cachepc-qemu

Fork of AMDESE/qemu with changes for cachepc side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-qemu
Log | Files | Refs | Submodules | LICENSE | sfeed.txt
commit 3ba1aea797bcf29a772544bf849c3c66481dd52f
parent 3b6a2b6b7466f6dea53243900b7516c3f29027b7
Author: Louis Burda <quent.burda@gmail.com>
Date:   Wed,  8 Feb 2023 20:16:20 +0100

Disable AES-NI instructions in CPUID report

Diffstat:

Mtarget/i386/sev.c | 3+++


1 file changed, 3 insertions(+), 0 deletions(-)

diff --git a/target/i386/sev.c b/target/i386/sev.c
@@ -1242,6 +1242,9 @@ sev_snp_cpuid_info_fill(SnpCpuidInfo *snp_cpuid_info,
         snp_cpuid_entry->ecx = kvm_cpuid_entry->ecx;
         snp_cpuid_entry->edx = kvm_cpuid_entry->edx;
 
+        /* CachePC: disable AES-NI */
+        snp_cpuid_entry->ecx &= ~(1 << 25);
+
         /*
          * Guest kernels will calculate EBX themselves using the 0xD
          * subfunctions corresponding to the individual XSAVE areas, so only