On Wed, Apr 10, 2024 at 1:36 PM Jason Wang <jasow...@redhat.com> wrote: > > On Wed, Apr 10, 2024 at 1:29 PM Cindy Lu <l...@redhat.com> wrote: > > > > When the guest triggers vhost_stop and then virtio_reset, the vector will > > the > > IRQFD for this vector will be released and change to VIRTIO_NO_VECTOR. > > After that, the guest called vhost_net_start, (at this time, the configure > > vector is still VIRTIO_NO_VECTOR), vector 0 still was not "init". > > The guest system continued to boot, set the vector back to 0, and then met > > the crash. > > > > To fix this, we need to call the function "kvm_virtio_pci_vector_use_one()" > > when the vector changes back from VIRTIO_NO_VECTOR > > > > (gdb) bt > > 0 __pthread_kill_implementation (threadid=<optimized out>, > > signo=signo@entry=6, no_tid=no_tid@entry=0) > > at pthread_kill.c:44 > > 1 0x00007fc87148ec53 in __pthread_kill_internal (signo=6, > > threadid=<optimized out>) at pthread_kill.c:78 > > 2 0x00007fc87143e956 in __GI_raise (sig=sig@entry=6) at > > ../sysdeps/posix/raise.c:26 > > 3 0x00007fc8714287f4 in __GI_abort () at abort.c:79 > > 4 0x00007fc87142871b in __assert_fail_base > > (fmt=0x7fc8715bbde0 "%s%s%s:%u: %s%sAssertion `%s' failed.\n%n", > > assertion=0x5606413efd53 "ret == 0", file=0x5606413ef87d > > "../accel/kvm/kvm-all.c", line=1837, function=<optimized out>) at > > assert.c:92 > > 5 0x00007fc871437536 in __GI___assert_fail > > (assertion=0x5606413efd53 "ret == 0", file=0x5606413ef87d > > "../accel/kvm/kvm-all.c", line=1837, function=0x5606413f06f0 > > <__PRETTY_FUNCTION__.19> "kvm_irqchip_commit_routes") at assert.c:101 > > 6 0x0000560640f884b5 in kvm_irqchip_commit_routes (s=0x560642cae1f0) at > > ../accel/kvm/kvm-all.c:1837 > > 7 0x0000560640c98f8e in virtio_pci_one_vector_unmask > > (proxy=0x560643c65f00, queue_no=4294967295, vector=0, msg=..., > > n=0x560643c6e4c8) > > at ../hw/virtio/virtio-pci.c:1005 > > 8 0x0000560640c99201 in virtio_pci_vector_unmask (dev=0x560643c65f00, > > vector=0, msg=...) > > at ../hw/virtio/virtio-pci.c:1070 > > 9 0x0000560640bc402e in msix_fire_vector_notifier (dev=0x560643c65f00, > > vector=0, is_masked=false) > > at ../hw/pci/msix.c:120 > > 10 0x0000560640bc40f1 in msix_handle_mask_update (dev=0x560643c65f00, > > vector=0, was_masked=true) > > at ../hw/pci/msix.c:140 > > 11 0x0000560640bc4503 in msix_table_mmio_write (opaque=0x560643c65f00, > > addr=12, val=0, size=4) > > at ../hw/pci/msix.c:231 > > 12 0x0000560640f26d83 in memory_region_write_accessor > > (mr=0x560643c66540, addr=12, value=0x7fc86b7bc628, size=4, shift=0, > > mask=4294967295, attrs=...) > > at ../system/memory.c:497 > > 13 0x0000560640f270a6 in access_with_adjusted_size > > > > (addr=12, value=0x7fc86b7bc628, size=4, access_size_min=1, > > access_size_max=4, access_fn=0x560640f26c8d <memory_region_write_accessor>, > > mr=0x560643c66540, attrs=...) at ../system/memory.c:573 > > 14 0x0000560640f2a2b5 in memory_region_dispatch_write (mr=0x560643c66540, > > addr=12, data=0, op=MO_32, attrs=...) > > at ../system/memory.c:1521 > > 15 0x0000560640f37bac in flatview_write_continue > > (fv=0x7fc65805e0b0, addr=4273803276, attrs=..., ptr=0x7fc871e9c028, > > len=4, addr1=12, l=4, mr=0x560643c66540) > > at ../system/physmem.c:2714 > > 16 0x0000560640f37d0f in flatview_write > > (fv=0x7fc65805e0b0, addr=4273803276, attrs=..., buf=0x7fc871e9c028, > > len=4) at ../system/physmem.c:2756 > > 17 0x0000560640f380bf in address_space_write > > (as=0x560642161ae0 <address_space_memory>, addr=4273803276, attrs=..., > > buf=0x7fc871e9c028, len=4) > > at ../system/physmem.c:2863 > > 18 0x0000560640f3812c in address_space_rw > > (as=0x560642161ae0 <address_space_memory>, addr=4273803276, attrs=..., > > buf=0x7fc871e9c028, len=4, is_write=true) at ../system/physmem.c:2873 > > --Type <RET> for more, q to quit, c to continue without paging-- > > 19 0x0000560640f8aa55 in kvm_cpu_exec (cpu=0x560642f205e0) at > > ../accel/kvm/kvm-all.c:2915 > > 20 0x0000560640f8d731 in kvm_vcpu_thread_fn (arg=0x560642f205e0) at > > ../accel/kvm/kvm-accel-ops.c:51 > > 21 0x00005606411949f4 in qemu_thread_start (args=0x560642f292b0) at > > ../util/qemu-thread-posix.c:541 > > 22 0x00007fc87148cdcd in start_thread (arg=<optimized out>) at > > pthread_create.c:442 > > 23 0x00007fc871512630 in clone3 () at > > ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81 > > (gdb) > > Signed-off-by: Cindy Lu <l...