diff options
Diffstat (limited to 'arch/x86/coco')
| -rw-r--r-- | arch/x86/coco/sev/core.c | 23 | ||||
| -rw-r--r-- | arch/x86/coco/sev/vc-handle.c | 31 |
2 files changed, 39 insertions, 15 deletions
diff --git a/arch/x86/coco/sev/core.c b/arch/x86/coco/sev/core.c index fc59ce78c477..14ef5908fb27 100644 --- a/arch/x86/coco/sev/core.c +++ b/arch/x86/coco/sev/core.c @@ -227,6 +227,7 @@ static u64 svsm_build_ca_from_pfn_range(u64 pfn, u64 pfn_end, bool action, pe->page_size = RMP_PG_SIZE_4K; pe->action = action; pe->ignore_cf = 0; + pe->rsvd = 0; pe->pfn = pfn; pe++; @@ -257,6 +258,7 @@ static int svsm_build_ca_from_psc_desc(struct snp_psc_desc *desc, unsigned int d pe->page_size = e->pagesize ? RMP_PG_SIZE_2M : RMP_PG_SIZE_4K; pe->action = e->operation == SNP_PAGE_STATE_PRIVATE; pe->ignore_cf = 0; + pe->rsvd = 0; pe->pfn = e->gfn; pe++; @@ -358,10 +360,31 @@ static void svsm_pval_pages(struct snp_psc_desc *desc) static void pvalidate_pages(struct snp_psc_desc *desc) { + struct psc_entry *e; + unsigned int i; + if (snp_vmpl) svsm_pval_pages(desc); else pval_pages(desc); + + /* + * If not affected by the cache-coherency vulnerability there is no need + * to perform the cache eviction mitigation. + */ + if (cpu_feature_enabled(X86_FEATURE_COHERENCY_SFW_NO)) + return; + + for (i = 0; i <= desc->hdr.end_entry; i++) { + e = &desc->entries[i]; + + /* + * If validating memory (making it private) perform the cache + * eviction mitigation. + */ + if (e->operation == SNP_PAGE_STATE_PRIVATE) + sev_evict_cache(pfn_to_kaddr(e->gfn), e->pagesize ? 512 : 1); + } } static int vmgexit_psc(struct ghcb *ghcb, struct snp_psc_desc *desc) diff --git a/arch/x86/coco/sev/vc-handle.c b/arch/x86/coco/sev/vc-handle.c index faf1fce89ed4..c3b4acbde0d8 100644 --- a/arch/x86/coco/sev/vc-handle.c +++ b/arch/x86/coco/sev/vc-handle.c @@ -371,29 +371,30 @@ static enum es_result __vc_handle_msr_caa(struct pt_regs *regs, bool write) * executing with Secure TSC enabled, so special handling is required for * accesses of MSR_IA32_TSC and MSR_AMD64_GUEST_TSC_FREQ. */ -static enum es_result __vc_handle_secure_tsc_msrs(struct pt_regs *regs, bool write) +static enum es_result __vc_handle_secure_tsc_msrs(struct es_em_ctxt *ctxt, bool write) { + struct pt_regs *regs = ctxt->regs; u64 tsc; /* - * GUEST_TSC_FREQ should not be intercepted when Secure TSC is enabled. - * Terminate the SNP guest when the interception is enabled. + * Writing to MSR_IA32_TSC can cause subsequent reads of the TSC to + * return undefined values, and GUEST_TSC_FREQ is read-only. Generate + * a #GP on all writes. */ - if (regs->cx == MSR_AMD64_GUEST_TSC_FREQ) - return ES_VMM_ERROR; + if (write) { + ctxt->fi.vector = X86_TRAP_GP; + ctxt->fi.error_code = 0; + return ES_EXCEPTION; + } /* - * Writes: Writing to MSR_IA32_TSC can cause subsequent reads of the TSC - * to return undefined values, so ignore all writes. - * - * Reads: Reads of MSR_IA32_TSC should return the current TSC value, use - * the value returned by rdtsc_ordered(). + * GUEST_TSC_FREQ read should not be intercepted when Secure TSC is + * enabled. Terminate the guest if a read is attempted. */ - if (write) { - WARN_ONCE(1, "TSC MSR writes are verboten!\n"); - return ES_OK; - } + if (regs->cx == MSR_AMD64_GUEST_TSC_FREQ) + return ES_VMM_ERROR; + /* Reads of MSR_IA32_TSC should return the current TSC value. */ tsc = rdtsc_ordered(); regs->ax = lower_32_bits(tsc); regs->dx = upper_32_bits(tsc); @@ -416,7 +417,7 @@ static enum es_result vc_handle_msr(struct ghcb *ghcb, struct es_em_ctxt *ctxt) case MSR_IA32_TSC: case MSR_AMD64_GUEST_TSC_FREQ: if (sev_status & MSR_AMD64_SNP_SECURE_TSC) - return __vc_handle_secure_tsc_msrs(regs, write); + return __vc_handle_secure_tsc_msrs(ctxt, write); break; default: break; |