From: "Michael S. Tsirkin" <mst@redhat.com>
To: Zhang Tianci <zhangtianci.1997@bytedance.com>
Cc: jasowang@redhat.com, xuanzhuo@linux.alibaba.com,
eperezma@redhat.com, virtualization@lists.linux.dev,
xieyongji@bytedance.com
Subject: Re: virtio_pci: Question about virtio_pci kernel module refcnt
Date: Wed, 22 Oct 2025 07:31:29 -0400 [thread overview]
Message-ID: <20251022073015-mutt-send-email-mst@kernel.org> (raw)
In-Reply-To: <CAP4dvsfZEo+1+O8tpLFFh=s-fEFaMRu2+mQ3F=LJmjoEHyZXMw@mail.gmail.com>
On Wed, Oct 22, 2025 at 07:21:45PM +0800, Zhang Tianci wrote:
> Hi,
> I noticed that the reference count of the virtio_pci kernel module
> in the VM is always 0, even though there are at least two
> virtio block devices and one virtiofs device in the VM.
>
> Using rmmod virtio_pci can unload the virtio_pci module,
> but this renders the virtio block devices unusable.
it removes them. you can put it back in and you will
get devices again.
> I wonder if this result is expected? Why don't the virtio block devices
> and virtiofs device hold a reference count to the virtio_pci kernel module?
because they don't have to.
--
MST
next prev parent reply other threads:[~2025-10-22 11:31 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-10-22 11:21 virtio_pci: Question about virtio_pci kernel module refcnt Zhang Tianci
2025-10-22 11:31 ` Michael S. Tsirkin [this message]
2025-10-23 2:34 ` [External] " Zhang Tianci
2025-10-24 1:53 ` Jason Wang
2025-10-24 2:34 ` Zhang Tianci
2025-10-24 4:00 ` Jason Wang
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