@redhat.com> > > --- > > hw/virtio/virtio-pci.c | 35 +++++++++++++++++++++++++++++++++++ > > 1 file changed, 35 insertions(+) > > > > diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c > > index 1a7039fb0c..344f4fb844 100644 > > --- a/hw/virtio/virtio-pci.c > > +++ b/hw/virtio/virtio-pci.c > > @@ -880,6 +880,7 @@ static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy > > *proxy, int queue_no) > > int ret; > > EventNotifier *n; > > PCIDevice *dev = &proxy->pci_dev; > > + VirtIOIRQFD *irqfd; > > VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus); > > VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); > > > > @@ -890,10 +891,19 @@ static int > > kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int queue_no) > > if (vector >= msix_nr_vectors_allocated(dev)) { > > return 0; > > } > > + /* > > + * if the irqfd still in use, means the irqfd was not > > + * release before and don't need to set up > > + */ > > + irqfd = &proxy->vector_irqfd[vector]; > > + if (irqfd->users != 0) { > > + return 0; > > + } > > kvm_virtio_pci_vq_vector_use() has a similar check and it looks to me > kvm_virtio_pci_irqfd_use() can work when users > 0. > > Any reason we need an extra check here? > > Thanks > in function kvm_virtio_pci_vq_vector_use(). this will not init the irqfd, but there will be an irqfd->users++; so the user number will be wrong in this irqfd, There will be check for this in other function sunch like kvm_virtio_pci_vq_vector_release() { VirtIOIRQFD *irqfd = &proxy->vector_irqfd[vector];
if (--irqfd->users == 0) { kvm_irqchip_release_virq(kvm_state, irqfd->virq); } } this will cause problem thanks Cindy > > ret = kvm_virtio_pci_vq_vector_use(proxy, vector); > > if (ret < 0) { > > goto undo; > > } > > + > > /* > > * If guest supports masking, set up irqfd now. > > * Otherwise, delay until unmasked in the frontend. > > @@ -1570,7 +1580,19 @@ static void virtio_pci_common_write(void *opaque, > > hwaddr addr, > > } else { > > val = VIRTIO_NO_VECTOR; > > } > > + vector = vdev->config_vector; > > vdev->config_vector = val; > > + /* > > + *if the val was change from NO_VECTOR, this means the vector maybe > > + * release before, need to check if need to set up > > + */ > > + if ((val != VIRTIO_NO_VECTOR) && (vector == VIRTIO_NO_VECTOR) && > > + (vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) { > > + /* check if use irqfd*/ > > + if (msix_enabled(&proxy->pci_dev) && > > kvm_msi_via_irqfd_enabled()) { > > + kvm_virtio_pci_vector_use_one(proxy, > > VIRTIO_CONFIG_IRQ_IDX); > > + } > > + } > > break; > > case VIRTIO_PCI_COMMON_STATUS: > > if (!(val & VIRTIO_CONFIG_S_DRIVER_OK)) { > > @@ -1611,6 +1633,19 @@ static void virtio_pci_common_write(void *opaque, > > hwaddr addr, > > val = VIRTIO_NO_VECTOR; > > } > > virtio_queue_set_vector(vdev, vdev->queue_sel, val); > > + > > + /* > > + *if the val was change from NO_VECTOR, this means the vector maybe > > + * release before, need to check if need to set up > > + */ > > + > > + if ((val != VIRTIO_NO_VECTOR) && (vector == VIRTIO_NO_VECTOR) && > > + (vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) { > > + /* check if use irqfd*/ > > + if (msix_enabled(&proxy->pci_dev) && > > kvm_msi_via_irqfd_enabled()) { > > + kvm_virtio_pci_vector_use_one(proxy, vdev->queue_sel); > > + } > > + } > > break; > > case VIRTIO_PCI_COMMON_Q_ENABLE: > > if (val == 1) { > > -- > > 2.43.0 > > >