[PATCH v6] virtio-pci: Fix the crash that the vector was used after released.

Cindy Lu posted 1 patch 1 month, 1 week ago
There is a newer version of this series
hw/virtio/virtio-pci.c | 43 ++++++++++++++++++++++++++++++++++++++++--
1 file changed, 41 insertions(+), 2 deletions(-)
[PATCH v6] virtio-pci: Fix the crash that the vector was used after released.
Posted by Cindy Lu 1 month, 1 week ago
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)

Fixes: f9a09ca3ea ("vhost: add support for configure interrupt")
Cc: qemu-stable@nongnu.org

Signed-off-by: Cindy Lu <lulu@redhat.com>
---
 hw/virtio/virtio-pci.c | 43 ++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 41 insertions(+), 2 deletions(-)

diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
index 1a7039fb0c..f83ec92990 100644
--- a/hw/virtio/virtio-pci.c
+++ b/hw/virtio/virtio-pci.c
@@ -1423,6 +1423,36 @@ static int virtio_pci_add_mem_cap(VirtIOPCIProxy *proxy,
 
     return offset;
 }
+static void virtio_pci_set_and_change_vector(VirtIODevice *vdev,
+                                             VirtIOPCIProxy *proxy,
+                                             int queue_no, uint16_t old_vector,
+                                             uint16_t new_vector)
+{
+    /*
+     * If the device uses irqfd and the vector changes after DRIVER_OK is
+     * set, we need to release the old vector and set up the new one.
+     * others just need to set the new vector to device
+     */
+    if ((vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) &&
+        (msix_enabled(&proxy->pci_dev) && kvm_msi_via_irqfd_enabled())) {
+        if (old_vector != VIRTIO_NO_VECTOR) {
+            kvm_virtio_pci_vector_release_one(proxy, queue_no);
+        }
+    }
+    /*set the new vector to device*/
+    if (queue_no == VIRTIO_CONFIG_IRQ_IDX) {
+        vdev->config_vector = new_vector;
+    } else {
+        virtio_queue_set_vector(vdev, queue_no, new_vector);
+    }
+    /* if the new vector chanegd need to set it up */
+    if ((vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) &&
+        (msix_enabled(&proxy->pci_dev) && kvm_msi_via_irqfd_enabled())) {
+        if (new_vector != VIRTIO_NO_VECTOR) {
+            kvm_virtio_pci_vector_use_one(proxy, queue_no);
+        }
+    }
+}
 
 int virtio_pci_add_shm_cap(VirtIOPCIProxy *proxy,
                            uint8_t bar, uint64_t offset, uint64_t length,
@@ -1570,7 +1600,12 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr,
         } else {
             val = VIRTIO_NO_VECTOR;
         }
-        vdev->config_vector = val;
+        vector = vdev->config_vector;
+        /*check if need to change the vector*/
+        if (val != vector) {
+            virtio_pci_set_and_change_vector(vdev, proxy, VIRTIO_CONFIG_IRQ_IDX,
+                                             vector, val);
+        }
         break;
     case VIRTIO_PCI_COMMON_STATUS:
         if (!(val & VIRTIO_CONFIG_S_DRIVER_OK)) {
@@ -1610,7 +1645,11 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr,
         } else {
             val = VIRTIO_NO_VECTOR;
         }
-        virtio_queue_set_vector(vdev, vdev->queue_sel, val);
+        /*check if need to change the vector*/
+        if (val != vector) {
+            virtio_pci_set_and_change_vector(vdev, proxy, vdev->queue_sel,
+                                             vector, val);
+        }
         break;
     case VIRTIO_PCI_COMMON_Q_ENABLE:
         if (val == 1) {
-- 
2.43.0


Re: [PATCH v6] virtio-pci: Fix the crash that the vector was used after released.
Posted by Michael S. Tsirkin 1 month, 1 week ago
On Fri, Apr 12, 2024 at 02:26:55PM +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)
> 
> Fixes: f9a09ca3ea ("vhost: add support for configure interrupt")
> Cc: qemu-stable@nongnu.org
>

empty line not needed here
 
> Signed-off-by: Cindy Lu <lulu@redhat.com>

Reviewed-by: Michael S. Tsirkin <mst@redhat.com>

It's guest triggerable so either we merge this before the release,
or rely on stable process :(

