[PATCH V3 5/9] x86/hyperv: Use vmmcall to implement Hyper-V hypercall in sev-snp enlightened guest
From: Tianyu Lan <hidden>
Date: 2023-07-18 03:23:56
Also in:
linux-arch, lkml
Subsystem:
hyper-v/azure core and drivers, the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
"K. Y. Srinivasan", Haiyang Zhang, Wei Liu, Dexuan Cui, Long Li, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
From: Tianyu Lan <redacted> In sev-snp enlightened guest, Hyper-V hypercall needs to use vmmcall to trigger vmexit and notify hypervisor to handle hypercall request. Signed-off-by: Tianyu Lan <redacted> --- arch/x86/include/asm/mshyperv.h | 27 ++++++++++++++------------- 1 file changed, 14 insertions(+), 13 deletions(-)
diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
index 2fa38e9f6207..025eda129d99 100644
--- a/arch/x86/include/asm/mshyperv.h
+++ b/arch/x86/include/asm/mshyperv.h@@ -64,12 +64,12 @@ static inline u64 hv_do_hypercall(u64 control, void *input, void *output) if (!hv_hypercall_pg) return U64_MAX; - __asm__ __volatile__("mov %4, %%r8\n" - CALL_NOSPEC + __asm__ __volatile__("mov %[output], %%r8\n" + ALTERNATIVE("vmmcall", CALL_NOSPEC, X86_FEATURE_SEV_ES) : "=a" (hv_status), ASM_CALL_CONSTRAINT, - "+c" (control), "+d" (input_address) - : "r" (output_address), - THUNK_TARGET(hv_hypercall_pg) + "+c" (control), "+d" (input_address) + : [output] "r" (output_address), + THUNK_TARGET(hv_hypercall_pg) : "cc", "memory", "r8", "r9", "r10", "r11"); #else u32 input_address_hi = upper_32_bits(input_address);
@@ -105,7 +105,8 @@ static inline u64 _hv_do_fast_hypercall8(u64 control, u64 input1) #ifdef CONFIG_X86_64 { - __asm__ __volatile__(CALL_NOSPEC + __asm__ __volatile__("mov %[thunk_target], %%r8\n" + ALTERNATIVE("vmmcall", CALL_NOSPEC, X86_FEATURE_SEV_ES) : "=a" (hv_status), ASM_CALL_CONSTRAINT, "+c" (control), "+d" (input1) : THUNK_TARGET(hv_hypercall_pg)
@@ -150,13 +151,13 @@ static inline u64 _hv_do_fast_hypercall16(u64 control, u64 input1, u64 input2) #ifdef CONFIG_X86_64 { - __asm__ __volatile__("mov %4, %%r8\n" - CALL_NOSPEC - : "=a" (hv_status), ASM_CALL_CONSTRAINT, - "+c" (control), "+d" (input1) - : "r" (input2), - THUNK_TARGET(hv_hypercall_pg) - : "cc", "r8", "r9", "r10", "r11"); + __asm__ __volatile__("mov %[output], %%r8\n" + ALTERNATIVE("vmmcall", CALL_NOSPEC, X86_FEATURE_SEV_ES) + : "=a" (hv_status), ASM_CALL_CONSTRAINT, + "+c" (control), "+d" (input1) + : [output] "r" (input2), + THUNK_TARGET(hv_hypercall_pg) + : "cc", "r8", "r9", "r10", "r11"); } #else {
--
2.25.1