From mboxrd@z Thu Jan 1 00:00:00 1970 From: "JWM" Date: Thu, 25 Jan 2007 21:49:10 +0000 Subject: Re: Spinlock bug?? Message-Id: <001d01c740ca$a5fe0cd0$7401a8c0@Maelstrom> List-Id: References: <003e01c73fd8$6a46f730$7401a8c0@Maelstrom> In-Reply-To: <003e01c73fd8$6a46f730$7401a8c0@Maelstrom> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org Simon; I've looked at the code and the function that calls cpuset_set_cpus_affinity does a get_task. That bumps the usage count and should protect from an exiting process doing evil - shouldn't it? So the sched_setaffinity locks, bumps the task useage and then unlocks and calls cpuset_set_cpus_affinity. The in the Bull code cpuset_set_cpuaffinity takes a spin lock on the structure and then (potentially) moves it to another CPU. It doesn't look like a change is required other than removing the lock in cpuset_set_cpus_affinity. Is there a possible race here I'm missing? ....JW ----- Original Message ----- From: "Simon Derr" To: "JWM" Cc: ; "Philippe Garrigues" Sent: Thursday, January 25, 2007 3:12 AM Subject: Re: Spinlock bug?? >> Hi all; >> I'm working on a Bull - 8 way ia64 system running a RedHat variant of >> 2.6.17. >> I keep getting a spin lock bug and dump , attached. > > Hello, > > If you are running a Bull Linux kernel, I suggest that you contact > directly Bull for this kind of issues. We have added a few custom patches > that could hardly be adressed by other people from this list. > > That being said, I'm going to see what's going on in this particular case. > You're probably right. > > Simon. > > > > - > To unsubscribe from this list: send the line "unsubscribe linux-ia64" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >