* Re: [PATCH] hw/virtio: Update vring after modifying its queue size
2021-08-25 22:42 [PATCH] hw/virtio: Update vring after modifying its queue size Philippe Mathieu-Daudé
@ 2021-08-25 22:47 ` Philippe Mathieu-Daudé
2021-08-26 3:28 ` Jason Wang
` (2 subsequent siblings)
3 siblings, 0 replies; 9+ messages in thread
From: Philippe Mathieu-Daudé @ 2021-08-25 22:47 UTC (permalink / raw)
To: qemu-devel
Cc: Michael S. Tsirkin, Jason Wang, Cornelia Huck, Li Qiang,
Qiuhao Li, Alexander Bulekov, Stefan Hajnoczi, Paolo Bonzini
On 8/26/21 12:42 AM, Philippe Mathieu-Daudé wrote:
> When a ring queue size is modified, we need to call
> virtio_queue_update_rings() to re-init the memory region
> caches. Otherwise the region might have outdated memory
> size, and later load/store access might trigger an
> assertion, such:
>
> qemu-system-i386: include/exec/memory_ldst_cached.h.inc:30: uint16_t address_space_lduw_le_cached(MemoryRegionCache *, hwaddr, MemTxAttrs, MemTxResult *):
> Assertion `addr < cache->len && 2 <= cache->len - addr' failed.
> Thread 1 "qemu-system-i38" received signal SIGABRT, Aborted.
> 0x00007ffff4d312a2 in raise () from /lib64/libc.so.6
> (gdb) bt
> #1 0x00007ffff4d1a8a4 in abort () at /lib64/libc.so.6
> #4 0x0000555558f2b8ec in address_space_lduw_le_cached (cache=0x61300010a7c0, addr=134, attrs=..., result=0x0) at include/exec/memory_ldst_cached.h.inc:30
> #5 0x0000555558f2ac6b in lduw_le_phys_cached (cache=0x61300010a7c0, addr=134) at include/exec/memory_ldst_phys.h.inc:67
> #6 0x0000555558f2a3cd in virtio_lduw_phys_cached (vdev=0x62d00003a680, cache=0x61300010a7c0, pa=134) at include/hw/virtio/virtio-access.h:166
> #7 0x0000555558f300ea in vring_avail_ring (vq=0x7fffdd55d8a0, i=65) at hw/virtio/virtio.c:326
> #8 0x0000555558f33b10 in vring_get_used_event (vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:332
> #9 0x0000555558f33677 in virtio_split_should_notify (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:2471
> #10 0x0000555558f1859f in virtio_should_notify (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:2523
> #11 0x0000555558f188cc in virtio_notify (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:2565
> #12 0x0000555557c2bd52 in virtio_input_handle_sts (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/input/virtio-input.c:100
> #13 0x0000555558f16df7 in virtio_queue_notify (vdev=0x62d00003a680, n=1) at hw/virtio/virtio.c:2363
> #14 0x00005555583f45c0 in virtio_pci_notify_write (opaque=0x62d000032400, addr=7, val=0, size=1) at hw/virtio/virtio-pci.c:1369
> #15 0x0000555558b80b04 in memory_region_write_accessor (mr=0x62d000033190, addr=7, value=0x7fffffff8eb0, size=1, shift=0, mask=255, attrs=...) at softmmu/memory.c:492
Earlier call which updated vring.num:
memory_region_ops_write cpu -1 mr 0x62d000032e60 addr 0xe0004018 value
0x41 size 1 name 'virtio-pci-common-virtio-input'
Thread 1 "qemu-system-i38" hit Breakpoint 1, virtio_queue_set_num
(vdev=0x62d00003a680, n=1, num=65) at hw/virtio/virtio.c:2276
2276 if (!!num != !!vdev->vq[n].vring.num ||
(gdb) bt
#0 virtio_queue_set_num (vdev=0x62d00003a680, n=1, num=65) at
hw/virtio/virtio.c:2276
#1 0x00005555583f2a2c in virtio_pci_common_write
(opaque=0x62d000032400, addr=24, val=65, size=1) at
hw/virtio/virtio-pci.c:1297
#2 0x0000555558b81b04 in memory_region_write_accessor
(mr=0x62d000032e60, addr=24, value=0x7fffffff8eb0, size=1, shift=0,
mask=255, attrs=...) at softmmu/memory.c:492
#3 0x0000555558b81442 in access_with_adjusted_size (addr=24,
value=0x7fffffff8eb0, size=1, access_size_min=1, access_size_max=4,
access_fn=
0x555558b81500 <memory_region_write_accessor>, mr=0x62d000032e60,
attrs=...) at softmmu/memory.c:554
#4 0x0000555558b7fd57 in memory_region_dispatch_write
(mr=0x62d000032e60, addr=24, data=65, op=MO_8, attrs=...) at
softmmu/memory.c:1504
#5 0x0000555558b513f4 in flatview_write_continue (fv=0x60600005cc00,
addr=3758112792, attrs=..., ptr=0x6020000dbb90, len=1, addr1=24, l=1,
mr=0x62d000032e60)
at softmmu/physmem.c:2777
#6 0x0000555558b3fdd0 in flatview_write (fv=0x60600005cc00,
addr=3758112792, attrs=..., buf=0x6020000dbb90, len=1) at
softmmu/physmem.c:2817
#7 0x0000555558b3f959 in address_space_write (as=0x60800000d920,
addr=3758112792, attrs=..., buf=0x6020000dbb90, len=1) at
softmmu/physmem.c:2909
> Reported-by: Qiuhao Li <Qiuhao.Li@outlook.com>
