| Message ID | 584986dc-eeb6-4cfe-8ee3-330b17c55c09@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi On Mon, Jan 22, 2018 at 12:53 PM, Michal Privoznik <mprivozn@redhat.com> wrote: > On 01/14/2018 11:06 AM, Gal Hammer wrote: >> Use the EventNotifier's cleanup callback function to execute the >> event_notifier_cleanup function after kvm unregistered the eventfd. >> >> This change supports running the virtio_bus_set_host_notifier >> function inside a memory region transaction. Otherwise, a closed >> fd is sent to kvm, which results in a failure. >> >> Signed-off-by: Gal Hammer <ghammer@redhat.com> >> --- >> accel/kvm/kvm-all.c | 4 ++++ >> hw/virtio/virtio-bus.c | 19 +++++++++++-------- >> 2 files changed, 15 insertions(+), 8 deletions(-) >> >> diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c >> index f290f48..071f4f5 100644 >> --- a/accel/kvm/kvm-all.c >> +++ b/accel/kvm/kvm-all.c >> @@ -812,6 +812,10 @@ static void kvm_mem_ioeventfd_del(MemoryListener *listener, >> if (r < 0) { >> abort(); >> } >> + >> + if (e->cleanup) { >> + e->cleanup(e); >> + } >> } >> >> static void kvm_io_ioeventfd_add(MemoryListener *listener, >> diff --git a/hw/virtio/virtio-bus.c b/hw/virtio/virtio-bus.c >> index 3042232..8106346 100644 >> --- a/hw/virtio/virtio-bus.c >> +++ b/hw/virtio/virtio-bus.c >> @@ -256,6 +256,15 @@ bool virtio_bus_ioeventfd_enabled(VirtioBusState *bus) >> return k->ioeventfd_assign && k->ioeventfd_enabled(proxy); >> } >> >> +static void virtio_bus_cleanup_event_notifier(EventNotifier *notifier) >> +{ >> + /* Test and clear notifier after disabling event, >> + * in case poll callback didn't have time to run. >> + */ >> + virtio_queue_host_notifier_read(notifier); >> + event_notifier_cleanup(notifier); >> +} >> + >> /* >> * This function switches ioeventfd on/off in the device. >> * The caller must set or clear the handlers for the EventNotifier. >> @@ -283,19 +292,13 @@ int virtio_bus_set_host_notifier(VirtioBusState *bus, int n, bool assign) >> r = k->ioeventfd_assign(proxy, notifier, n, true); >> if (r < 0) { >> error_report("%s: unable to assign ioeventfd: %d", __func__, r); >> - goto cleanup_event_notifier; >> + virtio_bus_cleanup_event_notifier(notifier); >> } >> - return 0; >> } else { >> + notifier->cleanup = virtio_bus_cleanup_event_notifier; >> k->ioeventfd_assign(proxy, notifier, n, false); >> } >> >> -cleanup_event_notifier: >> - /* Test and clear notifier after disabling event, >> - * in case poll callback didn't have time to run. >> - */ >> - virtio_queue_host_notifier_read(notifier); >> - event_notifier_cleanup(notifier); >> return r; >> } >> >> > > This causes abort() to me: > > Thread 7 "CPU 3/KVM" received signal SIGABRT, Aborted. > [Switching to Thread 0x7f78fa1f4700 (LWP 13737)] > __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:51 > 51 } > __GI_raise 7 # bt > #0 __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:51 > #1 0x00007f7a09ff5c1a in __GI_abort () at abort.c:89 > #2 0x000055f2a70bce9d in kvm_io_ioeventfd_del (listener=0x55f2a7d19200 <kvm_io_listener>, section=0x7f78fa1f10f0, match_data=true, data=0, e=0x7f79fc81f080) at /home/zippy/work/qemu/qemu.git/accel/kvm/kvm-all.c:852 > #3 0x000055f2a70a6fac in address_space_add_del_ioeventfds (as=0x55f2a7e86620 <address_space_io>, fds_new=0x7f78e40b9e80, fds_new_nb=2, fds_old=0x7f78e40b9f10, fds_old_nb=3) at /home/zippy/work/qemu/qemu.git/memory.c:832 > #4 0x000055f2a70a744d in address_space_update_ioeventfds (as=0x55f2a7e86620 <address_space_io>) at /home/zippy/work/qemu/qemu.git/memory.c:895 > #5 0x000055f2a70a7f04 in memory_region_transaction_commit () at /home/zippy/work/qemu/qemu.git/memory.c:1097 > #6 0x000055f2a70ab0d1 in memory_region_del_eventfd (mr=0x55f2a9422250, addr=16, size=2, match_data=true, data=0, e=0x7f79fc81f080) at /home/zippy/work/qemu/qemu.git/memory.c:2273 > #7 0x000055f2a7411f18 in virtio_pci_ioeventfd_assign (d=0x55f2a9421970, notifier=0x7f79fc81f080, n=0, assign=false) at hw/virtio/virtio-pci.c:280 > #8 0x000055f2a7418e6f in virtio_bus_set_host_notifier (bus=0x55f2a9429a68, n=0, assign=false) at hw/virtio/virtio-bus.c:299 > #9 0x000055f2a710236a in virtio_scsi_dataplane_stop (vdev=0x55f2a9429ae0) at /home/zippy/work/qemu/qemu.git/hw/scsi/virtio-scsi-dataplane.c:215 > #10 0x000055f2a7418bb3 in virtio_bus_stop_ioeventfd (bus=0x55f2a9429a68) at hw/virtio/virtio-bus.c:246 > #11 0x000055f2a7411f63 in virtio_pci_stop_ioeventfd (proxy=0x55f2a9421970) at hw/virtio/virtio-pci.c:294 > #12 0x000055f2a74144ab in virtio_pci_common_write (opaque=0x55f2a9421970, addr=20, val=0, size=1) at hw/virtio/virtio-pci.c:1262 > #13 0x000055f2a70a6016 in memory_region_write_accessor (mr=0x55f2a9422340, addr=20, value=0x7f78fa1f1558, size=1, shift=0, mask=255, attrs=...) at /home/zippy/work/qemu/qemu.git/memory.c:560 > #14 0x000055f2a70a622e in access_with_adjusted_size (addr=20, value=0x7f78fa1f1558, size=1, access_size_min=1, access_size_max=4, access_fn=0x55f2a70a5f2c <memory_region_write_accessor>, mr=0x55f2a9422340, attrs=...) at /home/zippy/work/qemu/qemu.git/memory.c:627 > #15 0x000055f2a70a8eb0 in memory_region_dispatch_write (mr=0x55f2a9422340, addr=20, data=0, size=1, attrs=...) at /home/zippy/work/qemu/qemu.git/memory.c:1503 > #16 0x000055f2a7058b2b in flatview_write_continue (fv=0x7f78e405eba0, addr=4269834260, attrs=..., buf=0x7f7a26c36028 "", len=1, addr1=20, l=1, mr=0x55f2a9422340) at /home/zippy/work/qemu/qemu.git/exec.c:3038 > #17 0x000055f2a7058c79 in flatview_write (fv=0x7f78e405eba0, addr=4269834260, attrs=..., buf=0x7f7a26c36028 "", len=1) at /home/zippy/work/qemu/qemu.git/exec.c:3083 > #18 0x000055f2a7059050 in flatview_rw (fv=0x7f78e405eba0, addr=4269834260, attrs=..., buf=0x7f7a26c36028 "", len=1, is_write=true) at /home/zippy/work/qemu/qemu.git/exec.c:3192 > #19 0x000055f2a7059108 in address_space_rw (as=0x55f2a7e86680 <address_space_memory>, addr=4269834260, attrs=..., buf=0x7f7a26c36028 "", len=1, is_write=true) at /home/zippy/work/qemu/qemu.git/exec.c:3202 > #20 0x000055f2a70bf42c in kvm_cpu_exec (cpu=0x55f2a850cda0) at /home/zippy/work/qemu/qemu.git/accel/kvm/kvm-all.c:1941 > #21 0x000055f2a708d455 in qemu_kvm_cpu_thread_fn (arg=0x55f2a850cda0) at /home/zippy/work/qemu/qemu.git/cpus.c:1196 > #22 0x000055f2a75ce829 in qemu_thread_start (args=0x55f2a852e260) at