Date: Sat, 26 Jan 2008 14:09:35 +0100 From: "Attilio Rao" <attilio@freebsd.org> To: "Scot Hetzel" <swhetzel@gmail.com> Cc: freebsd-current@freebsd.org Subject: Re: panic: System call lstat returning with 1 locks held Message-ID: <3bbf2fe10801260509o12f7d5dof399a751ef48e5c7@mail.gmail.com> In-Reply-To: <790a9fff0801252015l34f524d1k704fa0accffe2545@mail.gmail.com> References: <790a9fff0801150552l542a4238ofc12efe5fdb45fc2@mail.gmail.com> <20080115143924.GB57756@deviant.kiev.zoral.com.ua> <20080124122808.GA15600@freefall.freebsd.org> <3bbf2fe10801240518i6e18b2f5w84de652d4170c95b@mail.gmail.com> <790a9fff0801252015l34f524d1k704fa0accffe2545@mail.gmail.com>
next in thread | previous in thread | raw e-mail | index | archive | help
2008/1/26, Scot Hetzel <swhetzel@gmail.com>: > On 1/24/08, Attilio Rao <attilio@freebsd.org> wrote: > > 2008/1/24, Yar Tikhiy <yar@freebsd.org>: > > > On Tue, Jan 15, 2008 at 04:39:24PM +0200, Kostik Belousov wrote: > > > > > > > > I think this could be related to the recent vn_lock()/VOP_LOCK() KPI changes. > > > > Please, add DEBUG_VFS_LOCKS to the kernel config, and do the > > > > show lockedvnods > > > > from the ddb prompt when the panic occurs. The witness does not track > > > > the lockmgr locks. > > > > > > I think I'm seeing the same panic on UFS. It's rather nasty: I > > > cannot rebuild CURRENT natively due to it so I have to build it > > > under 6-STABLE. My favourite way to trigger the panic reliably is > > > running `make install' in a simple port directory, e.g., portmaster, > > > but my system also panics during daily scripts run and, as already > > > said, if trying to build world. > > > > Yar, > > as it seems reproducible for you, can you please add this patch to the tree: > > http://www.freebsd.org/~attilio/debug_tdlocks.diff > > > > compile your kernel with: > > options KTR > > options KTR_COMPILE=(KTR_SPARE2) > > options KTR_MASK=(KTR_SPARE2) > > options KTR_ENTRIES=32768 > > > > and once kernel panics, at ddb prompts do: > > > show ktr > > > > I added the above options to my kernel, and performed a scripted textdump. > > /sbin/ddb script lockinfo="show locks; show alllocks; show lockedvnods" > /sbin/ddb script kdb.enter.panic="textdump set; capture on; show ktr ; > run lockinfo ; show pcpu; bt; ps; alltrace; capture off; call doadump; > reset" > > After the kernel paniced, the kdb.enter.panic script ran and created a > textdump. When I extracted the 2.7M ddb.txt file, it didn't show any > calls to lockmgr_disown in the ktr trace. > > Let me know if there is anything else that I can do. > > To get this dump, DB_CAPTURE_MAXBUFSIZE (sys/ddb/db_capture.c) needed > to be increased from its default of 512K to 5M, and then setting the > debug.ddb.capure.bufsize to 5M after rebooting with the new kernel. Scot, thanks a lot for your effort. I think I will produce more patch which can help for diagnosis very soon so that we can gather more informations and see what is the real culprit of this. > See PR 119993 (http://www.freebsd.org/cgi/query-pr.cgi?pr=119993) > which adds two new kernel options to allow the capture buffer size to > be changed at compile time. Oh, there is a PR bugathon too, this week... :) Attilio -- Peace can only be achieved by understanding - A. Einstein
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?3bbf2fe10801260509o12f7d5dof399a751ef48e5c7>