> Fixes: ab223c9518e ("virtio: allow virtio-1 queue layout")
> Resolves: https://gitlab.com/qemu-project/qemu/-/issues/302
BTW this also fixes #300 and #301 :)
> BugLink: https://bugs.launchpad.net/qemu/+bug/1913510
> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> ---
> hw/virtio/virtio.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
> index 874377f37a7..04ffe5f420e 100644
> --- a/hw/virtio/virtio.c
> +++ b/hw/virtio/virtio.c
> @@ -2255,6 +2255,7 @@ void virtio_queue_set_num(VirtIODevice *vdev, int n, int num)
> return;
> }
> vdev->vq[n].vring.num = num;
> + virtio_queue_update_rings(vdev, n);
> }
>
> VirtQueue *virtio_vector_first_queue(VirtIODevice *vdev, uint16_t vector)
>
^ permalink raw reply [flat|nested] 9+ messages in thread* Re: [PATCH] hw/virtio: Update vring after modifying its queue size
2021-08-25 22:42 [PATCH] hw/virtio: Update vring after modifying its queue size Philippe Mathieu-Daudé
2021-08-25 22:47 ` Philippe Mathieu-Daudé
@ 2021-08-26 3:28 ` Jason Wang
2021-08-26 8:40 ` Philippe Mathieu-Daudé
2021-09-02 14:56 ` Stefan Hajnoczi
2021-09-14 11:12 ` Alexander Bulekov
3 siblings, 1 reply; 9+ messages in thread
From: Jason Wang @ 2021-08-26 3:28 UTC (permalink / raw)
To: Philippe Mathieu-Daudé
Cc: Michael S. Tsirkin, Cornelia Huck, Li Qiang, qemu-devel,
Qiuhao Li, Alexander Bulekov, Stefan Hajnoczi, Paolo Bonzini
On Thu, Aug 26, 2021 at 6:43 AM Philippe Mathieu-Daudé
<philmd@redhat.com> wrote:
>
> When a ring queue size is modified, we need to call
> virtio_queue_update_rings() to re-init the memory region
> caches. Otherwise the region might have outdated memory
> size, and later load/store access might trigger an
> assertion, such:
>
> qemu-system-i386: include/exec/memory_ldst_cached.h.inc:30: uint16_t address_space_lduw_le_cached(MemoryRegionCache *, hwaddr, MemTxAttrs, MemTxResult *):
> Assertion `addr < cache->len && 2 <= cache->len - addr' failed.
> Thread 1 "qemu-system-i38" received signal SIGABRT, Aborted.
> 0x00007ffff4d312a2 in raise () from /lib64/libc.so.6
> (gdb) bt
> #1 0x00007ffff4d1a8a4 in abort () at /lib64/libc.so.6
> #4 0x0000555558f2b8ec in address_space_lduw_le_cached (cache=0x61300010a7c0, addr=134, attrs=..., result=0x0) at include/exec/memory_ldst_cached.h.inc:30
> #5 0x0000555558f2ac6b in lduw_le_phys_cached (cache=0x61300010a7c0, addr=134) at include/exec/memory_ldst_phys.h.inc:67
> #6 0x0000555558f2a3cd in virtio_lduw_phys_cached (vdev=0x62d00003a680, cache=0x61300010a7c0, pa=134) at include/hw/virtio/virtio-access.h:166
> #7 0x0000555558f300ea in vring_avail_ring (vq=0x7fffdd55d8a0, i=65) at hw/virtio/virtio.c:326
> #8 0x0000555558f33b10 in vring_get_used_event (vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:332
> #9 0x0000555558f33677 in virtio_split_should_notify (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:2471
> #10 0x0000555558f1859f in virtio_should_notify (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:2523
> #11 0x0000555558f188cc in virtio_notify (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:2565
> #12 0x0000555557c2bd52 in virtio_input_handle_sts (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/input/virtio-input.c:100
> #13 0x0000555558f16df7 in virtio_queue_notify (vdev=0x62d00003a680, n=1) at hw/virtio/virtio.c:2363
> #14 0x00005555583f45c0 in virtio_pci_notify_write (opaque=0x62d000032400, addr=7, val=0, size=1) at hw/virtio/virtio-pci.c:1369
> #15 0x0000555558b80b04 in memory_region_write_accessor (mr=0x62d000033190, addr=7, value=0x7fffffff8eb0, size=1, shift=0, mask=255, attrs=...) at softmmu/memory.c:492
>
> Reported-by: Qiuhao Li <Qiuhao.Li@outlook.com>
> Fixes: ab223c9518e ("virtio: allow virtio-1 queue layout")
> Resolves: https://gitlab.com/qemu-project/qemu/-/issues/302
> BugLink: https://bugs.launchpad.net/qemu/+bug/1913510
> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> ---
> hw/virtio/virtio.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
> index 874377f37a7..04ffe5f420e 100644
> --- a/hw/virtio/virtio.c
> +++ b/hw/virtio/virtio.c
> @@ -2255,6 +2255,7 @@ void virtio_queue_set_num(VirtIODevice *vdev, int n, int num)
> return;
> }
> vdev->vq[n].vring.num = num;
> + virtio_queue_update_rings(vdev, n);
> }
>
Spec said:
"
The driver MUST configure the other virtqueue fields before enabling
the virtqueue with queue_enable.
