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Tsirkin" To: Xianting Tian Cc: arei.gonglei@huawei.com, jasowang@redhat.com, xuanzhuo@linux.alibaba.com, herbert@gondor.apana.org.au, davem@davemloft.net, amit@kernel.org, arnd@arndb.de, gregkh@linuxfoundation.org, marcel@holtmann.org, johan.hedberg@gmail.com, luiz.dentz@gmail.com, linux-bluetooth@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/3] virtio_console: fixup potential cpu stall when free unused bufs Message-ID: <20230609120332-mutt-send-email-mst@kernel.org> References: <20230609131817.712867-1-xianting.tian@linux.alibaba.com> <20230609131817.712867-3-xianting.tian@linux.alibaba.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230609131817.712867-3-xianting.tian@linux.alibaba.com> Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org On Fri, Jun 09, 2023 at 09:18:16PM +0800, Xianting Tian wrote: > Cpu stall issue may happen if device is configured with multi queues > and large queue depth, so fix it. "may happen" is ambigous. So is this: "for virtio-net we were getting stall on CPU was observed message, this driver is similar so theoretically the same logic applies" or is this "the following error occured: ..... " ? > Signed-off-by: Xianting Tian > --- > drivers/char/virtio_console.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c > index b65c809a4e97..5ec4cf4ea919 100644 > --- a/drivers/char/virtio_console.c > +++ b/drivers/char/virtio_console.c > @@ -1935,6 +1935,7 @@ static void remove_vqs(struct ports_device *portdev) > flush_bufs(vq, true); > while ((buf = virtqueue_detach_unused_buf(vq))) > free_buf(buf, true); > + cond_resched(); > } > portdev->vdev->config->del_vqs(portdev->vdev); > kfree(portdev->in_vqs); > -- > 2.17.1