Merge branch 'kvm-updates/2.6.36' of git://git.kernel.org/pub/scm/virt/kvm/kvm

* 'kvm-updates/2.6.36' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: Fix fs/gs reload oops with invalid ldt
This commit is contained in:
Linus Torvalds 2010-10-20 09:00:44 -07:00
commit ef2533dae5
3 changed files with 19 additions and 44 deletions

View File

@ -652,20 +652,6 @@ static inline struct kvm_mmu_page *page_header(hpa_t shadow_page)
return (struct kvm_mmu_page *)page_private(page);
}
static inline u16 kvm_read_fs(void)
{
u16 seg;
asm("mov %%fs, %0" : "=g"(seg));
return seg;
}
static inline u16 kvm_read_gs(void)
{
u16 seg;
asm("mov %%gs, %0" : "=g"(seg));
return seg;
}
static inline u16 kvm_read_ldt(void)
{
u16 ldt;
@ -673,16 +659,6 @@ static inline u16 kvm_read_ldt(void)
return ldt;
}
static inline void kvm_load_fs(u16 sel)
{
asm("mov %0, %%fs" : : "rm"(sel));
}
static inline void kvm_load_gs(u16 sel)
{
asm("mov %0, %%gs" : : "rm"(sel));
}
static inline void kvm_load_ldt(u16 sel)
{
asm("lldt %0" : : "rm"(sel));

View File

@ -3163,8 +3163,8 @@ static void svm_vcpu_run(struct kvm_vcpu *vcpu)
sync_lapic_to_cr8(vcpu);
save_host_msrs(vcpu);
fs_selector = kvm_read_fs();
gs_selector = kvm_read_gs();
savesegment(fs, fs_selector);
savesegment(gs, gs_selector);
ldt_selector = kvm_read_ldt();
svm->vmcb->save.cr2 = vcpu->arch.cr2;
/* required for live migration with NPT */
@ -3251,10 +3251,15 @@ static void svm_vcpu_run(struct kvm_vcpu *vcpu)
vcpu->arch.regs[VCPU_REGS_RSP] = svm->vmcb->save.rsp;
vcpu->arch.regs[VCPU_REGS_RIP] = svm->vmcb->save.rip;
kvm_load_fs(fs_selector);
kvm_load_gs(gs_selector);
kvm_load_ldt(ldt_selector);
load_host_msrs(vcpu);
loadsegment(fs, fs_selector);
#ifdef CONFIG_X86_64
load_gs_index(gs_selector);
wrmsrl(MSR_KERNEL_GS_BASE, current->thread.gs);
#else
loadsegment(gs, gs_selector);
#endif
kvm_load_ldt(ldt_selector);
reload_tss(vcpu);

View File

@ -803,7 +803,7 @@ static void vmx_save_host_state(struct kvm_vcpu *vcpu)
*/
vmx->host_state.ldt_sel = kvm_read_ldt();
vmx->host_state.gs_ldt_reload_needed = vmx->host_state.ldt_sel;
vmx->host_state.fs_sel = kvm_read_fs();
savesegment(fs, vmx->host_state.fs_sel);
if (!(vmx->host_state.fs_sel & 7)) {
vmcs_write16(HOST_FS_SELECTOR, vmx->host_state.fs_sel);
vmx->host_state.fs_reload_needed = 0;
@ -811,7 +811,7 @@ static void vmx_save_host_state(struct kvm_vcpu *vcpu)
vmcs_write16(HOST_FS_SELECTOR, 0);
vmx->host_state.fs_reload_needed = 1;
}
vmx->host_state.gs_sel = kvm_read_gs();
savesegment(gs, vmx->host_state.gs_sel);
if (!(vmx->host_state.gs_sel & 7))
vmcs_write16(HOST_GS_SELECTOR, vmx->host_state.gs_sel);
else {
@ -841,27 +841,21 @@ static void vmx_save_host_state(struct kvm_vcpu *vcpu)
static void __vmx_load_host_state(struct vcpu_vmx *vmx)
{
unsigned long flags;
if (!vmx->host_state.loaded)
return;
++vmx->vcpu.stat.host_state_reload;
vmx->host_state.loaded = 0;
if (vmx->host_state.fs_reload_needed)
kvm_load_fs(vmx->host_state.fs_sel);
loadsegment(fs, vmx->host_state.fs_sel);
if (vmx->host_state.gs_ldt_reload_needed) {
kvm_load_ldt(vmx->host_state.ldt_sel);
/*
* If we have to reload gs, we must take care to
* preserve our gs base.
*/
local_irq_save(flags);
kvm_load_gs(vmx->host_state.gs_sel);
#ifdef CONFIG_X86_64
wrmsrl(MSR_GS_BASE, vmcs_readl(HOST_GS_BASE));
load_gs_index(vmx->host_state.gs_sel);
wrmsrl(MSR_KERNEL_GS_BASE, current->thread.gs);
#else
loadsegment(gs, vmx->host_state.gs_sel);
#endif
local_irq_restore(flags);
}
reload_tss();
#ifdef CONFIG_X86_64
@ -2589,8 +2583,8 @@ static int vmx_vcpu_setup(struct vcpu_vmx *vmx)
vmcs_write16(HOST_CS_SELECTOR, __KERNEL_CS); /* 22.2.4 */
vmcs_write16(HOST_DS_SELECTOR, __KERNEL_DS); /* 22.2.4 */
vmcs_write16(HOST_ES_SELECTOR, __KERNEL_DS); /* 22.2.4 */
vmcs_write16(HOST_FS_SELECTOR, kvm_read_fs()); /* 22.2.4 */
vmcs_write16(HOST_GS_SELECTOR, kvm_read_gs()); /* 22.2.4 */
vmcs_write16(HOST_FS_SELECTOR, 0); /* 22.2.4 */
vmcs_write16(HOST_GS_SELECTOR, 0); /* 22.2.4 */
vmcs_write16(HOST_SS_SELECTOR, __KERNEL_DS); /* 22.2.4 */
#ifdef CONFIG_X86_64
rdmsrl(MSR_FS_BASE, a);