"
So I think we should forbid the num to be changed if the virtqueue is ready?
Thanks
> VirtQueue *virtio_vector_first_queue(VirtIODevice *vdev, uint16_t vector)
> --
> 2.31.1
>
^ permalink raw reply [flat|nested] 9+ messages in thread* Re: [PATCH] hw/virtio: Update vring after modifying its queue size
2021-08-26 3:28 ` Jason Wang
@ 2021-08-26 8:40 ` Philippe Mathieu-Daudé
2021-08-26 15:16 ` Philippe Mathieu-Daudé
2021-08-30 21:16 ` Michael S. Tsirkin
0 siblings, 2 replies; 9+ messages in thread
From: Philippe Mathieu-Daudé @ 2021-08-26 8:40 UTC (permalink / raw)
To: Jason Wang
Cc: Michael S. Tsirkin, Cornelia Huck, Li Qiang, qemu-devel,
Qiuhao Li, Alexander Bulekov, Stefan Hajnoczi, Paolo Bonzini
On 8/26/21 5:28 AM, Jason Wang wrote:
> On Thu, Aug 26, 2021 at 6:43 AM Philippe Mathieu-Daudé
> <philmd@redhat.com> wrote:
>>
>> When a ring queue size is modified, we need to call
>> virtio_queue_update_rings() to re-init the memory region
>> caches. Otherwise the region might have outdated memory
>> size, and later load/store access might trigger an
>> assertion, such:
>>
>> qemu-system-i386: include/exec/memory_ldst_cached.h.inc:30: uint16_t address_space_lduw_le_cached(MemoryRegionCache *, hwaddr, MemTxAttrs, MemTxResult *):
>> Assertion `addr < cache->len && 2 <= cache->len - addr' failed.
>> Thread 1 "qemu-system-i38" received signal SIGABRT, Aborted.
>> 0x00007ffff4d312a2 in raise () from /lib64/libc.so.6
>> (gdb) bt
>> #1 0x00007ffff4d1a8a4 in abort () at /lib64/libc.so.6
>> #4 0x0000555558f2b8ec in address_space_lduw_le_cached (cache=0x61300010a7c0, addr=134, attrs=..., result=0x0) at include/exec/memory_ldst_cached.h.inc:30
>> #5 0x0000555558f2ac6b in lduw_le_phys_cached (cache=0x61300010a7c0, addr=134) at include/exec/memory_ldst_phys.h.inc:67
>> #6 0x0000555558f2a3cd in virtio_lduw_phys_cached (vdev=0x62d00003a680, cache=0x61300010a7c0, pa=134) at include/hw/virtio/virtio-access.h:166
>> #7 0x0000555558f300ea in vring_avail_ring (vq=0x7fffdd55d8a0, i=65) at hw/virtio/virtio.c:326
>> #8 0x0000555558f33b10 in vring_get_used_event (vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:332
>> #9 0x0000555558f33677 in virtio_split_should_notify (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:2471
>> #10 0x0000555558f1859f in virtio_should_notify (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:2523
>> #11 0x0000555558f188cc in virtio_notify (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:2565
>> #12 0x0000555557c2bd52 in virtio_input_handle_sts (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/input/virtio-input.c:100
>> #13 0x0000555558f16df7 in virtio_queue_notify (vdev=0x62d00003a680, n=1) at hw/virtio/virtio.c:2363
>> #14 0x00005555583f45c0 in virtio_pci_notify_write (opaque=0x62d000032400, addr=7, val=0, size=1) at hw/virtio/virtio-pci.c:1369
>> #15 0x0000555558b80b04 in memory_region_write_accessor (mr=0x62d000033190, addr=7, value=0x7fffffff8eb0, size=1, shift=0, mask=255, attrs=...) at softmmu/memory.c:492
>>
>> Reported-by: Qiuhao Li <Qiuhao.Li@outlook.com>
>> Fixes: ab223c9518e ("virtio: allow virtio-1 queue layout")
>> Resolves: https://gitlab.com/qemu-project/qemu/-/issues/302
>> BugLink: https://bugs.launchpad.net/qemu/+bug/1913510
>> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
>> ---
>> hw/virtio/virtio.c | 1 +
>> 1 file changed, 1 insertion(+)
>>
>> diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
>> index 874377f37a7..04ffe5f420e 100644
>> --- a/hw/virtio/virtio.c
>> +++ b/hw/virtio/virtio.c
>> @@ -2255,6 +2255,7 @@ void virtio_queue_set_num(VirtIODevice *vdev, int n, int num)
>> return;
>> }
>> vdev->vq[n].vring.num = num;
>> + virtio_queue_update_rings(vdev, n);
>> }
>>
>
> Spec said:
>
> "
> The driver MUST configure the other virtqueue fields before enabling
> the virtqueue with queue_enable.
