From c98b2cc29af8e84e7364b53e9bb4cc7cfaf62555 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Tue, 27 Dec 2011 18:52:16 +0100 Subject: [PATCH] block: remove WARN_ON_ONCE() in exit_io_context() 6e736be7 "block: make ioc get/put interface more conventional and fix race on alloction" added WARN_ON_ONCE() in exit_io_context() which triggers if !PF_EXITING. All tasks hitting exit_io_context() from task exit should have PF_EXITING set but task struct tearing down after fork failure calls into the function without PF_EXITING, triggering the condition. WARNING: at block/blk-ioc.c:234 exit_io_context+0x40/0x92() Pid: 17090, comm: trinity Not tainted 3.2.0-rc6-next-20111222-sasha-dirty #77 Call Trace: [] warn_slowpath_common+0x8f/0xb2 [] warn_slowpath_null+0x18/0x1a [] exit_io_context+0x40/0x92 [] copy_process+0x126f/0x1453 [] do_fork+0x120/0x3e9 [] sys_clone+0x26/0x28 [] stub_clone+0x13/0x20 ---[ end trace a2e4eb670b375238 ]--- Reported-by: Sasha Levin Signed-off-by: Tejun Heo Signed-off-by: Jens Axboe --- block/blk-ioc.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/block/blk-ioc.c b/block/blk-ioc.c index 33fae7df16a0..27a06e00eaec 100644 --- a/block/blk-ioc.c +++ b/block/blk-ioc.c @@ -230,9 +230,6 @@ void exit_io_context(struct task_struct *task) { struct io_context *ioc; - /* PF_EXITING prevents new io_context from being attached to @task */ - WARN_ON_ONCE(!(current->flags & PF_EXITING)); - task_lock(task); ioc = task->io_context; task->io_context = NULL;