* [PATCH v3] virtio-pci: Fix the crash that the vector was used after released.
@ 2024-04-10 16:12 Cindy Lu
2024-04-10 16:17 ` Michael S. Tsirkin
0 siblings, 1 reply; 3+ messages in thread
From: Cindy Lu @ 2024-04-10 16:12 UTC (permalink / raw
To: lulu, mst, jasowang, qemu-devel
During the booting process of the non-standard image, the behavior of the
called function in qemu is as follows:
1. vhost_net_stop() was triggered by guest image. This will call the function
virtio_pci_set_guest_notifiers() with assgin= false,
virtio_pci_set_guest_notifiers() will release the irqfd for vector 0
2. virtio_reset() was triggered, this will set configure vector to VIRTIO_NO_VECTOR
3.vhost_net_start() was called (at this time, the configure vector is
still VIRTIO_NO_VECTOR) and then call virtio_pci_set_guest_notifiers() with
assgin=true, so the irqfd for vector 0 is still not "init" during this process
4. The system continues to boot and sets the vector back to 0. After that
msix_fire_vector_notifier() was triggered to unmask the vector 0 and meet the crash
To fix the issue, we need to support changing the vector after VIRTIO_CONFIG_S_DRIVER_OK is set.
(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 <lulu@redhat.com>
---
hw/virtio/virtio-pci.c | 30 ++++++++++++++++++++++++++++++
1 file changed, 30 insertions(+)
diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
index 1a7039fb0c..b3b1a4a66f 100644
--- a/hw/virtio/virtio-pci.c
+++ b/hw/virtio/virtio-pci.c
@@ -1570,7 +1570,22 @@ 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 value was changed after DRIVER_OK was set, it means that
+ * we need to release the old vector and set up the new vector.
+ */
+ if ((vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) &&
+ /*check if use the irqfd*/
+ (msix_enabled(&proxy->pci_dev) && kvm_msi_via_irqfd_enabled())) {
+ if (val != VIRTIO_NO_VECTOR) {
+ kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX);
+ }
+ if (vector != VIRTIO_NO_VECTOR) {
+ kvm_virtio_pci_vector_release_one(proxy, VIRTIO_CONFIG_IRQ_IDX);
+ }
+ }
break;
case VIRTIO_PCI_COMMON_STATUS:
if (!(val & VIRTIO_CONFIG_S_DRIVER_OK)) {
@@ -1611,6 +1626,21 @@ 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 value was changed after DRIVER_OK was set, it means that
+ * we need to release the old vector and set up the new vector.
+ */
+ if ((vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) &&
+ /*check if use the irqfd*/
+ (msix_enabled(&proxy->pci_dev) && kvm_msi_via_irqfd_enabled())) {
+ if (val != VIRTIO_NO_VECTOR) {
+ kvm_virtio_pci_vector_use_one(proxy, vdev->queue_sel);
+ }
+ if (vector != VIRTIO_NO_VECTOR) {
+ kvm_virtio_pci_vector_release_one(proxy, vdev->queue_sel);
+ }
+ }
break;
case VIRTIO_PCI_COMMON_Q_ENABLE:
if (val == 1) {
--
2.43.0
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH v3] virtio-pci: Fix the crash that the vector was used after released.
2024-04-10 16:12 [PATCH v3] virtio-pci: Fix the crash that the vector was used after released Cindy Lu
@ 2024-04-10 16:17 ` Michael S. Tsirkin
2024-04-11 1:25 ` Cindy Lu
0 siblings, 1 reply; 3+ messages in thread
From: Michael S. Tsirkin @ 2024-04-10 16:17 UTC (permalink / raw
To: Cindy Lu; +Cc: jasowang, qemu-devel
On Thu, Apr 11, 2024 at 12:12:00AM +0800, Cindy Lu wrote:
> During the booting process of the non-standard image, the behavior of the
> called function in qemu is as follows:
>
> 1. vhost_net_stop() was triggered by guest image. This will call the function
> virtio_pci_set_guest_notifiers() with assgin= false,
> virtio_pci_set_guest_notifiers() will release the irqfd for vector 0
>
> 2. virtio_reset() was triggered, this will set configure vector to VIRTIO_NO_VECTOR
>
> 3.vhost_net_start() was called (at this time, the configure vector is
> still VIRTIO_NO_VECTOR) and then call virtio_pci_set_guest_notifiers() with
> assgin=true, so the irqfd for vector 0 is still not "init" during this process
>
> 4. The system continues to boot and sets the vector back to 0. After that
> msix_fire_vector_notifier() was triggered to unmask the vector 0 and meet the crash
>
> To fix the issue, we need to support changing the vector after VIRTIO_CONFIG_S_DRIVER_OK is set.
>
> (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 <lulu@redhat.com>
> ---
> hw/virtio/virtio-pci.c | 30 ++++++++++++++++++++++++++++++
> 1 file changed, 30 insertions(+)
>
> diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
> index 1a7039fb0c..b3b1a4a66f 100644
> --- a/hw/virtio/virtio-pci.c
> +++ b/hw/virtio/virtio-pci.c
> @@ -1570,7 +1570,22 @@ 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 value was changed after DRIVER_OK was set, it means that
> + * we need to release the old vector and set up the new vector.
> + */
> + if ((vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) &&
> + /*check if use the irqfd*/
> + (msix_enabled(&proxy->pci_dev) && kvm_msi_via_irqfd_enabled())) {
> + if (val != VIRTIO_NO_VECTOR) {
> + kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX);
> + }
> + if (vector != VIRTIO_NO_VECTOR) {
> + kvm_virtio_pci_vector_release_one(proxy, VIRTIO_CONFIG_IRQ_IDX);
> + }
> + }
> break;
> case VIRTIO_PCI_COMMON_STATUS:
> if (!(val & VIRTIO_CONFIG_S_DRIVER_OK)) {
> @@ -1611,6 +1626,21 @@ 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 value was changed after DRIVER_OK was set, it means that
> + * we need to release the old vector and set up the new vector.
> + */
> + if ((vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) &&
> + /*check if use the irqfd*/
by comment style
> + (msix_enabled(&proxy->pci_dev) && kvm_msi_via_irqfd_enabled())) {
> + if (val != VIRTIO_NO_VECTOR) {
> + kvm_virtio_pci_vector_use_one(proxy, vdev->queue_sel);
> + }
> + if (vector != VIRTIO_NO_VECTOR) {
> + kvm_virtio_pci_vector_release_one(proxy, vdev->queue_sel);
> + }
does it matter in which order to do this?
if we release 1st there's more of a chance use will succeeed.
I would also check val != vector
if value did not change there is nothing to do.
> + }
> break;
> case VIRTIO_PCI_COMMON_Q_ENABLE:
> if (val == 1) {
> --
> 2.43.0
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH v3] virtio-pci: Fix the crash that the vector was used after released.
2024-04-10 16:17 ` Michael S. Tsirkin
@ 2024-04-11 1:25 ` Cindy Lu
0 siblings, 0 replies; 3+ messages in thread
From: Cindy Lu @ 2024-04-11 1:25 UTC (permalink / raw
To: Michael S. Tsirkin; +Cc: jasowang, qemu-devel
On Thu, Apr 11, 2024 at 12:18 AM Michael S. Tsirkin <mst@redhat.com> wrote:
>
> On Thu, Apr 11, 2024 at 12:12:00AM +0800, Cindy Lu wrote:
> > During the booting process of the non-standard image, the behavior of the
> > called function in qemu is as follows:
> >
> > 1. vhost_net_stop() was triggered by guest image. This will call the function
> > virtio_pci_set_guest_notifiers() with assgin= false,
> > virtio_pci_set_guest_notifiers() will release the irqfd for vector 0
> >
> > 2. virtio_reset() was triggered, this will set configure vector to VIRTIO_NO_VECTOR
> >
> > 3.vhost_net_start() was called (at this time, the configure vector is
> > still VIRTIO_NO_VECTOR) and then call virtio_pci_set_guest_notifiers() with
> > assgin=true, so the irqfd for vector 0 is still not "init" during this process
> >
> > 4. The system continues to boot and sets the vector back to 0. After that
> > msix_fire_vector_notifier() was triggered to unmask the vector 0 and meet the crash
> >
> > To fix the issue, we need to support changing the vector after VIRTIO_CONFIG_S_DRIVER_OK is set.
> >
> > (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 <lulu@redhat.com>
> > ---
> > hw/virtio/virtio-pci.c | 30 ++++++++++++++++++++++++++++++
> > 1 file changed, 30 insertions(+)
> >
> > diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
> > index 1a7039fb0c..b3b1a4a66f 100644
> > --- a/hw/virtio/virtio-pci.c
> > +++ b/hw/virtio/virtio-pci.c
> > @@ -1570,7 +1570,22 @@ 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 value was changed after DRIVER_OK was set, it means that
> > + * we need to release the old vector and set up the new vector.
> > + */
> > + if ((vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) &&
> > + /*check if use the irqfd*/
> > + (msix_enabled(&proxy->pci_dev) && kvm_msi_via_irqfd_enabled())) {
> > + if (val != VIRTIO_NO_VECTOR) {
> > + kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX);
> > + }
> > + if (vector != VIRTIO_NO_VECTOR) {
> > + kvm_virtio_pci_vector_release_one(proxy, VIRTIO_CONFIG_IRQ_IDX);
> > + }
> > + }
> > break;
> > case VIRTIO_PCI_COMMON_STATUS:
> > if (!(val & VIRTIO_CONFIG_S_DRIVER_OK)) {
> > @@ -1611,6 +1626,21 @@ 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 value was changed after DRIVER_OK was set, it means that
> > + * we need to release the old vector and set up the new vector.
> > + */
> > + if ((vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) &&
> > + /*check if use the irqfd*/
>
> by comment style
will fix this
>
> > + (msix_enabled(&proxy->pci_dev) && kvm_msi_via_irqfd_enabled())) {
> > + if (val != VIRTIO_NO_VECTOR) {
> > + kvm_virtio_pci_vector_use_one(proxy, vdev->queue_sel);
> > + }
> > + if (vector != VIRTIO_NO_VECTOR) {
> > + kvm_virtio_pci_vector_release_one(proxy, vdev->queue_sel);
> > + }
>
> does it matter in which order to do this?
> if we release 1st there's more of a chance use will succeeed.
>
> I would also check val != vector
> if value did not change there is nothing to do.
>
Sure, thanks Michael, will send a new version soon
thanks
cindy
> > + }
> > break;
> > case VIRTIO_PCI_COMMON_Q_ENABLE:
> > if (val == 1) {
> > --
> > 2.43.0
>
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2024-04-11 1:27 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2024-04-10 16:12 [PATCH v3] virtio-pci: Fix the crash that the vector was used after released Cindy Lu
2024-04-10 16:17 ` Michael S. Tsirkin
2024-04-11 1:25 ` Cindy Lu
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