> "
>
> So I think we should forbid the num to be changed if the virtqueue is ready?
Alright. virtio_pci_common_write() doesn't report errors although.
^ permalink raw reply [flat|nested] 9+ messages in thread* Re: [PATCH] hw/virtio: Update vring after modifying its queue size
2021-08-26 8:40 ` Philippe Mathieu-Daudé
@ 2021-08-26 15:16 ` Philippe Mathieu-Daudé
2021-08-30 21:15 ` Michael S. Tsirkin
2021-08-30 21:16 ` Michael S. Tsirkin
1 sibling, 1 reply; 9+ messages in thread
From: Philippe Mathieu-Daudé @ 2021-08-26 15:16 UTC (permalink / raw)
To: Jason Wang
Cc: Michael S. Tsirkin, Cornelia Huck, Li Qiang, qemu-devel,
Qiuhao Li, Alexander Bulekov, Stefan Hajnoczi, Paolo Bonzini
On 8/26/21 10:40 AM, Philippe Mathieu-Daudé wrote:
> On 8/26/21 5:28 AM, Jason Wang wrote:
>> On Thu, Aug 26, 2021 at 6:43 AM Philippe Mathieu-Daudé
>> <philmd@redhat.com> wrote:
>>>
>>> When a ring queue size is modified, we need to call
>>> virtio_queue_update_rings() to re-init the memory region
>>> caches. Otherwise the region might have outdated memory
>>> size, and later load/store access might trigger an
>>> assertion, such:
>>>
>>> qemu-system-i386: include/exec/memory_ldst_cached.h.inc:30: uint16_t address_space_lduw_le_cached(MemoryRegionCache *, hwaddr, MemTxAttrs, MemTxResult *):
>>> Assertion `addr < cache->len && 2 <= cache->len - addr' failed.
>>> Thread 1 "qemu-system-i38" received signal SIGABRT, Aborted.
>>> 0x00007ffff4d312a2 in raise () from /lib64/libc.so.6
>>> (gdb) bt
>>> #1 0x00007ffff4d1a8a4 in abort () at /lib64/libc.so.6
>>> #4 0x0000555558f2b8ec in address_space_lduw_le_cached (cache=0x61300010a7c0, addr=134, attrs=..., result=0x0) at include/exec/memory_ldst_cached.h.inc:30
>>> #5 0x0000555558f2ac6b in lduw_le_phys_cached (cache=0x61300010a7c0, addr=134) at include/exec/memory_ldst_phys.h.inc:67
>>> #6 0x0000555558f2a3cd in virtio_lduw_phys_cached (vdev=0x62d00003a680, cache=0x61300010a7c0, pa=134) at include/hw/virtio/virtio-access.h:166
>>> #7 0x0000555558f300ea in vring_avail_ring (vq=0x7fffdd55d8a0, i=65) at hw/virtio/virtio.c:326
>>> #8 0x0000555558f33b10 in vring_get_used_event (vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:332
>>> #9 0x0000555558f33677 in virtio_split_should_notify (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:2471
>>> #10 0x0000555558f1859f in virtio_should_notify (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:2523
>>> #11 0x0000555558f188cc in virtio_notify (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:2565
>>> #12 0x0000555557c2bd52 in virtio_input_handle_sts (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/input/virtio-input.c:100
>>> #13 0x0000555558f16df7 in virtio_queue_notify (vdev=0x62d00003a680, n=1) at hw/virtio/virtio.c:2363
>>> #14 0x00005555583f45c0 in virtio_pci_notify_write (opaque=0x62d000032400, addr=7, val=0, size=1) at hw/virtio/virtio-pci.c:1369
>>> #15 0x0000555558b80b04 in memory_region_write_accessor (mr=0x62d000033190, addr=7, value=0x7fffffff8eb0, size=1, shift=0, mask=255, attrs=...) at softmmu/memory.c:492
>>>
>>> Reported-by: Qiuhao Li <Qiuhao.Li@outlook.com>
>>> Fixes: ab223c9518e ("virtio: allow virtio-1 queue layout")
>>> Resolves: https://gitlab.com/qemu-project/qemu/-/issues/302
>>> BugLink: https://bugs.launchpad.net/qemu/+bug/1913510
>>> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
>>> ---
>>> hw/virtio/virtio.c | 1 +
>>> 1 file changed, 1 insertion(+)
>>>
>>> diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
>>> index 874377f37a7..04ffe5f420e 100644
>>> --- a/hw/virtio/virtio.c
>>> +++ b/hw/virtio/virtio.c
>>> @@ -2255,6 +2255,7 @@ void virtio_queue_set_num(VirtIODevice *vdev, int n, int num)
>>> return;
>>> }
>>> vdev->vq[n].vring.num = num;
>>> + virtio_queue_update_rings(vdev, n);
>>> }
>>>
>>
>> Spec said:
>>
>> "
>> The driver MUST configure the other virtqueue fields before enabling
>> the virtqueue with queue_enable.
