diff options
author | David Woodhouse <dwmw@amazon.co.uk> | 2023-02-04 05:41:51 +0300 |
---|---|---|
committer | Paolo Bonzini <pbonzini@redhat.com> | 2023-03-14 17:20:08 +0300 |
commit | e6239a4ec5c51e4d5ee4d1604f741f490c32054c (patch) | |
tree | 7a938b31a8d62e27d312036c55cc870cfc49755d | |
parent | e7062a98d0b3e0b42089f4c5da633a1ce41b807f (diff) | |
download | linux-e6239a4ec5c51e4d5ee4d1604f741f490c32054c.tar.xz |
KVM: selftests: Add EVTCHNOP_send slow path test to xen_shinfo_test
When kvm_xen_evtchn_send() takes the slow path because the shinfo GPC
needs to be revalidated, it used to violate the SRCU vs. kvm->lock
locking rules and potentially cause a deadlock.
Now that lockdep is learning to catch such things, make sure that code
path is exercised by the selftest.
Link: https://lore.kernel.org/all/20230113124606.10221-2-dwmw2@infradead.org
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230204024151.1373296-5-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
-rw-r--r-- | tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c b/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c index 1a3d2d51fef0..d42701dfbd83 100644 --- a/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c +++ b/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c @@ -26,6 +26,9 @@ #define DUMMY_REGION_GPA (SHINFO_REGION_GPA + (3 * PAGE_SIZE)) #define DUMMY_REGION_SLOT 11 +#define DUMMY_REGION_GPA_2 (SHINFO_REGION_GPA + (4 * PAGE_SIZE)) +#define DUMMY_REGION_SLOT_2 12 + #define SHINFO_ADDR (SHINFO_REGION_GPA) #define VCPU_INFO_ADDR (SHINFO_REGION_GPA + 0x40) #define PVTIME_ADDR (SHINFO_REGION_GPA + PAGE_SIZE) @@ -54,6 +57,7 @@ enum { TEST_EVTCHN_SLOWPATH, TEST_EVTCHN_SEND_IOCTL, TEST_EVTCHN_HCALL, + TEST_EVTCHN_HCALL_SLOWPATH, TEST_EVTCHN_HCALL_EVENTFD, TEST_TIMER_SETUP, TEST_TIMER_WAIT, @@ -260,6 +264,16 @@ static void guest_code(void) guest_wait_for_irq(); + GUEST_SYNC(TEST_EVTCHN_HCALL_SLOWPATH); + + /* + * Same again, but this time the host has messed with memslots so it + * should take the slow path in kvm_xen_set_evtchn(). + */ + xen_hypercall(__HYPERVISOR_event_channel_op, EVTCHNOP_send, &s); + + guest_wait_for_irq(); + GUEST_SYNC(TEST_EVTCHN_HCALL_EVENTFD); /* Deliver "outbound" event channel to an eventfd which @@ -753,6 +767,19 @@ int main(int argc, char *argv[]) alarm(1); break; + case TEST_EVTCHN_HCALL_SLOWPATH: + TEST_ASSERT(!evtchn_irq_expected, + "Expected event channel IRQ but it didn't happen"); + shinfo->evtchn_pending[0] = 0; + + if (verbose) + printf("Testing guest EVTCHNOP_send direct to evtchn after memslot change\n"); + vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, + DUMMY_REGION_GPA_2, DUMMY_REGION_SLOT_2, 1, 0); + evtchn_irq_expected = true; + alarm(1); + break; + case TEST_EVTCHN_HCALL_EVENTFD: TEST_ASSERT(!evtchn_irq_expected, "Expected event channel IRQ but it didn't happen"); |