From: Zhang Tianci Date: Thu, 26 Feb 2026 11:55:49 +0000 (+0800) Subject: vduse: Requeue failed read to send_list head X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=373ec43ded742b2f3aecf14731ffe1a57f438f38;p=thirdparty%2Flinux.git vduse: Requeue failed read to send_list head When copy_to_iter() fails in vduse_dev_read_iter(), put the message back at the head of send_list to preserve FIFO ordering and retry the oldest pending request first. Fixes: c8a6153b6c59 ("vduse: Introduce VDUSE - vDPA Device in Userspace") Reported-by: Michael S. Tsirkin Suggested-by: Xie Yongji Signed-off-by: Zhang Tianci Reviewed-by: Xie Yongji Acked-by: Jason Wang Acked-by: Eugenio Pérez Acked-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin Message-ID: <20260226115550.1814-2-zhangtianci.1997@bytedance.com> --- diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c index d5c34260ed68..a479fef535ac 100644 --- a/drivers/vdpa/vdpa_user/vduse_dev.c +++ b/drivers/vdpa/vdpa_user/vduse_dev.c @@ -221,6 +221,12 @@ static void vduse_enqueue_msg(struct list_head *head, list_add_tail(&msg->list, head); } +static void vduse_enqueue_msg_head(struct list_head *head, + struct vduse_dev_msg *msg) +{ + list_add(&msg->list, head); +} + static void vduse_dev_broken(struct vduse_dev *dev) { struct vduse_dev_msg *msg, *tmp; @@ -387,7 +393,7 @@ static ssize_t vduse_dev_read_iter(struct kiocb *iocb, struct iov_iter *to) spin_lock(&dev->msg_lock); if (ret != size) { ret = -EFAULT; - vduse_enqueue_msg(&dev->send_list, msg); + vduse_enqueue_msg_head(&dev->send_list, msg); goto unlock; } vduse_enqueue_msg(&dev->recv_list, msg);