util/qemu-thread-posix.c:504 > #23 0x00007f7a0a375887 in start_thread (arg=0x7f78fa1f4700) at pthread_create.c:456 > #24 0x00007f7a0a0b7d4f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:97 > __GI_raise 7 # up > #1 0x00007f7a09ff5c1a in __GI_abort () at abort.c:89 > 89 raise (SIGABRT); > __GI_abort 7 # > #2 0x000055f2a70bce9d in kvm_io_ioeventfd_del (listener=0x55f2a7d19200 <kvm_io_listener>, section=0x7f78fa1f10f0, match_data=true, data=0, e=0x7f79fc81f080) at /home/zippy/work/qemu/qemu.git/accel/kvm/kvm-all.c:852 > 852 abort(); > kvm_io_ioeventfd_del 7 # p *e > $1 = {rfd = -1, wfd = -1, cleanup = 0x0} > > > I think the problem is that event_notifier_cleanup() is called before > kvm_io_ioeventfd_del() and both are called over the same EventNotifier. > This is supported by another data I was able to collect in a different > run: > > Thread 4 "CPU 0/KVM" hit Breakpoint 1, event_notifier_cleanup (e=0x7fc6ac26f080) at util/event_notifier-posix.c:83 > 83 if (e->rfd != e->wfd) { > event_notifier_cleanup 4 # p *e > $1 = {rfd = 48, wfd = 48, cleanup = 0x55c91c76ac87 <virtio_bus_cleanup_event_notifier>} > event_notifier_cleanup 4 # c > Continuing. > > Thread 4 "CPU 0/KVM" received signal SIGABRT, Aborted. > __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:51 > 51 } > __GI_raise 4 # up > #1 0x00007fc6b9a45c1a in __GI_abort () at abort.c:89 > 89 raise (SIGABRT); > __GI_abort 4 # > #2 0x000055c91c40ee9d in kvm_io_ioeventfd_del (listener=0x55c91d06b200 <kvm_io_listener>, section=0x7fc5ab1fa0f0, match_data=true, data=0, e=0x7fc6ac26f080) at /home/zippy/work/qemu/qemu.git/accel/kvm/kvm-all.c:852 > 852 abort(); > kvm_io_ioeventfd_del 4 # p *e > $2 = {rfd = -1, wfd = -1, cleanup = 0x0} > > > So I drafted dirty workaround: > > index 071f4f57c0..bf15344533 100644 > --- i/accel/kvm/kvm-all.c > +++ w/accel/kvm/kvm-all.c > @@ -845,6 +845,9 @@ static void kvm_io_ioeventfd_del(MemoryListener *listener, > int fd = event_notifier_get_fd(e); > int r; > > + if (fd == -1) > + return; > + > r = kvm_set_ioeventfd_pio(fd, section->offset_within_address_space, > data, false, int128_get64(section->size), > match_data); > > But this time I'm getting following error: > > kvm_io_ioeventfd_add: error adding ioeventfd: File exists > > __GI_raise 7 # up > #1 0x00007f3ccd579c1a in __GI_abort () at abort.c:89 > 89 raise (SIGABRT); > __GI_abort 7 # > #2 0x000055c68ac84e08 in kvm_io_ioeventfd_add (listener=0x55c68b8e1200 <kvm_io_listener>, section=0x7f3bbd7f1090, match_data=true, data=0, e=0x7f3bbcf8d080) at /home/zippy/work/qemu/qemu.git/accel/kvm/kvm-all.c:835 > 835 abort(); > kvm_io_ioeventfd_add 7 # p *e > $1 = {rfd = 48, wfd = 48, cleanup = 0x0} > I was about to report the same error when booting an uefi guest, I bisected down to the same first bad commit. Thanks Michal
