From patchwork Wed Oct 14 17:09:20 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: test for lm capable kernel. X-Patchwork-Submitter: Glauber Costa X-Patchwork-Id: 35998 Message-Id: <1255540160-19869-1-git-send-email-glommer@redhat.com> To: qemu-devel@nongnu.org Cc: aliguori@us.ibm.com Date: Wed, 14 Oct 2009 14:09:20 -0300 From: Glauber Costa List-Id: qemu-devel.nongnu.org Don't save x86_64-specific msrs if our kernel does not support them. Code is already in qemu-kvm.git, but the test function is slightly different. It follows what the test for msr_start does. Signed-off-by: Glauber Costa --- target-i386/kvm.c | 37 +++++++++++++++++++++++++++---------- 1 files changed, 27 insertions(+), 10 deletions(-) diff --git a/target-i386/kvm.c b/target-i386/kvm.c index 7010999..0e69b57 100644 --- a/target-i386/kvm.c +++ b/target-i386/kvm.c @@ -15,6 +15,7 @@ #include #include #include +#include #include @@ -266,6 +267,20 @@ static int kvm_has_msr_star(CPUState *env) return 0; } +static int lm_capable_kernel(void) +{ + static int lm_capable = -1; + struct utsname utsname; + + if (lm_capable != -1) { + return lm_capable; + } + + uname(&utsname); + lm_capable = (strcmp(utsname.machine, "x86_64") == 0); + return lm_capable; +} + int kvm_arch_init(KVMState *s, int smp_cpus) { int ret; @@ -478,11 +493,12 @@ static int kvm_put_msrs(CPUState *env) kvm_msr_entry_set(&msrs[n++], MSR_STAR, env->star); kvm_msr_entry_set(&msrs[n++], MSR_IA32_TSC, env->tsc); #ifdef TARGET_X86_64 - /* FIXME if lm capable */ - kvm_msr_entry_set(&msrs[n++], MSR_CSTAR, env->cstar); - kvm_msr_entry_set(&msrs[n++], MSR_KERNELGSBASE, env->kernelgsbase); - kvm_msr_entry_set(&msrs[n++], MSR_FMASK, env->fmask); - kvm_msr_entry_set(&msrs[n++], MSR_LSTAR, env->lstar); + if (lm_capable_kernel()) { + kvm_msr_entry_set(&msrs[n++], MSR_CSTAR, env->cstar); + kvm_msr_entry_set(&msrs[n++], MSR_KERNELGSBASE, env->kernelgsbase); + kvm_msr_entry_set(&msrs[n++], MSR_FMASK, env->fmask); + kvm_msr_entry_set(&msrs[n++], MSR_LSTAR, env->lstar); + } #endif msr_data.info.nmsrs = n; @@ -611,11 +627,12 @@ static int kvm_get_msrs(CPUState *env) msrs[n++].index = MSR_STAR; msrs[n++].index = MSR_IA32_TSC; #ifdef TARGET_X86_64 - /* FIXME lm_capable_kernel */ - msrs[n++].index = MSR_CSTAR; - msrs[n++].index = MSR_KERNELGSBASE; - msrs[n++].index = MSR_FMASK; - msrs[n++].index = MSR_LSTAR; + if (lm_capable_kernel()) { + msrs[n++].index = MSR_CSTAR; + msrs[n++].index = MSR_KERNELGSBASE; + msrs[n++].index = MSR_FMASK; + msrs[n++].index = MSR_LSTAR; + } #endif msr_data.info.nmsrs = n; ret = kvm_vcpu_ioctl(env, KVM_GET_MSRS, &msr_data);