> ---
>  hw/virtio/virtio-pci.c | 43 ++++++++++++++++++++++++++++++++++++++++--
>  1 file changed, 41 insertions(+), 2 deletions(-)
> 
> diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
> index 1a7039fb0c..f83ec92990 100644
> --- a/hw/virtio/virtio-pci.c
> +++ b/hw/virtio/virtio-pci.c
> @@ -1423,6 +1423,36 @@ static int virtio_pci_add_mem_cap(VirtIOPCIProxy *proxy,
>  
>      return offset;
>  }
> +static void virtio_pci_set_and_change_vector(VirtIODevice *vdev,
> +                                             VirtIOPCIProxy *proxy,
> +                                             int queue_no, uint16_t old_vector,
> +                                             uint16_t new_vector)
> +{
> +    /*
> +     * If the device uses irqfd and the vector changes after DRIVER_OK is
> +     * set, we need to release the old vector and set up the new one.
> +     * others just need to set the new vector to device
> +     */
> +    if ((vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) &&
> +        (msix_enabled(&proxy->pci_dev) && kvm_msi_via_irqfd_enabled())) {
> +        if (old_vector != VIRTIO_NO_VECTOR) {
> +            kvm_virtio_pci_vector_release_one(proxy, queue_no);
> +        }
> +    }
> +    /*set the new vector to device*/
> +    if (queue_no == VIRTIO_CONFIG_IRQ_IDX) {
> +        vdev->config_vector = new_vector;
> +    } else {
> +        virtio_queue_set_vector(vdev, queue_no, new_vector);
> +    }
> +    /* if the new vector chanegd need to set it up */

typo

> +    if ((vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) &&
> +        (msix_enabled(&proxy->pci_dev) && kvm_msi_via_irqfd_enabled())) {
> +        if (new_vector != VIRTIO_NO_VECTOR) {
> +            kvm_virtio_pci_vector_use_one(proxy, queue_no);
> +        }
> +    }
> +}
>  
>  int virtio_pci_add_shm_cap(VirtIOPCIProxy *proxy,
>                             uint8_t bar, uint64_t offset, uint64_t length,
> @@ -1570,7 +1600,12 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr,
>          } else {
>              val = VIRTIO_NO_VECTOR;
>          }
> -        vdev->config_vector = val;
> +        vector = vdev->config_vector;
> +        /*check if need to change the vector*/
> +        if (val != vector) {
> +            virtio_pci_set_and_change_vector(vdev, proxy, VIRTIO_CONFIG_IRQ_IDX,
> +                                             vector, val);
> +        }
>          break;
>      case VIRTIO_PCI_COMMON_STATUS:
>          if (!(val & VIRTIO_CONFIG_S_DRIVER_OK)) {
> @@ -1610,7 +1645,11 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr,
>          } else {
>              val = VIRTIO_NO_VECTOR;
>          }
> -        virtio_queue_set_vector(vdev, vdev->queue_sel, val);
> +        /*check if need to change the vector*/
> +        if (val != vector) {
> +            virtio_pci_set_and_change_vector(vdev, proxy, vdev->queue_sel,
> +                                             vector, val);
> +        }
>          break;
>      case VIRTIO_PCI_COMMON_Q_ENABLE:
>          if (val == 1) {
> -- 
> 2.43.0


Re: [PATCH v6] virtio-pci: Fix the crash that the vector was used after released.
Posted by Cindy Lu 1 month, 1 week ago
On Mon, Apr 15, 2024 at 4:32 PM Michael S. Tsirkin <mst@redhat.com> wrote:
>
> On Fri, Apr 12, 2024 at 02:26:55PM +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)
> >
> > Fixes: f9a09ca3ea ("vhost: add support for configure interrupt")
> > Cc: qemu-stable@nongnu.org
> >
>
> empty line not needed here
>
will fix this

> > Signed-off-by: Cindy Lu <lulu@redhat.com>
>
> Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
>
> It's guest triggerable so either we merge this before the release,
> or rely on stable process :(
>
thanks a lot for explain this, but I'm still not  very clear about this
do you mean this can not be merged before 2024-04-23?
https://wiki.qemu.org/Planning/9.0#Release_Schedule
Really Thanks for your help
thanks
cindy

