Re: kern/37881: repeatable crash in filesystem when running MP

[Antti Kantee <pooka%cs.hut.fi@localhost>]

The following reply was made to PR kern/37881; it has been noted by GNATS.

From: Antti Kantee <pooka%cs.hut.fi@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: dieter.NetBSD%pandora.be@localhost
Subject: Re: kern/37881: repeatable crash in filesystem when running MP
Date: Sun, 27 Jan 2008 16:01:49 +0200

 Ok, the patch is unlikely to help.
 
 On Sun Jan 27 2008 at 13:50:03 +0000, dieter roelants wrote:
 >  >  > #25 0xc02c6727 in knote (list=0xcefe5be4, hint=6)
 >  >  >     at /usr/src/sys/kern/kern_event.c:1301
 >  >  
 >  >  print *list
 >  $1 = {slh_first = 0x0}
 
 Hmm, so you get kn from the list, but it's removed already before
 processing.
 
 >  >  print *kn
 >  $2 = {kn_link = {sle_next = 0xc304aea4}, kn_selnext = {sle_next = 0x0}, 
 >    kn_tqe = {tqe_next = 0xc055996c, tqe_prev = 0x0}, kn_kq = 0x0, kn_kevent 
 > = {
 >      ident = 0, filter = 1048576, flags = 1, fflags = 4096, data = 4096, 
 >      udata = -842719232}, kn_status = 3487384, kn_sfflags = 0, 
 >    kn_sdata = 3487447, kn_ptr = {p_fp = 0x0, p_proc = 0x0, p_opaque = 0x0}, 
 >    kn_fop = 0x0, kn_hook = 0x0}
 
 And kn_fop is NULL causing the panic.
 
 Hmm.  Can you see what the other CPU was doing?  Maybe nautilus is evil
 enough to close the fd in another thread while the write is in progress
 or something like that.
 
 -- 
 Antti Kantee <pooka%iki.fi@localhost>                     Of course he runs 
NetBSD
 http://www.iki.fi/pooka/                          http://www.NetBSD.org/
     "la qualité la plus indispensable du cuisinier est l'exactitude"