diff options
Diffstat (limited to 'arch/x86/kernel/sev.c')
| -rw-r--r-- | arch/x86/kernel/sev.c | 34 |
1 files changed, 24 insertions, 10 deletions
diff --git a/arch/x86/kernel/sev.c b/arch/x86/kernel/sev.c index 88c46136bbda81..c195ffe5804950 100644 --- a/arch/x86/kernel/sev.c +++ b/arch/x86/kernel/sev.c @@ -648,7 +648,8 @@ static enum es_result vc_handle_msr(struct ghcb *ghcb, struct es_em_ctxt *ctxt) ghcb_set_rdx(ghcb, regs->dx); } - ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_MSR, exit_info_1, 0); + ret = sev_es_ghcb_hv_call(ghcb, true, ctxt, SVM_EXIT_MSR, + exit_info_1, 0); if ((ret == ES_OK) && (!exit_info_1)) { regs->ax = ghcb->save.rax; @@ -867,7 +868,7 @@ static enum es_result vc_do_mmio(struct ghcb *ghcb, struct es_em_ctxt *ctxt, ghcb_set_sw_scratch(ghcb, ghcb_pa + offsetof(struct ghcb, shared_buffer)); - return sev_es_ghcb_hv_call(ghcb, ctxt, exit_code, exit_info_1, exit_info_2); + return sev_es_ghcb_hv_call(ghcb, true, ctxt, exit_code, exit_info_1, exit_info_2); } static enum es_result vc_handle_mmio_twobyte_ops(struct ghcb *ghcb, @@ -1117,7 +1118,7 @@ static enum es_result vc_handle_dr7_write(struct ghcb *ghcb, /* Using a value of 0 for ExitInfo1 means RAX holds the value */ ghcb_set_rax(ghcb, val); - ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_WRITE_DR7, 0, 0); + ret = sev_es_ghcb_hv_call(ghcb, true, ctxt, SVM_EXIT_WRITE_DR7, 0, 0); if (ret != ES_OK) return ret; @@ -1147,7 +1148,7 @@ static enum es_result vc_handle_dr7_read(struct ghcb *ghcb, static enum es_result vc_handle_wbinvd(struct ghcb *ghcb, struct es_em_ctxt *ctxt) { - return sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_WBINVD, 0, 0); + return sev_es_ghcb_hv_call(ghcb, true, ctxt, SVM_EXIT_WBINVD, 0, 0); } static enum es_result vc_handle_rdpmc(struct ghcb *ghcb, struct es_em_ctxt *ctxt) @@ -1156,7 +1157,7 @@ static enum es_result vc_handle_rdpmc(struct ghcb *ghcb, struct es_em_ctxt *ctxt ghcb_set_rcx(ghcb, ctxt->regs->cx); - ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_RDPMC, 0, 0); + ret = sev_es_ghcb_hv_call(ghcb, true, ctxt, SVM_EXIT_RDPMC, 0, 0); if (ret != ES_OK) return ret; @@ -1197,7 +1198,7 @@ static enum es_result vc_handle_vmmcall(struct ghcb *ghcb, if (x86_platform.hyper.sev_es_hcall_prepare) x86_platform.hyper.sev_es_hcall_prepare(ghcb, ctxt->regs); - ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_VMMCALL, 0, 0); + ret = sev_es_ghcb_hv_call(ghcb, true, ctxt, SVM_EXIT_VMMCALL, 0, 0); if (ret != ES_OK) return ret; @@ -1319,13 +1320,26 @@ static __always_inline void vc_forward_exception(struct es_em_ctxt *ctxt) } } -static __always_inline bool on_vc_fallback_stack(struct pt_regs *regs) +static __always_inline bool is_vc2_stack(unsigned long sp) { - unsigned long sp = (unsigned long)regs; - return (sp >= __this_cpu_ist_bottom_va(VC2) && sp < __this_cpu_ist_top_va(VC2)); } +static __always_inline bool vc_from_invalid_context(struct pt_regs *regs) +{ + unsigned long sp, prev_sp; + + sp = (unsigned long)regs; + prev_sp = regs->sp; + + /* + * If the code was already executing on the VC2 stack when the #VC + * happened, let it proceed to the normal handling routine. This way the + * code executing on the VC2 stack can cause #VC exceptions to get handled. + */ + return is_vc2_stack(sp) && !is_vc2_stack(prev_sp); +} + static bool vc_raw_handle_exception(struct pt_regs *regs, unsigned long error_code) { struct ghcb_state state; @@ -1406,7 +1420,7 @@ DEFINE_IDTENTRY_VC_KERNEL(exc_vmm_communication) * But keep this here in case the noinstr annotations are violated due * to bug elsewhere. */ - if (unlikely(on_vc_fallback_stack(regs))) { + if (unlikely(vc_from_invalid_context(regs))) { instrumentation_begin(); panic("Can't handle #VC exception from unsupported context\n"); instrumentation_end(); |