> > ---
> >  hw/virtio/virtio-pci.c | 43 ++++++++++++++++++++++++++++++++++++++++--
> >  1 file changed, 41 insertions(+), 2 deletions(-)
> >
> > diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
> > index 1a7039fb0c..f83ec92990 100644
> > --- a/hw/virtio/virtio-pci.c
> > +++ b/hw/virtio/virtio-pci.c
> > @@ -1423,6 +1423,36 @@ static int virtio_pci_add_mem_cap(VirtIOPCIProxy *proxy,
> >
> >      return offset;
> >  }
> > +static void virtio_pci_set_and_change_vector(VirtIODevice *vdev,
> > +                                             VirtIOPCIProxy *proxy,
> > +                                             int queue_no, uint16_t old_vector,
> > +                                             uint16_t new_vector)
> > +{
> > +    /*
> > +     * If the device uses irqfd and the vector changes after DRIVER_OK is
> > +     * set, we need to release the old vector and set up the new one.
> > +     * others just need to set the new vector to device
> > +     */
> > +    if ((vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) &&
> > +        (msix_enabled(&proxy->pci_dev) && kvm_msi_via_irqfd_enabled())) {
> > +        if (old_vector != VIRTIO_NO_VECTOR) {
> > +            kvm_virtio_pci_vector_release_one(proxy, queue_no);
> > +        }
> > +    }
> > +    /*set the new vector to device*/
> > +    if (queue_no == VIRTIO_CONFIG_IRQ_IDX) {
> > +        vdev->config_vector = new_vector;
> > +    } else {
> > +        virtio_queue_set_vector(vdev, queue_no, new_vector);
> > +    }
> > +    /* if the new vector chanegd need to set it up */
>
> typo
>
sure will fix this
thanks

cindy
> > +    if ((vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) &&
> > +        (msix_enabled(&proxy->pci_dev) && kvm_msi_via_irqfd_enabled())) {
> > +        if (new_vector != VIRTIO_NO_VECTOR) {
> > +            kvm_virtio_pci_vector_use_one(proxy, queue_no);
> > +        }
> > +    }
> > +}
> >
> >  int virtio_pci_add_shm_cap(VirtIOPCIProxy *proxy,
> >                             uint8_t bar, uint64_t offset, uint64_t length,
> > @@ -1570,7 +1600,12 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr,
> >          } else {
> >              val = VIRTIO_NO_VECTOR;
> >          }
> > -        vdev->config_vector = val;
> > +        vector = vdev->config_vector;
> > +        /*check if need to change the vector*/
> > +        if (val != vector) {
> > +            virtio_pci_set_and_change_vector(vdev, proxy, VIRTIO_CONFIG_IRQ_IDX,
> > +                                             vector, val);
> > +        }
> >          break;
> >      case VIRTIO_PCI_COMMON_STATUS:
> >          if (!(val & VIRTIO_CONFIG_S_DRIVER_OK)) {
> > @@ -1610,7 +1645,11 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr,
> >          } else {
> >              val = VIRTIO_NO_VECTOR;
> >          }
> > -        virtio_queue_set_vector(vdev, vdev->queue_sel, val);
> > +        /*check if need to change the vector*/
> > +        if (val != vector) {
> > +            virtio_pci_set_and_change_vector(vdev, proxy, vdev->queue_sel,
> > +                                             vector, val);
> > +        }
> >          break;
> >      case VIRTIO_PCI_COMMON_Q_ENABLE:
> >          if (val == 1) {
> > --
> > 2.43.0
>
Re: [PATCH v6] virtio-pci: Fix the crash that the vector was used after released.
Posted by Michael S. Tsirkin 1 month, 1 week ago
On Mon, Apr 15, 2024 at 05:11:05PM +0800, Cindy Lu wrote:
> On Mon, Apr 15, 2024 at 4:32 PM Michael S. Tsirkin <mst@redhat.com> wrote:
> >
> > On Fri, Apr 12, 2024 at 02:26:55PM +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)
> > >
> > > Fixes: f9a09ca3ea ("vhost: add support for configure interrupt")
> > > Cc: qemu-stable@nongnu.org
> > >
> >
> > empty line not needed here
> >
> will fix this
> 
> > > Signed-off-by: Cindy Lu <lulu@redhat.com>
> >
> > Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
> >
> > It's guest triggerable so either we merge this before the release,
> > or rely on stable process :(
> >
> thanks a lot for explain this, but I'm still not  very clear about this
> do you mean this can not be merged before 2024-04-23?
> https://wiki.qemu.org/Planning/9.0#Release_Schedule
> Really Thanks for your help
> thanks
> cindy
> 
> > > ---
> > >  hw/virtio/virtio-pci.c | 43 ++++++++++++++++++++++++++++++++++++++++--
> > >  1 file changed, 41 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
> > > index 1a7039fb0c..f83ec92990 100644
> > > --- a/hw/virtio/virtio-pci.c
> > > +++ b/hw/virtio/virtio-pci.c
> > > @@ -1423,6 +1423,36 @@ static int virtio_pci_add_mem_cap(VirtIOPCIProxy *proxy,
> > >
> > >      return offset;
> > >  }
> > > +static void virtio_pci_set_and_change_vector(VirtIODevice *vdev,
> > > +                                             VirtIOPCIProxy *proxy,
> > > +                                             int queue_no, uint16_t old_vector,
> > > +                                             uint16_t new_vector)
> > > +{
> > > +    /*
> > > +     * If the device uses irqfd and the vector changes after DRIVER_OK is
> > > +     * set, we need to release the old vector and set up the new one.
> > > +     * others just need to set the new vector to device
> > > +     */
> > > +    if ((vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) &&
> > > +        (msix_enabled(&proxy->pci_dev) && kvm_msi_via_irqfd_enabled())) {
> > > +        if (old_vector != VIRTIO_NO_VECTOR) {
> > > +            kvm_virtio_pci_vector_release_one(proxy, queue_no);
> > > +        }
> > > +    }
> > > +    /*set the new vector to device*/
> > > +    if (queue_no == VIRTIO_CONFIG_IRQ_IDX) {
> > > +        vdev->config_vector = new_vector;
> > > +    } else {
> > > +        virtio_queue_set_vector(vdev, queue_no, new_vector);
> > > +    }
> > > +    /* if the new vector chanegd need to set it up */
> >
> > typo
> >
> sure will fix this
> thanks
> 
> cindy