>> "
>>
>> So I think we should forbid the num to be changed if the virtqueue is ready?
What about virtio_queue_set_addr() and virtio_queue_set_align()?
^ permalink raw reply [flat|nested] 9+ messages in thread* Re: [PATCH] hw/virtio: Update vring after modifying its queue size
2021-08-26 15:16 ` Philippe Mathieu-Daudé
@ 2021-08-30 21:15 ` Michael S. Tsirkin
0 siblings, 0 replies; 9+ messages in thread
From: Michael S. Tsirkin @ 2021-08-30 21:15 UTC (permalink / raw)
To: Philippe Mathieu-Daudé
Cc: Jason Wang, Cornelia Huck, Li Qiang, qemu-devel, Qiuhao Li,
Alexander Bulekov, Stefan Hajnoczi, Paolo Bonzini
On Thu, Aug 26, 2021 at 05:16:03PM +0200, Philippe Mathieu-Daudé wrote:
> On 8/26/21 10:40 AM, Philippe Mathieu-Daudé wrote:
> > On 8/26/21 5:28 AM, Jason Wang wrote:
> >> On Thu, Aug 26, 2021 at 6:43 AM Philippe Mathieu-Daudé
> >> <philmd@redhat.com> wrote:
> >>>
> >>> When a ring queue size is modified, we need to call
> >>> virtio_queue_update_rings() to re-init the memory region
> >>> caches. Otherwise the region might have outdated memory
> >>> size, and later load/store access might trigger an
> >>> assertion, such:
> >>>
> >>> qemu-system-i386: include/exec/memory_ldst_cached.h.inc:30: uint16_t address_space_lduw_le_cached(MemoryRegionCache *, hwaddr, MemTxAttrs, MemTxResult *):
> >>> Assertion `addr < cache->len && 2 <= cache->len - addr' failed.
> >>> Thread 1 "qemu-system-i38" received signal SIGABRT, Aborted.
> >>> 0x00007ffff4d312a2 in raise () from /lib64/libc.so.6
> >>> (gdb) bt
> >>> #1 0x00007ffff4d1a8a4 in abort () at /lib64/libc.so.6
> >>> #4 0x0000555558f2b8ec in address_space_lduw_le_cached (cache=0x61300010a7c0, addr=134, attrs=..., result=0x0) at include/exec/memory_ldst_cached.h.inc:30
> >>> #5 0x0000555558f2ac6b in lduw_le_phys_cached (cache=0x61300010a7c0, addr=134) at include/exec/memory_ldst_phys.h.inc:67
> >>> #6 0x0000555558f2a3cd in virtio_lduw_phys_cached (vdev=0x62d00003a680, cache=0x61300010a7c0, pa=134) at include/hw/virtio/virtio-access.h:166
> >>> #7 0x0000555558f300ea in vring_avail_ring (vq=0x7fffdd55d8a0, i=65) at hw/virtio/virtio.c:326
> >>> #8 0x0000555558f33b10 in vring_get_used_event (vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:332
> >>> #9 0x0000555558f33677 in virtio_split_should_notify (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:2471
> >>> #10 0x0000555558f1859f in virtio_should_notify (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:2523
> >>> #11 0x0000555558f188cc in virtio_notify (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:2565
> >>> #12 0x0000555557c2bd52 in virtio_input_handle_sts (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/input/virtio-input.c:100
> >>> #13 0x0000555558f16df7 in virtio_queue_notify (vdev=0x62d00003a680, n=1) at hw/virtio/virtio.c:2363
> >>> #14 0x00005555583f45c0 in virtio_pci_notify_write (opaque=0x62d000032400, addr=7, val=0, size=1) at hw/virtio/virtio-pci.c:1369
> >>> #15 0x0000555558b80b04 in memory_region_write_accessor (mr=0x62d000033190, addr=7, value=0x7fffffff8eb0, size=1, shift=0, mask=255, attrs=...) at softmmu/memory.c:492
> >>>
> >>> Reported-by: Qiuhao Li <Qiuhao.Li@outlook.com>
> >>> Fixes: ab223c9518e ("virtio: allow virtio-1 queue layout")
> >>> Resolves: https://gitlab.com/qemu-project/qemu/-/issues/302
> >>> BugLink: https://bugs.launchpad.net/qemu/+bug/1913510
> >>> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> >>> ---
> >>> hw/virtio/virtio.c | 1 +
> >>> 1 file changed, 1 insertion(+)
> >>>
> >>> diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
> >>> index 874377f37a7..04ffe5f420e 100644
> >>> --- a/hw/virtio/virtio.c
> >>> +++ b/hw/virtio/virtio.c
> >>> @@ -2255,6 +2255,7 @@ void virtio_queue_set_num(VirtIODevice *vdev, int n, int num)
> >>> return;
> >>> }
> >>> vdev->vq[n].vring.num = num;
> >>> + virtio_queue_update_rings(vdev, n);
> >>> }
> >>>
> >>
> >> Spec said:
> >>
> >> "
> >> The driver MUST configure the other virtqueue fields before enabling
> >> the virtqueue with queue_enable.
