Date: Wed, 7 Dec 2005 09:27:12 -0500 From: John Baldwin <jhb@freebsd.org> To: Yuri Khotyaintsev <yuri@irfu.se> Cc: freebsd-hackers@freebsd.org, freebsd-stable@freebsd.org Subject: Re: Fatal trap 12: page fault while in kernel mode Message-ID: <200512070927.14391.jhb@freebsd.org> In-Reply-To: <200512070847.04980.yuri@irfu.se> References: <200512021100.03167.yuri@irfu.se> <200512020854.20959.jhb@freebsd.org> <200512070847.04980.yuri@irfu.se>
next in thread | previous in thread | raw e-mail | index | archive | help
On Wednesday 07 December 2005 02:47 am, Yuri Khotyaintsev wrote: > On Friday 02 December 2005 14.54, John Baldwin wrote: > > On Friday 02 December 2005 05:00 am, Yuri Khotyaintsev wrote: > > > I have the following panic occurring several times a week. The machine > > > is an NFS server, and it usually panics early in the morning, when > > > first people try to access it. After reboot it may work OK for 1-2 > > > days, and then panics again. I have tried changing memory and replaci= ng > > > disk which was exported via NFS, but nothing helped :( > > > > > > Any suggestion on how to fix this panic will be very much appreciated= ! > > > > This panic (in propagate_priority) is usually caused when a thread goes > > to sleep while holding a mutex (which is forbidden). If you enable > > INVARIANTS and/or WITNESS you should get a better panic, and with WITNE= SS > > you will even be warned when a thread goes to sleep while holding a > > mutex. However, these options do introduce considerable execution > > overhead, and sometimes that overhead changes the timing enough to hide > > the race. :( > > Here are the two panics which I got with INVARIANTS and WITNESS enabled. > > Unread portion of the kernel message buffer: > Memory modified after free 0xc4759e00(508) val=3D0 @ 0xc4759e00 > panic: Most recently used by UFS dirhash Well, this isn't the panic I was expecting, but it points to something=20 trashing free'd memory via a stale pointer or some such. You might be able= =20 to use MEMGUARD to track this down. =2D-=20 John Baldwin <jhb@FreeBSD.org> =A0<>< =A0http://www.FreeBSD.org/~jhb/ "Power Users Use the Power to Serve" =A0=3D =A0http://www.FreeBSD.org
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200512070927.14391.jhb>