d/freebsd-skq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Invalidate guest TLB mappings as a side-effect of its CR3 being updated.

Browse Source 
This is a pre-requisite for task switch emulation since the CR3 is loaded
from the new TSS.
This commit is contained in:
Neel Natu 2014-07-08 20:51:03 +00:00
parent 3120a49e50
commit 3527963b26
1 changed files with 68 additions and 27 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

95
sys/amd64/vmm/intel/vmx.c
View File

@ -974,7 +974,7 @@ vmx_vminit(struct vm *vm, pmap_t pmap)
vmx->cap[i].proc_ctls = procbased_ctls;
vmx->cap[i].proc_ctls2 = procbased_ctls2;
vmx->state[i].lastcpu = -1;
vmx->state[i].lastcpu = NOCPU;
vmx->state[i].vpid = vpid[i];
msr_save_area_init(vmx->guest_msrs[i], &guest_msr_count);
@ -1047,27 +1047,37 @@ vmx_astpending_trace(struct vmx *vmx, int vcpu, uint64_t rip)
}
static VMM_STAT_INTEL(VCPU_INVVPID_SAVED, "Number of vpid invalidations saved");
static VMM_STAT_INTEL(VCPU_INVVPID_DONE, "Number of vpid invalidations done");
static void
vmx_set_pcpu_defaults(struct vmx *vmx, int vcpu, pmap_t pmap)
/*
* Invalidate guest mappings identified by its vpid from the TLB.
*/
static __inline void
vmx_invvpid(struct vmx *vmx, int vcpu, pmap_t pmap, int running)
{
struct vmxstate *vmxstate;
struct invvpid_desc invvpid_desc;
vmxstate = &vmx->state[vcpu];
if (vmxstate->lastcpu == curcpu)
if (vmxstate->vpid == 0)
return;
vmxstate->lastcpu = curcpu;
if (!running) {
/*
* Set the 'lastcpu' to an invalid host cpu.
*
* This will invalidate TLB entries tagged with the vcpu's
* vpid the next time it runs via vmx_set_pcpu_defaults().
*/
vmxstate->lastcpu = NOCPU;
return;
}
vmm_stat_incr(vmx->vm, vcpu, VCPU_MIGRATIONS, 1);
vmcs_write(VMCS_HOST_TR_BASE, vmm_get_host_trbase());
vmcs_write(VMCS_HOST_GDTR_BASE, vmm_get_host_gdtrbase());
vmcs_write(VMCS_HOST_GS_BASE, vmm_get_host_gsbase());
KASSERT(curthread->td_critnest > 0, ("%s: vcpu %d running outside "
"critical section", __func__, vcpu));
/*
* If we are using VPIDs then invalidate all mappings tagged with 'vpid'
* Invalidate all mappings tagged with 'vpid'
*
* We do this because this vcpu was executing on a different host
* cpu when it last ran. We do not track whether it invalidated
@ -1081,25 +1091,43 @@ vmx_set_pcpu_defaults(struct vmx *vmx, int vcpu, pmap_t pmap)
* Note also that this will invalidate mappings tagged with 'vpid'
* for "all" EP4TAs.
*/
if (vmxstate->vpid != 0) {
if (pmap->pm_eptgen == vmx->eptgen[curcpu]) {
invvpid_desc._res1 = 0;
invvpid_desc._res2 = 0;
invvpid_desc.vpid = vmxstate->vpid;
invvpid_desc.linear_addr = 0;
invvpid(INVVPID_TYPE_SINGLE_CONTEXT, invvpid_desc);
} else {
/*
* The invvpid can be skipped if an invept is going to
* be performed before entering the guest. The invept
* will invalidate combined mappings tagged with
* 'vmx->eptp' for all vpids.
*/
vmm_stat_incr(vmx->vm, vcpu, VCPU_INVVPID_SAVED, 1);
}
if (pmap->pm_eptgen == vmx->eptgen[curcpu]) {
invvpid_desc._res1 = 0;
invvpid_desc._res2 = 0;
invvpid_desc.vpid = vmxstate->vpid;
invvpid_desc.linear_addr = 0;
invvpid(INVVPID_TYPE_SINGLE_CONTEXT, invvpid_desc);
vmm_stat_incr(vmx->vm, vcpu, VCPU_INVVPID_DONE, 1);
} else {
/*
* The invvpid can be skipped if an invept is going to
* be performed before entering the guest. The invept
* will invalidate combined mappings tagged with
* 'vmx->eptp' for all vpids.
*/
vmm_stat_incr(vmx->vm, vcpu, VCPU_INVVPID_SAVED, 1);
}
}
static void
vmx_set_pcpu_defaults(struct vmx *vmx, int vcpu, pmap_t pmap)
{
struct vmxstate *vmxstate;
vmxstate = &vmx->state[vcpu];
if (vmxstate->lastcpu == curcpu)
return;
vmxstate->lastcpu = curcpu;
vmm_stat_incr(vmx->vm, vcpu, VCPU_MIGRATIONS, 1);
vmcs_write(VMCS_HOST_TR_BASE, vmm_get_host_trbase());
vmcs_write(VMCS_HOST_GDTR_BASE, vmm_get_host_gdtrbase());
vmcs_write(VMCS_HOST_GS_BASE, vmm_get_host_gsbase());
vmx_invvpid(vmx, vcpu, pmap, 1);
}
/*
* We depend on 'procbased_ctls' to have the Interrupt Window Exiting bit set.
*/
@ -2584,6 +2612,7 @@ vmx_setreg(void *arg, int vcpu, int reg, uint64_t val)
{
int error, hostcpu, running, shadow;
uint64_t ctls;
pmap_t pmap;
struct vmx *vmx = arg;
running = vcpu_is_running(vmx->vm, vcpu, &hostcpu);
@ -2621,6 +2650,18 @@ vmx_setreg(void *arg, int vcpu, int reg, uint64_t val)
error = vmcs_setreg(&vmx->vmcs[vcpu], running,
VMCS_IDENT(shadow), val);
}
if (reg == VM_REG_GUEST_CR3) {
/*
* Invalidate the guest vcpu's TLB mappings to emulate
* the behavior of updating %cr3.
*
* XXX the processor retains global mappings when %cr3
* is updated but vmx_invvpid() does not.
*/
pmap = vmx->ctx[vcpu].pmap;
vmx_invvpid(vmx, vcpu, pmap, running);
}
}
return (error);