> >> "
> >>
> >> So I think we should forbid the num to be changed if the virtqueue is ready?
>
> What about virtio_queue_set_addr() and virtio_queue_set_align()?
Same thing I guess.
--
MST
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] hw/virtio: Update vring after modifying its queue size
2021-08-26 8:40 ` Philippe Mathieu-Daudé
2021-08-26 15:16 ` Philippe Mathieu-Daudé
@ 2021-08-30 21:16 ` Michael S. Tsirkin
1 sibling, 0 replies; 9+ messages in thread
From: Michael S. Tsirkin @ 2021-08-30 21:16 UTC (permalink / raw)
To: Philippe Mathieu-Daudé
Cc: Jason Wang, Cornelia Huck, Li Qiang, qemu-devel, Qiuhao Li,
Alexander Bulekov, Stefan Hajnoczi, Paolo Bonzini
On Thu, Aug 26, 2021 at 10:40:47AM +0200, Philippe Mathieu-Daudé wrote:
> On 8/26/21 5:28 AM, Jason Wang wrote:
> > On Thu, Aug 26, 2021 at 6:43 AM Philippe Mathieu-Daudé
> > <philmd@redhat.com> wrote:
> >>
> >> When a ring queue size is modified, we need to call
> >> virtio_queue_update_rings() to re-init the memory region
> >> caches. Otherwise the region might have outdated memory
> >> size, and later load/store access might trigger an
> >> assertion, such:
> >>
> >> qemu-system-i386: include/exec/memory_ldst_cached.h.inc:30: uint16_t address_space_lduw_le_cached(MemoryRegionCache *, hwaddr, MemTxAttrs, MemTxResult *):
> >> Assertion `addr < cache->len && 2 <= cache->len - addr' failed.
> >> Thread 1 "qemu-system-i38" received signal SIGABRT, Aborted.
> >> 0x00007ffff4d312a2 in raise () from /lib64/libc.so.6
> >> (gdb) bt
> >> #1 0x00007ffff4d1a8a4 in abort () at /lib64/libc.so.6
> >> #4 0x0000555558f2b8ec in address_space_lduw_le_cached (cache=0x61300010a7c0, addr=134, attrs=..., result=0x0) at include/exec/memory_ldst_cached.h.inc:30
> >> #5 0x0000555558f2ac6b in lduw_le_phys_cached (cache=0x61300010a7c0, addr=134) at include/exec/memory_ldst_phys.h.inc:67
> >> #6 0x0000555558f2a3cd in virtio_lduw_phys_cached (vdev=0x62d00003a680, cache=0x61300010a7c0, pa=134) at include/hw/virtio/virtio-access.h:166
> >> #7 0x0000555558f300ea in vring_avail_ring (vq=0x7fffdd55d8a0, i=65) at hw/virtio/virtio.c:326
> >> #8 0x0000555558f33b10 in vring_get_used_event (vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:332
> >> #9 0x0000555558f33677 in virtio_split_should_notify (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:2471
> >> #10 0x0000555558f1859f in virtio_should_notify (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:2523
> >> #11 0x0000555558f188cc in virtio_notify (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:2565
> >> #12 0x0000555557c2bd52 in virtio_input_handle_sts (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/input/virtio-input.c:100
> >> #13 0x0000555558f16df7 in virtio_queue_notify (vdev=0x62d00003a680, n=1) at hw/virtio/virtio.c:2363
> >> #14 0x00005555583f45c0 in virtio_pci_notify_write (opaque=0x62d000032400, addr=7, val=0, size=1) at hw/virtio/virtio-pci.c:1369
> >> #15 0x0000555558b80b04 in memory_region_write_accessor (mr=0x62d000033190, addr=7, value=0x7fffffff8eb0, size=1, shift=0, mask=255, attrs=...) at softmmu/memory.c:492
> >>
> >> Reported-by: Qiuhao Li <Qiuhao.Li@outlook.com>
> >> Fixes: ab223c9518e ("virtio: allow virtio-1 queue layout")
> >> Resolves: https://gitlab.com/qemu-project/qemu/-/issues/302
> >> BugLink: https://bugs.launchpad.net/qemu/+bug/1913510
> >> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> >> ---
> >> hw/virtio/virtio.c | 1 +
> >> 1 file changed, 1 insertion(+)
> >>
> >> diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
> >> index 874377f37a7..04ffe5f420e 100644
> >> --- a/hw/virtio/virtio.c
> >> +++ b/hw/virtio/virtio.c
> >> @@ -2255,6 +2255,7 @@ void virtio_queue_set_num(VirtIODevice *vdev, int n, int num)
> >> return;
> >> }
> >> vdev->vq[n].vring.num = num;
> >> + virtio_queue_update_rings(vdev, n);
> >> }
> >>
> >
> > Spec said:
> >
> > "
> > The driver MUST configure the other virtqueue fields before enabling
> > the virtqueue with queue_enable.