actually more issues.
I posted v7 pls with most things fixed - pls start with that.


> > > +    if ((vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) &&
> > > +        (msix_enabled(&proxy->pci_dev) && kvm_msi_via_irqfd_enabled())) {
> > > +        if (new_vector != VIRTIO_NO_VECTOR) {
> > > +            kvm_virtio_pci_vector_use_one(proxy, queue_no);
> > > +        }
> > > +    }
> > > +}
> > >
> > >  int virtio_pci_add_shm_cap(VirtIOPCIProxy *proxy,
> > >                             uint8_t bar, uint64_t offset, uint64_t length,
> > > @@ -1570,7 +1600,12 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr,
> > >          } else {
> > >              val = VIRTIO_NO_VECTOR;
> > >          }
> > > -        vdev->config_vector = val;
> > > +        vector = vdev->config_vector;
> > > +        /*check if need to change the vector*/
> > > +        if (val != vector) {
> > > +            virtio_pci_set_and_change_vector(vdev, proxy, VIRTIO_CONFIG_IRQ_IDX,
> > > +                                             vector, val);
> > > +        }
> > >          break;
> > >      case VIRTIO_PCI_COMMON_STATUS:
> > >          if (!(val & VIRTIO_CONFIG_S_DRIVER_OK)) {
> > > @@ -1610,7 +1645,11 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr,
> > >          } else {
> > >              val = VIRTIO_NO_VECTOR;
> > >          }
> > > -        virtio_queue_set_vector(vdev, vdev->queue_sel, val);
> > > +        /*check if need to change the vector*/
> > > +        if (val != vector) {
> > > +            virtio_pci_set_and_change_vector(vdev, proxy, vdev->queue_sel,
> > > +                                             vector, val);
> > > +        }
> > >          break;
> > >      case VIRTIO_PCI_COMMON_Q_ENABLE:
> > >          if (val == 1) {
> > > --
> > > 2.43.0
> >


Re: [PATCH v6] virtio-pci: Fix the crash that the vector was used after released.
Posted by Jason Wang 1 month, 1 week ago
On Fri, Apr 12, 2024 at 2:28 PM Cindy Lu <lulu@redhat.com> 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)
>
> Fixes: f9a09ca3ea ("vhost: add support for configure interrupt")
> Cc: qemu-stable@nongnu.org
>
> Signed-off-by: Cindy Lu <lulu@redhat.com>

