From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robin Holt Date: Sat, 19 May 2007 02:08:32 +0000 Subject: Re: [PATCH] get_wchan on running task sometimes MCAs the machine. Message-Id: <20070519020832.GA26643@lnx-holt.americas.sgi.com> List-Id: References: <20070517111651.GA760@lnx-holt.americas.sgi.com> In-Reply-To: <20070517111651.GA760@lnx-holt.americas.sgi.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org On Fri, May 18, 2007 at 04:01:21PM -0700, Luck, Tony wrote: > If the problem *only* occurs when trying to get_wchan on the > current task (a futile endevour) then the original patch > should be fine all by itself ... there are no races involved > the current task is going to remain in TASK_RUNNING state at > any point that it happens to look at itself. The problem I was seeing was only on the current task, but we could have two seperate threads creating that situation. I could certain see the argument for adding the sanity checks to the current unwind code or verifying that libunwind does not suffer the same race conditions. I will leave it to your discretion. Thanks, Robin