On Mon, Jan 22, 2018 at 06:35:03PM +0100, Marc-André Lureau wrote: > Hi > > On Mon, Jan 22, 2018 at 12:53 PM, Michal Privoznik <mprivozn@redhat.com> wrote: > > On 01/14/2018 11:06 AM, Gal Hammer wrote: > >> Use the EventNotifier's cleanup callback function to execute the > >> event_notifier_cleanup function after kvm unregistered the eventfd. > >> > >> This change supports running the virtio_bus_set_host_notifier > >> function inside a memory region transaction. Otherwise, a closed > >> fd is sent to kvm, which results in a failure. > >> > >> Signed-off-by: Gal Hammer <ghammer@redhat.com> > >> --- > >> accel/kvm/kvm-all.c | 4 ++++ > >> hw/virtio/virtio-bus.c | 19 +++++++++++-------- > >> 2 files changed, 15 insertions(+), 8 deletions(-) > >> > >> diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c > >> index f290f48..071f4f5 100644 > >> --- a/accel/kvm/kvm-all.c > >> +++ b/accel/kvm/kvm-all.c > >> @@ -812,6 +812,10 @@ static void kvm_mem_ioeventfd_del(MemoryListener *listener, > >> if (r < 0) { > >> abort(); > >> } > >> + > >> + if (e->cleanup) { > >> + e->cleanup(e); > >> + } > >> } > >> > >> static void kvm_io_ioeventfd_add(MemoryListener *listener, > >> diff --git a/hw/virtio/virtio-bus.c b/hw/virtio/virtio-bus.c > >> index 3042232..8106346 100644 > >> --- a/hw/virtio/virtio-bus.c > >> +++ b/hw/virtio/virtio-bus.c > >> @@ -256,6 +256,15 @@ bool virtio_bus_ioeventfd_enabled(VirtioBusState *bus) > >> return k->ioeventfd_assign && k->ioeventfd_enabled(proxy); > >> } > >> > >> +static void virtio_bus_cleanup_event_notifier(EventNotifier *notifier) > >> +{ > >> + /* Test and clear notifier after disabling event, > >> + * in case poll callback didn't have time to run. > >> + */ > >> + virtio_queue_host_notifier_read(notifier); > >> + event_notifier_cleanup(notifier); > >> +} > >> + > >> /* > >> * This function switches ioeventfd on/off in the device. > >> * The caller must set or clear the handlers for the EventNotifier. > >> @@ -283,19 +292,13 @@ int virtio_bus_set_host_notifier(VirtioBusState *bus, int n, bool assign) > >> r = k->ioeventfd_assign(proxy, notifier, n, true); > >> if (r < 0) { > >> error_report("%s: unable to assign ioeventfd: %d", __func__, r); > >> - goto cleanup_event_notifier; > >> + virtio_bus_cleanup_event_notifier(notifier); > >> } > >> - return 0; > >> } else { > >> + notifier->cleanup = virtio_bus_cleanup_event_notifier; > >> k->ioeventfd_assign(proxy, notifier, n, false); > >> } > >> > >> -cleanup_event_notifier: > >> - /* Test and clear notifier after disabling event, > >> - * in case poll callback didn't have time to run. > >> - */ > >> - virtio_queue_host_notifier_read(notifier); > >> - event_notifier_cleanup(notifier); > >> return r; > >> } > >> > >> > > > > This causes abort() to me: > > > > Thread 7 "CPU 3/KVM" received signal SIGABRT, Aborted. > > [Switching to Thread 0x7f78fa1f4700 (LWP 13737)] > > __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:51 > > 51 } > > __GI_raise 7 # bt > > #0 __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:51 > > #1 0x00007f7a09ff5c1a in __GI_abort () at abort.c:89 > > #2 0x000055f2a70bce9d in kvm_io_ioeventfd_del (listener=0x55f2a7d19200 <kvm_io_listener>, section=0x7f78fa1f10f0, match_data=true, data=0, e=0x7f79fc81f080) at /home/zippy/work/qemu/qemu.git/accel/kvm/kvm-all.c:852 > > #3 0x000055f2a70a6fac in address_space_add_del_ioeventfds (as=0x55f2a7e86620 <address_space_io>, fds_new=0x7f78e40b9e80, fds_new_nb=2, fds_old=0x7f78e40b9f10, fds_old_nb=3) at /home/zippy/work/qemu/qemu.git/memory.c:832 > > #4 0x000055f2a70a744d in address_space_update_ioeventfds (as=0x55f2a7e86620 <address_space_io>) at /home/zippy/work/qemu/qemu.git/memory.c:895 > > #5 0x000055f2a70a7f04 in memory_region_transaction_commit () at /home/zippy/work/qemu/qemu.git/memory.c:1097 > > #6 0x000055f2a70ab0d1 in memory_region_del_eventfd (mr=0x55f2a9422250, addr=16, size=2, match_data=true, data=0, e=0x7f79fc81f080) at /home/zippy/work/qemu/qemu.git/memory.c:2273 > > #7 0x000055f2a7411f18 in virtio_pci_ioeventfd_assign (d=0x55f2a9421970, notifier=0x7f79fc81f080, n=0, assign=false) at hw/virtio/virtio-pci.c:280 > > #8 0x000055f2a7418e6f in virtio_bus_set_host_notifier (bus=0x55f2a9429a68, n=0, assign=false) at hw/virtio/virtio-bus.c:299 > > #9 0x000055f2a710236a in virtio_scsi_dataplane_stop (vdev=0x55f2a9429ae0) at /home/zippy/work/qemu/qemu.git/hw/scsi/virtio-scsi-dataplane.c:215 > > #10 0x000055f2a7418bb3 in virtio_bus_stop_ioeventfd (bus=0x55f2a9429a68) at hw/virtio/virtio-bus.c:246 > > #11 0x000055f2a7411f63 in virtio_pci_stop_ioeventfd (proxy=0x55f2a9421970) at hw/virtio/virtio-pci.c:294 > > #12 0x000055f2a74144ab in virtio_pci_common_write (opaque=0x55f2a9421970, addr=20, val=0, size=1) at hw/virtio/virtio-pci.c:1262 > > #13 0x000055f2a70a6016 in memory_region_write_accessor (mr=0x55f2a9422340, addr=20, value=0x7f78fa1f1558, size=1, shift=0, mask=255, attrs=...) at /home/zippy/work/qemu/qemu.git/memory.c:560 > > #14 0x000055f2a70a622e in access_with_adjusted_size (addr=20, value=0x7f78fa1f1558, size=1, access_size_min=1, access_size_max=4, access_fn=0x55f2a70a5f2c <memory_region_write_accessor>, mr=0x55f2a9422340, attrs=...) at /home/zippy/work/qemu/qemu.git/memory.c:627 > > #15 0x000055f2a70a8eb0 in memory_region_dispatch_write (mr=0x55f2a9422340, addr=20, data=0, size=1, attrs=...) at /home/zippy/work/qemu/qemu.git/memory.c:1503 > > #16 0x000055f2a7058b2b in flatview_write_continue (fv=0x7f78e405eba0, addr=4269834260, attrs=..., buf=0x7f7a26c36028 "", len=1, addr1=20, l=1, mr=0x55f2a9422340) at /home/zippy/work/qemu/qemu.git/exec.c:3038 > > #17 0x000055f2a7058c79 in flatview_write (fv=0x7f78e405eba0, addr=4269834260, attrs=..., buf=0x7f7a26c36028 "", len=1) at /home/zippy/work/qemu/qemu.git/exec.c:3083 > > #18 0x000055f2a7059050 in flatview_rw (fv=0x7f78e405eba0, addr=4269834260, attrs=..., buf=0x7f7a26c36028 "", len=1, is_write=true) at /home/zippy/work/qemu/qemu.git/exec.c:3192 > > #19 0x000055f2a7059108 in address_space_rw (as=0x55f2a7e86680 <address_space_memory>, addr=4269834260, attrs=..., buf=0x7f7a26c36028 "", len=1, is_write=true) at /home/zippy/work/qemu/qemu.git/exec.c:3202 > > #20 0x000055f2a70bf42c in kvm_cpu_exec (cpu=0x55f2a850cda0) at /home/zippy/work/qemu/qemu.git/accel/kvm/kvm-all.c:1941 > > #21 0x000055f2a708d455 in qemu_kvm_cpu_thread_fn (arg=0x55f2a850cda0) at /home/zippy/work/qemu/qemu.git/cpus.c:1196 > > #22 0x000055f2a75ce829 in qemu_thread_start (args=0x55f2a852e260) at util/qemu-thread-posix.c:504 > > #23 0x00007f7a0a375887 in start_thread (arg=0x7f78fa1f4700) at pthread_create.c:456 > > #24 0x00007f7a0a0b7d4f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:97 > > __GI_raise 7 # up > > #1 0x00007f7a09ff5c1a in __GI_abort () at abort.c:89 > > 89 raise (SIGABRT); > > __GI_abort 7 # > > #2 0x000055f2a70bce9d in kvm_io_ioeventfd_del (listener=0x55f2a7d19200 <kvm_io_listener>, section=0x7f78fa1f10f0, match_data=true, data=0, e=0x7f79fc81f080) at /home/zippy/work/qemu/qemu.git/accel/kvm/kvm-all.c:852 > > 852 abort(); > > kvm_io_ioeventfd_del 7 # p *e > > $1 = {rfd = -1, wfd = -1, cleanup = 0x0} > > > > > > I think the problem is that event_notifier_cleanup() is called before > > kvm_io_ioeventfd_del() and both are called over the same EventNotifier. > > This is supported by another data I was able to collect in a different > > run: > > > > Thread 4 "CPU 0/KVM" hit Breakpoint 1, event_notifier_cleanup (e=0x7fc6ac26f080) at util/event_notifier-posix.c:83 > > 83 if (e->rfd != e->wfd) { > > event_notifier_cleanup 4 # p *e > > $1 = {rfd = 48, wfd = 48, cleanup = 0x55c91c76ac87 <virtio_bus_cleanup_event_notifier>} > > event_notifier_cleanup 4 # c > > Continuing. > > > > Thread 4 "CPU 0/KVM" received signal SIGABRT, Aborted. > > __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:51 > > 51 } > > __GI_raise 4 # up > > #1 0x00007fc6b9a45c1a in __GI_abort () at abort.c:89 > > 89 raise (SIGABRT); > > __GI_abort 4 # > > #2 0x000055c91c40ee9d in kvm_io_ioeventfd_del (listener=0x55c91d06b200 <kvm_io_listener>, section=0x7fc5ab1fa0f0, match_data=true, data=0, e=0x7fc6ac26f080) at /home/zippy/work/qemu/qemu.git/accel/kvm/kvm-all.c:852 > > 852 abort(); > > kvm_io_ioeventfd_del 4 # p *e > > $2 = {rfd = -1, wfd = -1, cleanup = 0x0} > > > > > > So I drafted dirty workaround: > > > > index 071f4f57c0..bf15344533 100644 > > --- i/accel/kvm/kvm-all.c > > +++ w/accel/kvm/kvm-all.c > > @@ -845,6 +845,9 @@ static void kvm_io_ioeventfd_del(MemoryListener *listener, > > int fd = event_notifier_get_fd(e); > > int r; > > > > + if (fd == -1) > > + return; > > + > > r = kvm_set_ioeventfd_pio(fd, section->offset_within_address_space, > > data, false, int128_get64(section->size), > > match_data); > > > > But this time I'm getting following error: > > > > kvm_io_ioeventfd_add: error adding ioeventfd: File exists > > > > __GI_raise 7 # up > > #1 0x00007f3ccd579c1a in __GI_abort () at abort.c:89 > > 89 raise (SIGABRT); > > __GI_abort 7 # > > #2 0x000055c68ac84e08 in kvm_io_ioeventfd_add (listener=0x55c68b8e1200 <kvm_io_listener>, section=0x7f3bbd7f1090, match_data=true, data=0, e=0x7f3bbcf8d080) at /home/zippy/work/qemu/qemu.git/accel/kvm/kvm-all.c:835 > > 835 abort(); > > kvm_io_ioeventfd_add 7 # p *e > > $1 = {rfd = 48, wfd = 48, cleanup = 0x0} > > > > I was about to report the same error when booting an uefi guest, I > bisected down to the same first bad commit. > > Thanks Michal Gal - any input on this before I revert? > -- > Marc-André Lureau
--- i/accel/kvm/kvm-all.c +++ w/accel/kvm/kvm-all.c @@ -845,6 +845,9 @@ static void kvm_io_ioeventfd_del(MemoryListener *listener, int fd = event_notifier_get_fd(e); int r; + if (fd == -1) + return; + r = kvm_set_ioeventfd_pio(fd, section->offset_within_address_space, data, false, int128_get64(section->size), match_data);