| Message ID | 20230618215114.107337-5-pbonzini@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | target/i386: add a few simple features | expand |
On 6/18/23 23:51, Paolo Bonzini wrote: > TCG supports both 32-bit and 64-bit SYSCALL, so expose it > with "-cpu max" even for 32-bit emulators. > > Signed-off-by: Paolo Bonzini<pbonzini@redhat.com> > --- > target/i386/cpu.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) Reviewed-by: Richard Henderson <richard.henderson@linaro.org> r~
Il dom 18 giu 2023, 23:51 Paolo Bonzini <pbonzini@redhat.com> ha scritto: > TCG supports both 32-bit and 64-bit SYSCALL, so expose it > with "-cpu max" even for 32-bit emulators. > Nope, this is broken... My bad for assuming that glibc will use syscall if available—that doesn't happen because the syscall instruction actually is in the vsyscall page or vDSO. The fix is still pretty easy, and even SYSENTER could be supported since after all QEMU *is* exposing the SEP feature when doing user mode emulation. SYSENTER's design is so hideous though, that in practice no program will ever use it outside the vDSO/vsyscall page. Paolo > Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> > --- > target/i386/cpu.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/target/i386/cpu.c b/target/i386/cpu.c > index fc4246223d4..be16c66341d 100644 > --- a/target/i386/cpu.c > +++ b/target/i386/cpu.c > @@ -637,7 +637,7 @@ void x86_cpu_vendor_words2str(char *dst, uint32_t > vendor1, > CPUID_EXT_X2APIC, CPUID_EXT_TSC_DEADLINE_TIMER */ > > #ifdef TARGET_X86_64 > -#define TCG_EXT2_X86_64_FEATURES (CPUID_EXT2_SYSCALL | CPUID_EXT2_LM) > +#define TCG_EXT2_X86_64_FEATURES CPUID_EXT2_LM > #else > #define TCG_EXT2_X86_64_FEATURES 0 > #endif > @@ -645,7 +645,7 @@ void x86_cpu_vendor_words2str(char *dst, uint32_t > vendor1, > #define TCG_EXT2_FEATURES ((TCG_FEATURES & CPUID_EXT2_AMD_ALIASES) | \ > CPUID_EXT2_NX | CPUID_EXT2_MMXEXT | CPUID_EXT2_RDTSCP | \ > CPUID_EXT2_3DNOW | CPUID_EXT2_3DNOWEXT | CPUID_EXT2_PDPE1GB | \ > - TCG_EXT2_X86_64_FEATURES) > + CPUID_EXT2_SYSCALL | TCG_EXT2_X86_64_FEATURES) > #define TCG_EXT3_FEATURES (CPUID_EXT3_LAHF_LM | CPUID_EXT3_SVM | \ > CPUID_EXT3_CR8LEG | CPUID_EXT3_ABM | CPUID_EXT3_SSE4A | \ > CPUID_EXT3_3DNOWPREFETCH) > -- > 2.40.1 > >
diff --git a/target/i386/cpu.c b/target/i386/cpu.c index fc4246223d4..be16c66341d 100644 --- a/target/i386/cpu.c +++ b/target/i386/cpu.c @@ -637,7 +637,7 @@ void x86_cpu_vendor_words2str(char *dst, uint32_t vendor1, CPUID_EXT_X2APIC, CPUID_EXT_TSC_DEADLINE_TIMER */ #ifdef TARGET_X86_64 -#define TCG_EXT2_X86_64_FEATURES (CPUID_EXT2_SYSCALL | CPUID_EXT2_LM) +#define TCG_EXT2_X86_64_FEATURES CPUID_EXT2_LM #else #define TCG_EXT2_X86_64_FEATURES 0 #endif @@ -645,7 +645,7 @@ void x86_cpu_vendor_words2str(char *dst, uint32_t vendor1, #define TCG_EXT2_FEATURES ((TCG_FEATURES & CPUID_EXT2_AMD_ALIASES) | \ CPUID_EXT2_NX | CPUID_EXT2_MMXEXT | CPUID_EXT2_RDTSCP | \ CPUID_EXT2_3DNOW | CPUID_EXT2_3DNOWEXT | CPUID_EXT2_PDPE1GB | \ - TCG_EXT2_X86_64_FEATURES) + CPUID_EXT2_SYSCALL | TCG_EXT2_X86_64_FEATURES) #define TCG_EXT3_FEATURES (CPUID_EXT3_LAHF_LM | CPUID_EXT3_SVM | \ CPUID_EXT3_CR8LEG | CPUID_EXT3_ABM | CPUID_EXT3_SSE4A | \ CPUID_EXT3_3DNOWPREFETCH)
TCG supports both 32-bit and 64-bit SYSCALL, so expose it with "-cpu max" even for 32-bit emulators. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> --- target/i386/cpu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)