Re: [PATCH block/for-3.3/core] block: an exiting task should be allowed to create io_context
From: Tejun Heo <tj@kernel.org>
Date: 2012-01-03 20:09:15
Also in:
linux-next, linux-scsi, lkml
On Tue, Jan 03, 2012 at 09:59:22AM -0800, Tejun Heo wrote:
That should have been service tree. I couldn't find more missing removals other than the one Shaohua's patch already fixed. Close cooperator selection in cfq_select_queue() seems suspicious tho. I can't see what prevents it from returning an empty coopeator cfqq. I'm trying to verify whether that's the case. Will update when I know more.
While testing, found another bug. Redzone: 0x9f911029d74e35b/0x9f911029d74e35b. Last user: [<ffffffff813a82ee>](cfq_put_queue+0x7e/0xd0) 070: e8 32 ab 1d 00 88 ff ff e8 32 ab 1d 00 88 ff ff .2.......2...... Prev obj: start=ffff88001dab3178, len=232 Redzone: 0x9f911029d74e35b/0x9f911029d74e35b. Last user: [<ffffffff813a82ee>](cfq_put_queue+0x7e/0xd0) 000: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk 010: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Next obj: start=ffff88001dab3378, len=232 Redzone: 0xd84156c5635688c0/0xd84156c5635688c0. Last user: [<ffffffff813a8e53>](cfq_get_queue+0x153/0x670) 000: 02 00 00 00 21 01 00 00 e0 c9 b1 1d 00 88 ff ff ....!........... 010: 89 96 ae 18 00 88 ff ff 00 00 00 00 00 00 00 00 ................ The field at 0x70 which is being updated after being freed is cfqq->fifo. Interestingly, it didn't lead to any visible failure. Thanks. -- tejun