[PATCH] x86/sev-es: Expose __sev_es_ghcb_hv_call() to call ghcb hv call out of sev code
From: Tianyu Lan <hidden>
Date: 2021-10-20 06:23:32
Also in:
linux-hyperv, lkml, netdev
Subsystem:
the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
From: Tianyu Lan <redacted> Hyper-V also needs to call ghcb hv call to write/read MSR in Isolation VM. So expose __sev_es_ghcb_hv_call() to call it in the Hyper-V code. Signed-off-by: Tianyu Lan <redacted> --- arch/x86/include/asm/sev.h | 11 +++++++++++ arch/x86/kernel/sev-shared.c | 24 +++++++++++++++++++----- 2 files changed, 30 insertions(+), 5 deletions(-)
diff --git a/arch/x86/include/asm/sev.h b/arch/x86/include/asm/sev.h
index fa5cd05d3b5b..295c847c3cd4 100644
--- a/arch/x86/include/asm/sev.h
+++ b/arch/x86/include/asm/sev.h@@ -81,12 +81,23 @@ static __always_inline void sev_es_nmi_complete(void) __sev_es_nmi_complete(); } extern int __init sev_es_efi_map_ghcbs(pgd_t *pgd); +extern enum es_result __sev_es_ghcb_hv_call(struct ghcb *ghcb, + struct es_em_ctxt *ctxt, + u64 exit_code, u64 exit_info_1, + u64 exit_info_2); #else static inline void sev_es_ist_enter(struct pt_regs *regs) { } static inline void sev_es_ist_exit(void) { } static inline int sev_es_setup_ap_jump_table(struct real_mode_header *rmh) { return 0; } static inline void sev_es_nmi_complete(void) { } static inline int sev_es_efi_map_ghcbs(pgd_t *pgd) { return 0; } +static inline enum es_result +__sev_es_ghcb_hv_call(struct ghcb *ghcb, + u64 exit_code, u64 exit_info_1, + u64 exit_info_2) +{ + return ES_VMM_ERROR; +} #endif #endif
diff --git a/arch/x86/kernel/sev-shared.c b/arch/x86/kernel/sev-shared.c
index ea9abd69237e..08c97cb057fa 100644
--- a/arch/x86/kernel/sev-shared.c
+++ b/arch/x86/kernel/sev-shared.c@@ -124,10 +124,14 @@ static enum es_result verify_exception_info(struct ghcb *ghcb, struct es_em_ctxt return ES_VMM_ERROR; } -static enum es_result sev_es_ghcb_hv_call(struct ghcb *ghcb, - struct es_em_ctxt *ctxt, - u64 exit_code, u64 exit_info_1, - u64 exit_info_2) +/* + * __sev_es_ghcb_hv_call() is also used in the other platform code(e.g + * Hyper-V). + */ +enum es_result __sev_es_ghcb_hv_call(struct ghcb *ghcb, + struct es_em_ctxt *ctxt, + u64 exit_code, u64 exit_info_1, + u64 exit_info_2) { /* Fill in protocol and format specifiers */ ghcb->protocol_version = GHCB_PROTOCOL_MAX;
@@ -137,12 +141,22 @@ static enum es_result sev_es_ghcb_hv_call(struct ghcb *ghcb, ghcb_set_sw_exit_info_1(ghcb, exit_info_1); ghcb_set_sw_exit_info_2(ghcb, exit_info_2); - sev_es_wr_ghcb_msr(__pa(ghcb)); VMGEXIT(); return verify_exception_info(ghcb, ctxt); } +static enum es_result sev_es_ghcb_hv_call(struct ghcb *ghcb, + struct es_em_ctxt *ctxt, + u64 exit_code, u64 exit_info_1, + u64 exit_info_2) +{ + sev_es_wr_ghcb_msr(__pa(ghcb)); + + return __sev_es_ghcb_hv_call(ghcb, ctxt, exit_code, exit_info_1, + exit_info_2); +} + /* * Boot VC Handler - This is the first VC handler during boot, there is no GHCB * page yet, so it only supports the MSR based communication with the
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2.25.1