c82b316f..cf285472fea6 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -570,6 +570,11 @@ static void __svm_write_tsc_multiplier(u64 multiplier) __this_cpu_write(current_tsc_ratio, multiplier); } =20 +static __always_inline struct sev_es_save_area *sev_es_host_save_area(stru= ct svm_cpu_data *sd) +{ + return page_address(sd->save_area) + 0x400; +} + static inline void kvm_cpu_svm_disable(void) { uint64_t efer; @@ -674,12 +679,9 @@ static int svm_hardware_enable(void) * TSC_AUX field now to avoid a RDMSR on every vCPU run. */ if (boot_cpu_has(X86_FEATURE_V_TSC_AUX)) { - struct sev_es_save_area *hostsa; u32 __maybe_unused msr_hi; =20 - hostsa =3D (struct sev_es_save_area *)(page_address(sd->save_area) + 0x4= 00); - - rdmsr(MSR_TSC_AUX, hostsa->tsc_aux, msr_hi); + rdmsr(MSR_TSC_AUX, sev_es_host_save_area(sd)->tsc_aux, msr_hi); 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charset="utf-8" When reading MSR_TSC_AUX, which is effectively a 32-bit value, use a compound literal to consume/ignore the upper 32 bits instead of a "maybe" unused local variable. While (ab)using a compound literal to discard an unused output is unusual, it's perfectly legal as compound literals are valid, modifiable l-values in C99 and beyond. No functional change intended. Signed-off-by: Sean Christopherson --- arch/x86/kvm/svm/svm.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index cf285472fea6..69c0dea5cc0d 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -678,11 +678,8 @@ static int svm_hardware_enable(void) * Since Linux does not change the value of TSC_AUX once set, prime the * TSC_AUX field now to avoid a RDMSR on every vCPU run. */ - if (boot_cpu_has(X86_FEATURE_V_TSC_AUX)) { - u32 __maybe_unused msr_hi; - - rdmsr(MSR_TSC_AUX, sev_es_host_save_area(sd)->tsc_aux, msr_hi); - } + if (boot_cpu_has(X86_FEATURE_V_TSC_AUX)) + rdmsr(MSR_TSC_AUX, sev_es_host_save_area(sd)->tsc_aux, (u32){0}); =20 return 0; } --=20 2.45.2.627.g7a2c4fd464-goog