> > "
> >
> > So I think we should forbid the num to be changed if the virtqueue is ready?
>
> Alright. virtio_pci_common_write() doesn't report errors although.
It can't - just log guest error and ignore. Maybe set needs_reset ...
--
MST
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] hw/virtio: Update vring after modifying its queue size
2021-08-25 22:42 [PATCH] hw/virtio: Update vring after modifying its queue size Philippe Mathieu-Daudé
2021-08-25 22:47 ` Philippe Mathieu-Daudé
2021-08-26 3:28 ` Jason Wang
@ 2021-09-02 14:56 ` Stefan Hajnoczi
2021-09-14 11:12 ` Alexander Bulekov
3 siblings, 0 replies; 9+ messages in thread
From: Stefan Hajnoczi @ 2021-09-02 14:56 UTC (permalink / raw)
To: Philippe Mathieu-Daudé
Cc: Michael S. Tsirkin, Jason Wang, Cornelia Huck, Li Qiang,
qemu-devel, Qiuhao Li, Alexander Bulekov, Paolo Bonzini
[-- Attachment #1: Type: text/plain, Size: 3393 bytes --]
On Thu, Aug 26, 2021 at 12:42:56AM +0200, Philippe Mathieu-Daudé wrote:
> When a ring queue size is modified, we need to call
> virtio_queue_update_rings() to re-init the memory region
> caches. Otherwise the region might have outdated memory
> size, and later load/store access might trigger an
> assertion, such:
>
> qemu-system-i386: include/exec/memory_ldst_cached.h.inc:30: uint16_t address_space_lduw_le_cached(MemoryRegionCache *, hwaddr, MemTxAttrs, MemTxResult *):
> Assertion `addr < cache->len && 2 <= cache->len - addr' failed.
> Thread 1 "qemu-system-i38" received signal SIGABRT, Aborted.
> 0x00007ffff4d312a2 in raise () from /lib64/libc.so.6
> (gdb) bt
> #1 0x00007ffff4d1a8a4 in abort () at /lib64/libc.so.6
> #4 0x0000555558f2b8ec in address_space_lduw_le_cached (cache=0x61300010a7c0, addr=134, attrs=..., result=0x0) at include/exec/memory_ldst_cached.h.inc:30
> #5 0x0000555558f2ac6b in lduw_le_phys_cached (cache=0x61300010a7c0, addr=134) at include/exec/memory_ldst_phys.h.inc:67
> #6 0x0000555558f2a3cd in virtio_lduw_phys_cached (vdev=0x62d00003a680, cache=0x61300010a7c0, pa=134) at include/hw/virtio/virtio-access.h:166
> #7 0x0000555558f300ea in vring_avail_ring (vq=0x7fffdd55d8a0, i=65) at hw/virtio/virtio.c:326
> #8 0x0000555558f33b10 in vring_get_used_event (vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:332
> #9 0x0000555558f33677 in virtio_split_should_notify (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:2471
> #10 0x0000555558f1859f in virtio_should_notify (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:2523
> #11 0x0000555558f188cc in virtio_notify (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:2565
> #12 0x0000555557c2bd52 in virtio_input_handle_sts (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/input/virtio-input.c:100
> #13 0x0000555558f16df7 in virtio_queue_notify (vdev=0x62d00003a680, n=1) at hw/virtio/virtio.c:2363
> #14 0x00005555583f45c0 in virtio_pci_notify_write (opaque=0x62d000032400, addr=7, val=0, size=1) at hw/virtio/virtio-pci.c:1369
> #15 0x0000555558b80b04 in memory_region_write_accessor (mr=0x62d000033190, addr=7, value=0x7fffffff8eb0, size=1, shift=0, mask=255, attrs=...) at softmmu/memory.c:492
>
> Reported-by: Qiuhao Li <Qiuhao.Li@outlook.com>
> Fixes: ab223c9518e ("virtio: allow virtio-1 queue layout")
> Resolves: https://gitlab.com/qemu-project/qemu/-/issues/302
> BugLink: https://bugs.launchpad.net/qemu/+bug/1913510
> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> ---
> hw/virtio/virtio.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
> index 874377f37a7..04ffe5f420e 100644
> --- a/hw/virtio/virtio.c
> +++ b/hw/virtio/virtio.c
> @@ -2255,6 +2255,7 @@ void virtio_queue_set_num(VirtIODevice *vdev, int n, int num)
> return;
> }
> vdev->vq[n].vring.num = num;
> + virtio_queue_update_rings(vdev, n);
> }
Can this line in hw/virtio/virtio-mmio.c be removed now?
