Andrew, Would you like to merge the patch to your MM tree?
Yanmin >-----Original Message----- >From: Peter Zijlstra [mailto:pet...@infradead.org] >Sent: Friday, May 03, 2013 6:42 PM >To: Wang, Biao >Cc: a...@linux-foundation.org; linux-kernel@vger.kernel.org; >mi...@redhat.com; Zhang, Yanmin; moc...@digitalimplant.org >Subject: Re: [PATCH] klist: del waiter from klist_remove_waiters before wakeup >waitting process > >On Fri, May 03, 2013 at 03:06:36PM +0800, wangbiao wrote: >> From: "wang, biao" <biao.w...@intel.com> >> Date: Fri, 3 May 2013 14:18:34 +0800 >> Subject: [PATCH] klist: del waiter from klist_remove_waiters before >> wakeup waitting process >> >> There is a race between klist_remove and klist_release. klist_remove >> uses a local var waiter saved on stack. When klist_release calls >> wake_up_process(waiter->process) to wake up the waiter, waiter might >> run immediately and reuse the stack. Then, klist_release calls >> list_del(&waiter->list) to change previous wait data and cause prior >> waiter thread corrupt. >> >> The patch fixes it against kernel 3.9. > > >I've never seen that code before in my life; but after a quick look you appear >to >be completely right. > >> Signed-off-by: wang, biao <biao.w...@intel.com> > >Acked-by: Peter Zijlstra <a.p.zijls...@chello.nl> > >> --- >> lib/klist.c | 2 +- >> 1 files changed, 1 insertions(+), 1 deletions(-) >> >> diff --git a/lib/klist.c b/lib/klist.c index 0874e41..358a368 100644 >> --- a/lib/klist.c >> +++ b/lib/klist.c >> @@ -193,10 +193,10 @@ static void klist_release(struct kref *kref) >> if (waiter->node != n) >> continue; >> >> + list_del(&waiter->list); >> waiter->woken = 1; >> mb(); >> wake_up_process(waiter->process); >> - list_del(&waiter->list); >> } >> spin_unlock(&klist_remove_lock); >> knode_set_klist(n, NULL); >> -- >> 1.7.6 >> >> >> -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
