[PATCH 1/3] i386: hvf: Adds support for INVTSC cpuid bit

[Phil Dennis-Jordan <phil@philjordan.eu>]

This patch adds the INVTSC bit to the Hypervisor.framework accelerator's
CPUID bit passthrough allow-list. Previously, specifying +invtsc in the CPU
configuration would fail with the following warning despite the host CPU
advertising the feature:

qemu-system-x86_64: warning: host doesn't support requested feature:
CPUID.80000007H:EDX.invtsc [bit 8]

x86 macOS itself relies on a fixed rate TSC for its own Mach absolute time
timestamp mechanism, so there's no reason we can't enable this bit for guests.

Signed-off-by: Phil Dennis-Jordan <phil@philjordan.eu>
---
 target/i386/hvf/x86_cpuid.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/target/i386/hvf/x86_cpuid.c b/target/i386/hvf/x86_cpuid.c
index 7323a7a94b..d2721bd2a7 100644
--- a/target/i386/hvf/x86_cpuid.c
+++ b/target/i386/hvf/x86_cpuid.c
@@ -145,6 +145,10 @@ uint32_t hvf_get_supported_cpuid(uint32_t func, uint32_t idx,
                 CPUID_EXT3_3DNOWPREFETCH | CPUID_EXT3_OSVW | CPUID_EXT3_XOP |
                 CPUID_EXT3_FMA4 | CPUID_EXT3_TBM;
         break;
+    case 0x80000007:
+        edx &= CPUID_APM_INVTSC;
+        eax = ebx = ecx = 0;
+        break;
     default:
         return 0;
     }
-- 
2.36.1