| Message ID | 20241021062226.108657-2-manali.shukla@amd.com |
|---|---|
| State | New |
| Headers | show |
| Series | KVM selftests enhancements | expand |
On Mon, Oct 21, 2024, Manali Shukla wrote: > Add safe_halt() and cli() helpers to processor.h to make them broadly > available in KVM selftests. > > Suggested-by: Sean Christopherson <seanjc@google.com> > Signed-off-by: Manali Shukla <manali.shukla@amd.com> > --- > .../selftests/kvm/include/x86_64/processor.h | 17 +++++++++++++++++ > 1 file changed, 17 insertions(+) The whole point of adding helpers is to use them. I'll post a patch that adds all of the helpers and uses them where possible.
diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h index e247f99e0473..8e36de85b68f 100644 --- a/tools/testing/selftests/kvm/include/x86_64/processor.h +++ b/tools/testing/selftests/kvm/include/x86_64/processor.h @@ -1325,6 +1325,23 @@ static inline void kvm_hypercall_map_gpa_range(uint64_t gpa, uint64_t size, GUEST_ASSERT(!ret); } +/* + * Execute HLT in an STI interrupt shadow to ensure that a pending IRQ that's + * intended to be a wake event arrives *after* HLT is executed. Modern CPUs, + * except for a few oddballs that KVM is unlikely to run on, block IRQs for one + * instruction after STI, *if* RFLAGS.IF=0 before STI. Note, Intel CPUs may + * block other events beyond regular IRQs, e.g. may block NMIs and SMIs too. + */ +static inline void safe_halt(void) +{ + asm volatile("sti; hlt"); +} + +static inline void cli(void) +{ + asm volatile ("cli"); +} + void __vm_xsave_require_permission(uint64_t xfeature, const char *name); #define vm_xsave_require_permission(xfeature) \
Add safe_halt() and cli() helpers to processor.h to make them broadly available in KVM selftests. Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Manali Shukla <manali.shukla@amd.com> --- .../selftests/kvm/include/x86_64/processor.h | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) base-commit: c8d430db8eec7d4fd13a6bea27b7086a54eda6da