All of lore.kernel.org
 help / color / mirror / Atom feed
From: Steve Wise <swise-7bPotxP6k4+P2YhJcF5u+vpXobYPEAuW@public.gmane.org>
To: Roland Dreier <roland-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Cc: linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Subject: Re: [PATCH] RDMA/cxgb4: don't declare wr_wait objects on the stack.
Date: Mon, 16 May 2011 10:56:45 -0500	[thread overview]
Message-ID: <4DD1493D.3060401@opengridcomputing.com> (raw)
In-Reply-To: <BANLkTimGzzo1xDTvApAVxvv4C8WcYuCdUA-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>

On 05/16/2011 10:53 AM, Roland Dreier wrote:
> On Mon, May 16, 2011 at 8:18 AM, Steve Wise<swise-7bPotxP6k4+P2YhJcF5u+vpXobYPEAuW@public.gmane.org>  wrote:
>> Roland, I need to recall this patch.  It appears to have some problem.
> Good thing I didn't apply it yet.
>
> I did think it should be possible to declare wait objects on the stack... the
> origin of completions was to handle exactly that issue; the older semaphore
> structure was vulnerable to the wakeup after free, but completions handle
> that.  But I didn't look at the cxgb4 code at all...

I'm pretty sure the race exists as described in my commit comment.  And I don't see how the wait object code could avoid 
this issue.  Unless I'm just all wrong. :)


--
To unsubscribe from this list: send the line "unsubscribe linux-rdma" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

  parent reply	other threads:[~2011-05-16 15:56 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-05-13 18:37 [PATCH] RDMA/cxgb4: don't declare wr_wait objects on the stack Steve Wise
     [not found] ` <20110513183727.32157.8873.stgit-T4OLL4TyM9aNDNWfRnPdfg@public.gmane.org>
2011-05-16 15:18   ` Steve Wise
     [not found]     ` <4DD14036.9050704-7bPotxP6k4+P2YhJcF5u+vpXobYPEAuW@public.gmane.org>
2011-05-16 15:53       ` Roland Dreier
     [not found]         ` <BANLkTimGzzo1xDTvApAVxvv4C8WcYuCdUA-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2011-05-16 15:56           ` Steve Wise [this message]
     [not found]             ` <4DD1493D.3060401-7bPotxP6k4+P2YhJcF5u+vpXobYPEAuW@public.gmane.org>
2011-05-16 16:05               ` Steve Wise
     [not found]                 ` <4DD14B2D.9090104-7bPotxP6k4+P2YhJcF5u+vpXobYPEAuW@public.gmane.org>
2011-05-16 16:47                   ` Steve Wise

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=4DD1493D.3060401@opengridcomputing.com \
    --to=swise-7bpotxp6k4+p2yhjcf5u+vpxobypeauw@public.gmane.org \
    --cc=linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
    --cc=roland-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.