David Hildenbrand
2022-Nov-28 08:22 UTC
[PATCH 2/4] virtio-mem: Fix probe failed when modprobe virtio_mem
On 28.11.22 03:10, Li Zetao wrote:> When doing the following test steps, an error was found: > step 1: modprobe virtio_mem succeeded > # modprobe virtio_mem <-- OK > > step 2: fault injection in virtio_mem_init() > # modprobe -r virtio_mem <-- OK > # ... > CPU: 0 PID: 1837 Comm: modprobe Not tainted > 6.1.0-rc6-00285-g6a1e40c4b995-dirty > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) > Call Trace: > <TASK> > should_fail.cold+0x5/0x1f > ... > virtio_mem_init_hotplug+0x9ae/0xe57 [virtio_mem] > virtio_mem_init.cold+0x327/0x339 [virtio_mem] > virtio_mem_probe+0x48e/0x910 [virtio_mem] > virtio_dev_probe+0x608/0xae0 > ... > </TASK> > virtio_mem virtio4: could not reserve device region > virtio_mem: probe of virtio4 failed with error -16 > > step 3: modprobe virtio_net failedvirtio_net ?> # modprobe virtio_mem <-- failed > virtio_mem: probe of virtio4 failed with error -16 > > The root cause of the problem is that the virtqueues are not > stopped on the error handling path when virtio_mem_init() > fails in virtio_mem_probe(), resulting in an error "-ENOENT" > returned in the next modprobe call in setup_vq(). > > virtio_pci_modern_device uses virtqueues to send or > receive message, and "queue_enable" records whether the > queues are available. In vp_modern_find_vqs(), all queues > will be selected and activated, but once queues are enabled > there is no way to go back except reset. > > Fix it by reset virtio device on error handling path. After > virtio_mem_init_vq() succeeded, all virtqueues should be > stopped on error handling path. > > Fixes: 1fcf0512c9c8 ("virtio_pci: modern driver")That commit is from 2014. virtio-mem was merged in 2020 Fixes: 5f1f79bbc9e2 ("virtio-mem: Paravirtualized memory hotplug")> Signed-off-by: Li Zetao <lizetao1 at huawei.com> > --- > drivers/virtio/virtio_mem.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/virtio/virtio_mem.c b/drivers/virtio/virtio_mem.c > index 0c2892ec6817..c7f09c2ce982 100644 > --- a/drivers/virtio/virtio_mem.c > +++ b/drivers/virtio/virtio_mem.c > @@ -2793,6 +2793,7 @@ static int virtio_mem_probe(struct virtio_device *vdev) > > return 0; > out_del_vq: > + virtio_reset_device(vdev); > vdev->config->del_vqs(vdev); > out_free_vm: > kfree(vm);Apart from that Reviewed-by: David Hildenbrand <david at redhat.com> -- Thanks, David / dhildenb