Acked-by: Jason Wang <jasowang@redhat.com>

Thanks
Re: [PATCH v6] virtio-pci: Fix the crash that the vector was used after released.
Posted by Cindy Lu 1 month, 1 week ago
Hi All
I apologize for bothering you again
I send the new patch is because I found that the function
kvm_virtio_pci_vector_use_one/kvm_virtio_pci_vector_release_one
can only change the vector that already set to the device.
....
  ret = virtio_pci_get_notifier(proxy, queue_no, &n, &vector);
  if (ret < 0) {
    return;
  }
...
So I move the setting vector into the function
virtio_pci_set_and_change_vector()
the other part are the same .

the sanity test is passed and the qemu qtest is also passed

Thanks
Cindy

On Fri, Apr 12, 2024 at 2:28 PM Cindy Lu <lulu@redhat.com> 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)
>
> Fixes: f9a09ca3ea ("vhost: add support for configure interrupt")
> Cc: qemu-stable@nongnu.org
>
> Signed-off-by: Cindy Lu <lulu@redhat.com>
> ---
>  hw/virtio/virtio-pci.c | 43 ++++++++++++++++++++++++++++++++++++++++--
>  1 file changed, 41 insertions(+), 2 deletions(-)
>
> diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
> index 1a7039fb0c..f83ec92990 100644
> --- a/hw/virtio/virtio-pci.c
> +++ b/hw/virtio/virtio-pci.c
> @@ -1423,6 +1423,36 @@ static int virtio_pci_add_mem_cap(VirtIOPCIProxy *proxy,
>
>      return offset;
>  }
> +static void virtio_pci_set_and_change_vector(VirtIODevice *vdev,
> +                                             VirtIOPCIProxy *proxy,
> +                                             int queue_no, uint16_t old_vector,
> +                                             uint16_t new_vector)
> +{
> +    /*
> +     * If the device uses irqfd and the vector changes after DRIVER_OK is
> +     * set, we need to release the old vector and set up the new one.
> +     * others just need to set the new vector to device
> +     */
> +    if ((vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) &&
> +        (msix_enabled(&proxy->pci_dev) && kvm_msi_via_irqfd_enabled())) {
> +        if (old_vector != VIRTIO_NO_VECTOR) {
> +            kvm_virtio_pci_vector_release_one(proxy, queue_no);
> +        }
> +    }
> +    /*set the new vector to device*/
> +    if (queue_no == VIRTIO_CONFIG_IRQ_IDX) {
> +        vdev->config_vector = new_vector;
> +    } else {
> +        virtio_queue_set_vector(vdev, queue_no, new_vector);
> +    }
> +    /* if the new vector chanegd need to set it up */
> +    if ((vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) &&
> +        (msix_enabled(&proxy->pci_dev) && kvm_msi_via_irqfd_enabled())) {
> +        if (new_vector != VIRTIO_NO_VECTOR) {
> +            kvm_virtio_pci_vector_use_one(proxy, queue_no);
> +        }
> +    }
> +}
>
>  int virtio_pci_add_shm_cap(VirtIOPCIProxy *proxy,
>                             uint8_t bar, uint64_t offset, uint64_t length,
> @@ -1570,7 +1600,12 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr,
>          } else {
>              val = VIRTIO_NO_VECTOR;
>          }
> -        vdev->config_vector = val;
> +        vector = vdev->config_vector;
> +        /*check if need to change the vector*/
> +        if (val != vector) {
> +            virtio_pci_set_and_change_vector(vdev, proxy, VIRTIO_CONFIG_IRQ_IDX,
> +                                             vector, val);
> +        }
>          break;
>      case VIRTIO_PCI_COMMON_STATUS:
>          if (!(val & VIRTIO_CONFIG_S_DRIVER_OK)) {
> @@ -1610,7 +1645,11 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr,
>          } else {
>              val = VIRTIO_NO_VECTOR;
>          }
> -        virtio_queue_set_vector(vdev, vdev->queue_sel, val);
> +        /*check if need to change the vector*/
> +        if (val != vector) {
> +            virtio_pci_set_and_change_vector(vdev, proxy, vdev->queue_sel,
> +                                             vector, val);
> +        }
>          break;
>      case VIRTIO_PCI_COMMON_Q_ENABLE:
>          if (val == 1) {
> --
> 2.43.0
>
Re: [PATCH v6] virtio-pci: Fix the crash that the vector was used after released.
Posted by Lei Yang 1 month, 1 week ago
QE tested this patch with regression tests, everything works fine.

