diff options
author | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-02-10 11:12:55 -0800 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-02-10 11:13:53 -0800 |
commit | 7483948fdd31a8642ef0288aab6f368b98d53c29 (patch) | |
tree | 031020a5553701d2aae8dddb0fa509aa65854eb1 /arch/x86/kvm/emulate.c | |
parent | 22a416c4e0f2179b57028e084ac0ed2c110333bd (diff) | |
parent | fe250923bbbbcbccc9aa7b84d05ee7a060450534 (diff) |
Merge tag 'usb-3.3-rc3' into usb-next
This is done to resolve a merge conflict with:
drivers/usb/class/cdc-wdm.c
and to better handle future patches for this driver as it is under
active development at the moment.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/x86/kvm/emulate.c')
-rw-r--r-- | arch/x86/kvm/emulate.c | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 05a562b8502..0982507b962 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -1891,6 +1891,51 @@ setup_syscalls_segments(struct x86_emulate_ctxt *ctxt, ss->p = 1; } +static bool em_syscall_is_enabled(struct x86_emulate_ctxt *ctxt) +{ + struct x86_emulate_ops *ops = ctxt->ops; + u32 eax, ebx, ecx, edx; + + /* + * syscall should always be enabled in longmode - so only become + * vendor specific (cpuid) if other modes are active... + */ + if (ctxt->mode == X86EMUL_MODE_PROT64) + return true; + + eax = 0x00000000; + ecx = 0x00000000; + if (ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx)) { + /* + * Intel ("GenuineIntel") + * remark: Intel CPUs only support "syscall" in 64bit + * longmode. Also an 64bit guest with a + * 32bit compat-app running will #UD !! While this + * behaviour can be fixed (by emulating) into AMD + * response - CPUs of AMD can't behave like Intel. + */ + if (ebx == X86EMUL_CPUID_VENDOR_GenuineIntel_ebx && + ecx == X86EMUL_CPUID_VENDOR_GenuineIntel_ecx && + edx == X86EMUL_CPUID_VENDOR_GenuineIntel_edx) + return false; + + /* AMD ("AuthenticAMD") */ + if (ebx == X86EMUL_CPUID_VENDOR_AuthenticAMD_ebx && + ecx == X86EMUL_CPUID_VENDOR_AuthenticAMD_ecx && + edx == X86EMUL_CPUID_VENDOR_AuthenticAMD_edx) + return true; + + /* AMD ("AMDisbetter!") */ + if (ebx == X86EMUL_CPUID_VENDOR_AMDisbetterI_ebx && + ecx == X86EMUL_CPUID_VENDOR_AMDisbetterI_ecx && + edx == X86EMUL_CPUID_VENDOR_AMDisbetterI_edx) + return true; + } + + /* default: (not Intel, not AMD), apply Intel's stricter rules... */ + return false; +} + static int em_syscall(struct x86_emulate_ctxt *ctxt) { struct x86_emulate_ops *ops = ctxt->ops; @@ -1904,9 +1949,15 @@ static int em_syscall(struct x86_emulate_ctxt *ctxt) ctxt->mode == X86EMUL_MODE_VM86) return emulate_ud(ctxt); + if (!(em_syscall_is_enabled(ctxt))) + return emulate_ud(ctxt); + ops->get_msr(ctxt, MSR_EFER, &efer); setup_syscalls_segments(ctxt, &cs, &ss); + if (!(efer & EFER_SCE)) + return emulate_ud(ctxt); + ops->get_msr(ctxt, MSR_STAR, &msr_data); msr_data >>= 32; cs_sel = (u16)(msr_data & 0xfffc); |