case VIRTIO_MMIO_QUEUE_NUM:
trace_virtio_mmio_queue_write(value, VIRTQUEUE_MAX_SIZE);
virtio_queue_set_num(vdev, vdev->queue_sel, value);
if (proxy->legacy) {
virtio_queue_update_rings(vdev, vdev->queue_sel);
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Stefan
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^ permalink raw reply [flat|nested] 9+ messages in thread* Re: [PATCH] hw/virtio: Update vring after modifying its queue size
2021-08-25 22:42 [PATCH] hw/virtio: Update vring after modifying its queue size Philippe Mathieu-Daudé
` (2 preceding siblings ...)
2021-09-02 14:56 ` Stefan Hajnoczi
@ 2021-09-14 11:12 ` Alexander Bulekov
3 siblings, 0 replies; 9+ messages in thread
From: Alexander Bulekov @ 2021-09-14 11:12 UTC (permalink / raw)
To: Philippe Mathieu-Daudé
Cc: Michael S. Tsirkin, Jason Wang, Cornelia Huck, Li Qiang,
qemu-devel, Qiuhao Li, Stefan Hajnoczi, Paolo Bonzini
On 210826 0042, Philippe Mathieu-Daudé wrote:
> When a ring queue size is modified, we need to call
> virtio_queue_update_rings() to re-init the memory region
> caches. Otherwise the region might have outdated memory
> size, and later load/store access might trigger an
> assertion, such:
>
> qemu-system-i386: include/exec/memory_ldst_cached.h.inc:30: uint16_t address_space_lduw_le_cached(MemoryRegionCache *, hwaddr, MemTxAttrs, MemTxResult *):
> Assertion `addr < cache->len && 2 <= cache->len - addr' failed.
> Thread 1 "qemu-system-i38" received signal SIGABRT, Aborted.
> 0x00007ffff4d312a2 in raise () from /lib64/libc.so.6
> (gdb) bt
> #1 0x00007ffff4d1a8a4 in abort () at /lib64/libc.so.6
> #4 0x0000555558f2b8ec in address_space_lduw_le_cached (cache=0x61300010a7c0, addr=134, attrs=..., result=0x0) at include/exec/memory_ldst_cached.h.inc:30
> #5 0x0000555558f2ac6b in lduw_le_phys_cached (cache=0x61300010a7c0, addr=134) at include/exec/memory_ldst_phys.h.inc:67
> #6 0x0000555558f2a3cd in virtio_lduw_phys_cached (vdev=0x62d00003a680, cache=0x61300010a7c0, pa=134) at include/hw/virtio/virtio-access.h:166
> #7 0x0000555558f300ea in vring_avail_ring (vq=0x7fffdd55d8a0, i=65) at hw/virtio/virtio.c:326
> #8 0x0000555558f33b10 in vring_get_used_event (vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:332
> #9 0x0000555558f33677 in virtio_split_should_notify (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:2471
> #10 0x0000555558f1859f in virtio_should_notify (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:2523
> #11 0x0000555558f188cc in virtio_notify (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:2565
> #12 0x0000555557c2bd52 in virtio_input_handle_sts (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/input/virtio-input.c:100
> #13 0x0000555558f16df7 in virtio_queue_notify (vdev=0x62d00003a680, n=1) at hw/virtio/virtio.c:2363
> #14 0x00005555583f45c0 in virtio_pci_notify_write (opaque=0x62d000032400, addr=7, val=0, size=1) at hw/virtio/virtio-pci.c:1369
> #15 0x0000555558b80b04 in memory_region_write_accessor (mr=0x62d000033190, addr=7, value=0x7fffffff8eb0, size=1, shift=0, mask=255, attrs=...) at softmmu/memory.c:492
>
> Reported-by: Qiuhao Li <Qiuhao.Li@outlook.com>
> Fixes: ab223c9518e ("virtio: allow virtio-1 queue layout")
> Resolves: https://gitlab.com/qemu-project/qemu/-/issues/302
> BugLink: https://bugs.launchpad.net/qemu/+bug/1913510
OSS-Fuzz found ways to trigger assertion failure for virtio-{rng,
serial, scsi, balloon, 9p}. Would it be useful to have qtest reproducers
for these?
-Alex
> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> ---
> hw/virtio/virtio.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
> index 874377f37a7..04ffe5f420e 100644
> --- a/hw/virtio/virtio.c
> +++ b/hw/virtio/virtio.c
> @@ -2255,6 +2255,7 @@ void virtio_queue_set_num(VirtIODevice *vdev, int n, int num)
> return;
> }
> vdev->vq[n].vring.num = num;
> + virtio_queue_update_rings(vdev, n);
> }
>
> VirtQueue *virtio_vector_first_queue(VirtIODevice *vdev, uint16_t vector)
> --
> 2.31.1
>
^ permalink raw reply [flat|nested] 9+ messages in thread