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

From: Michael S. Tsirkin
Date: Wed Nov 15 2017 - 20:31:06 EST


On Thu, Nov 16, 2017 at 08:52:39AM +0900, Byungchul Park wrote:
> 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

I have included this patch in my tree.

> > -----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