Re: [PATCH] vhost/scsi: Use safe iteration in vhost_scsi_complete_cmd_work()

From: Byungchul Park
Date: Wed Nov 15 2017 - 18:53:10 EST


On Thu, Nov 09, 2017 at 09:17:29AM +0900, Byungchul Park wrote:
> I am sorry for having made a mistake on it.

Hello Nicholas,

Please consider this patch urgently. I'm sorry for having changed the
original behavior with the previous patch.

The safe version of llist API should be used to keep the original
behavior.

Thanks,
Byungchul

> -----8<-----
> >From ba9a0f76dffceffa4fa3aa2d9be49cdb0d9b7d4f Mon Sep 17 00:00:00 2001
> From: Byungchul Park <byungchul.park@xxxxxxx>
> Date: Thu, 9 Nov 2017 09:00:21 +0900
> Subject: [PATCH] vhost/scsi: Use safe iteration in vhost_scsi_complete_cmd_work()
>
> The following patch changed the behavior which originally did safe
> iteration. Make it safe as it was.
>
> 12bdcbd539c6327c09da0503c674733cb2d82cb5
> vhost/scsi: Don't reinvent the wheel but use existing llist API
>
> Signed-off-by: Byungchul Park <byungchul.park@xxxxxxx>
> ---
> drivers/vhost/scsi.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c
> index 046f6d2..46539ca 100644
> --- a/drivers/vhost/scsi.c
> +++ b/drivers/vhost/scsi.c
> @@ -519,7 +519,7 @@ static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
> vs_completion_work);
> DECLARE_BITMAP(signal, VHOST_SCSI_MAX_VQ);
> struct virtio_scsi_cmd_resp v_rsp;
> - struct vhost_scsi_cmd *cmd;
> + struct vhost_scsi_cmd *cmd, *t;
> struct llist_node *llnode;
> struct se_cmd *se_cmd;
> struct iov_iter iov_iter;
> @@ -527,7 +527,7 @@ static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
>
> bitmap_zero(signal, VHOST_SCSI_MAX_VQ);
> llnode = llist_del_all(&vs->vs_completion_list);
> - llist_for_each_entry(cmd, llnode, tvc_completion_list) {
> + llist_for_each_entry_safe(cmd, t, llnode, tvc_completion_list) {
> se_cmd = &cmd->tvc_se_cmd;
>
> pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__,
> --
> 1.9.1