From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nathan Lynch Subject: Re: bugs with ckpt-v15-dev Date: Mon, 18 May 2009 18:02:11 -0500 Message-ID: References: <20090518211041.GA20781@us.ibm.com> <20090518223919.GA24826@us.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20090518223919.GA24826-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org> (Serge E. Hallyn's message of "Mon\, 18 May 2009 17\:39\:19 -0500") List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: "Serge E. Hallyn" Cc: Containers List-Id: containers.vger.kernel.org "Serge E. Hallyn" writes: > Quoting Nathan Lynch (ntl-e+AXbWqSrlAAvxtiuMwx3w@public.gmane.org): >> "Serge E. Hallyn" writes: >> >> > Quoting Nathan Lynch (ntl-e+AXbWqSrlAAvxtiuMwx3w@public.gmane.org): >> >> Last commit is ed3b275 "allow error string during checkpoint while >> >> holding a spinlock". >> >> >> >> # bash -c 'exec <&- >&- 2>&- ; while : ; do : ; done' & >> >> [1] 2269 >> >> # ckpt $! > /tmp/bash.ckpt >> >> >> >> BUG: sleeping function called from invalid context at mm/slub.c:1595 >> > >> > Yeah, not only does ckpt_write_err() get called under task_lock, but >> > the fn returns without ver doing put_task_struct. (I'd generate and >> > send the quick trivial patch, but my git tree is in a bit of a debugme >> > state right now) >> >> Would prefer to just rip that thing out, it's cost me more trouble then >> it's worth. > > Which thing - CHECKPOINT_SUBTREE, freezer check, or ckpt_write_err? ckpt_write_err. I've yet to witness it perform its intended function without triggering a WARN_ON or BUG. >> > Now mind you this shows that your ckpt program isn't sending >> > CHECKPOINT_SUBTREE with flags. >> >> I don't follow. There is "user error" here in that I'm not freezing the >> task before checkpointing[1], but my ckpt command is passing the subtree >> flag (0x4) afaict: >> >> SYS_335(0x9ec, 0x1, 0x4, 0xbfdc6200, 0[2542:c/r:may_checkpoint_task] check 2540 > > Oh, it's the freezer test in may_checkpoint_task you're getting the > error on? (in my git tree I'd commented that one out temporarily so I > just assumed it was the subtree check in get_container :) Yes, the frozen test is failing, afaik.