Tested-by: Lei Yang <leiyang@redhat.com>

On Fri, Apr 12, 2024 at 2:37 PM Cindy Lu <lulu@redhat.com> wrote:
>
> Hi All
> I apologize for bothering you again
> I send the new patch is because I found that the function
> kvm_virtio_pci_vector_use_one/kvm_virtio_pci_vector_release_one
> can only change the vector that already set to the device.
> ....
>   ret = virtio_pci_get_notifier(proxy, queue_no, &n, &vector);
>   if (ret < 0) {
>     return;
>   }
> ...
> So I move the setting vector into the function
> virtio_pci_set_and_change_vector()
> the other part are the same .
>
> the sanity test is passed and the qemu qtest is also passed
>
> Thanks
> Cindy
>
> On Fri, Apr 12, 2024 at 2:28 PM Cindy Lu <lulu@redhat.com> 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)
> >
> > Fixes: f9a09ca3ea ("vhost: add support for configure interrupt")
> > Cc: qemu-stable@nongnu.org
> >
> > Signed-off-by: Cindy Lu <lulu@redhat.com>
> > ---
> >  hw/virtio/virtio-pci.c | 43 ++++++++++++++++++++++++++++++++++++++++--
> >  1 file changed, 41 insertions(+), 2 deletions(-)
> >
> > diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
> > index 1a7039fb0c..f83ec92990 100644
> > --- a/hw/virtio/virtio-pci.c
> > +++ b/hw/virtio/virtio-pci.c
> > @@ -1423,6 +1423,36 @@ static int virtio_pci_add_mem_cap(VirtIOPCIProxy *proxy,
> >
> >      return offset;
> >  }
> > +static void virtio_pci_set_and_change_vector(VirtIODevice *vdev,
> > +                                             VirtIOPCIProxy *proxy,
> > +                                             int queue_no, uint16_t old_vector,
> > +                                             uint16_t new_vector)
> > +{
> > +    /*
> > +     * If the device uses irqfd and the vector changes after DRIVER_OK is
> > +     * set, we need to release the old vector and set up the new one.
> > +     * others just need to set the new vector to device
> > +     */
> > +    if ((vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) &&
> > +        (msix_enabled(&proxy->pci_dev) && kvm_msi_via_irqfd_enabled())) {
> > +        if (old_vector != VIRTIO_NO_VECTOR) {
> > +            kvm_virtio_pci_vector_release_one(proxy, queue_no);
> > +        }
> > +    }
> > +    /*set the new vector to device*/
> > +    if (queue_no == VIRTIO_CONFIG_IRQ_IDX) {
> > +        vdev->config_vector = new_vector;
> > +    } else {
> > +        virtio_queue_set_vector(vdev, queue_no, new_vector);
> > +    }
> > +    /* if the new vector chanegd need to set it up */
> > +    if ((vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) &&
> > +        (msix_enabled(&proxy->pci_dev) && kvm_msi_via_irqfd_enabled())) {
> > +        if (new_vector != VIRTIO_NO_VECTOR) {
> > +            kvm_virtio_pci_vector_use_one(proxy, queue_no);
> > +        }
> > +    }
> > +}
> >
> >  int virtio_pci_add_shm_cap(VirtIOPCIProxy *proxy,
> >                             uint8_t bar, uint64_t offset, uint64_t length,
> > @@ -1570,7 +1600,12 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr,
> >          } else {
> >              val = VIRTIO_NO_VECTOR;
> >          }
> > -        vdev->config_vector = val;
> > +        vector = vdev->config_vector;
> > +        /*check if need to change the vector*/
> > +        if (val != vector) {
> > +            virtio_pci_set_and_change_vector(vdev, proxy, VIRTIO_CONFIG_IRQ_IDX,
> > +                                             vector, val);
> > +        }
> >          break;
> >      case VIRTIO_PCI_COMMON_STATUS:
> >          if (!(val & VIRTIO_CONFIG_S_DRIVER_OK)) {
> > @@ -1610,7 +1645,11 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr,
> >          } else {
> >              val = VIRTIO_NO_VECTOR;
> >          }
> > -        virtio_queue_set_vector(vdev, vdev->queue_sel, val);
> > +        /*check if need to change the vector*/
> > +        if (val != vector) {
> > +            virtio_pci_set_and_change_vector(vdev, proxy, vdev->queue_sel,
> > +                                             vector, val);
> > +        }
> >          break;
> >      case VIRTIO_PCI_COMMON_Q_ENABLE:
> >          if (val == 1) {
> > --
> > 2.43.0
> >
>
>