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KVM: x86/xen: Add runstate tests for 32-bit mode and crossing page boundary

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Torture test the cases where the runstate crosses a page boundary, and
and especially the case where it's configured in 32-bit mode and doesn't,
but then switching to 64-bit mode makes it go onto the second page.

To simplify this, make the KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_ADJUST ioctl
also update the guest runstate area. It already did so if the actual
runstate changed, as a side-effect of kvm_xen_update_runstate(). So
doing it in the plain adjustment case is making it more consistent, as
well as giving us a nice way to trigger the update without actually
running the vCPU again and changing the values.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
David Woodhouse 2022-11-19 09:27:46 +00:00 committed by Paolo Bonzini
parent d8ba8ba4c8
commit 8acc35186e
2 changed files with 96 additions and 19 deletions
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2
arch/x86/kvm/xen.c
View file

@ -884,6 +884,8 @@ int kvm_xen_vcpu_set_attr(struct kvm_vcpu *vcpu, struct kvm_xen_vcpu_attr *data)
if (data->u.runstate.state <= RUNSTATE_offline)
kvm_xen_update_runstate(vcpu, data->u.runstate.state);
else if (vcpu->arch.xen.runstate_cache.active)
kvm_xen_update_runstate_guest(vcpu, false);
r = 0;
break;

113
tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c
View file

@ -88,14 +88,20 @@ struct pvclock_wall_clock {
} __attribute__((__packed__));
struct vcpu_runstate_info {
uint32_t state;
uint64_t state_entry_time;
uint64_t time[4];
uint32_t state;
uint64_t state_entry_time;
uint64_t time[5]; /* Extra field for overrun check */
};
struct compat_vcpu_runstate_info {
uint32_t state;
uint64_t state_entry_time;
uint64_t time[5];
} __attribute__((__packed__));;
struct arch_vcpu_info {
unsigned long cr2;
unsigned long pad; /* sizeof(vcpu_info_t) == 64 */
unsigned long cr2;
unsigned long pad; /* sizeof(vcpu_info_t) == 64 */
};
struct vcpu_info {
@ -1013,22 +1019,91 @@ int main(int argc, char *argv[])
runstate_names[i], rs->time[i]);
}
}
TEST_ASSERT(rs->state == rst.u.runstate.state, "Runstate mismatch");
TEST_ASSERT(rs->state_entry_time == rst.u.runstate.state_entry_time,
"State entry time mismatch");
TEST_ASSERT(rs->time[RUNSTATE_running] == rst.u.runstate.time_running,
"Running time mismatch");
TEST_ASSERT(rs->time[RUNSTATE_runnable] == rst.u.runstate.time_runnable,
"Runnable time mismatch");
TEST_ASSERT(rs->time[RUNSTATE_blocked] == rst.u.runstate.time_blocked,
"Blocked time mismatch");
TEST_ASSERT(rs->time[RUNSTATE_offline] == rst.u.runstate.time_offline,
"Offline time mismatch");
TEST_ASSERT(rs->state_entry_time == rs->time[0] +
rs->time[1] + rs->time[2] + rs->time[3],
"runstate times don't add up");
/*
* Exercise runstate info at all points across the page boundary, in
* 32-bit and 64-bit mode. In particular, test the case where it is
* configured in 32-bit mode and then switched to 64-bit mode while
* active, which takes it onto the second page.
*/
unsigned long runstate_addr;
struct compat_vcpu_runstate_info *crs;
for (runstate_addr = SHINFO_REGION_GPA + PAGE_SIZE + PAGE_SIZE - sizeof(*rs) - 4;
runstate_addr < SHINFO_REGION_GPA + PAGE_SIZE + PAGE_SIZE + 4; runstate_addr++) {
rs = addr_gpa2hva(vm, runstate_addr);
crs = (void *)rs;
memset(rs, 0xa5, sizeof(*rs));
/* Set to compatibility mode */
lm.u.long_mode = 0;
vm_ioctl(vm, KVM_XEN_HVM_SET_ATTR, &lm);
/* Set runstate to new address (kernel will write it) */
struct kvm_xen_vcpu_attr st = {
.type = KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_ADDR,
.u.gpa = runstate_addr,
};
vcpu_ioctl(vcpu, KVM_XEN_VCPU_SET_ATTR, &st);
if (verbose)
printf("Compatibility runstate at %08lx\n", runstate_addr);
TEST_ASSERT(crs->state == rst.u.runstate.state, "Runstate mismatch");
TEST_ASSERT(crs->state_entry_time == rst.u.runstate.state_entry_time,
"State entry time mismatch");
TEST_ASSERT(crs->time[RUNSTATE_running] == rst.u.runstate.time_running,
"Running time mismatch");
TEST_ASSERT(crs->time[RUNSTATE_runnable] == rst.u.runstate.time_runnable,
"Runnable time mismatch");
TEST_ASSERT(crs->time[RUNSTATE_blocked] == rst.u.runstate.time_blocked,
"Blocked time mismatch");
TEST_ASSERT(crs->time[RUNSTATE_offline] == rst.u.runstate.time_offline,
"Offline time mismatch");
TEST_ASSERT(crs->time[RUNSTATE_offline + 1] == 0xa5a5a5a5a5a5a5a5ULL,
"Structure overrun");
TEST_ASSERT(crs->state_entry_time == crs->time[0] +
crs->time[1] + crs->time[2] + crs->time[3],
"runstate times don't add up");
/* Now switch to 64-bit mode */
lm.u.long_mode = 1;
vm_ioctl(vm, KVM_XEN_HVM_SET_ATTR, &lm);
memset(rs, 0xa5, sizeof(*rs));
/* Don't change the address, just trigger a write */
struct kvm_xen_vcpu_attr adj = {
.type = KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_ADJUST,
.u.runstate.state = (uint64_t)-1
};
vcpu_ioctl(vcpu, KVM_XEN_VCPU_SET_ATTR, &adj);
if (verbose)
printf("64-bit runstate at %08lx\n", runstate_addr);
TEST_ASSERT(rs->state == rst.u.runstate.state, "Runstate mismatch");
TEST_ASSERT(rs->state_entry_time == rst.u.runstate.state_entry_time,
"State entry time mismatch");
TEST_ASSERT(rs->time[RUNSTATE_running] == rst.u.runstate.time_running,
"Running time mismatch");
TEST_ASSERT(rs->time[RUNSTATE_runnable] == rst.u.runstate.time_runnable,
"Runnable time mismatch");
TEST_ASSERT(rs->time[RUNSTATE_blocked] == rst.u.runstate.time_blocked,
"Blocked time mismatch");
TEST_ASSERT(rs->time[RUNSTATE_offline] == rst.u.runstate.time_offline,
"Offline time mismatch");
TEST_ASSERT(rs->time[RUNSTATE_offline + 1] == 0xa5a5a5a5a5a5a5a5ULL,
"Structure overrun");
TEST_ASSERT(rs->state_entry_time == rs->time[0] +
rs->time[1] + rs->time[2] + rs->time[3],
"runstate times don't add up");
}
}
kvm_vm_free(vm);
return 0;
}