From owner-freebsd-current@FreeBSD.ORG Sun Sep 8 23:36:14 2013 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTP id 1FCAAEB0; Sun, 8 Sep 2013 23:36:14 +0000 (UTC) (envelope-from davide.italiano@gmail.com) Received: from mail-vb0-x22a.google.com (mail-vb0-x22a.google.com [IPv6:2607:f8b0:400c:c02::22a]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id C11342742; Sun, 8 Sep 2013 23:36:13 +0000 (UTC) Received: by mail-vb0-f42.google.com with SMTP id e12so3522053vbg.15 for ; Sun, 08 Sep 2013 16:36:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:sender:in-reply-to:references:date:message-id:subject :from:to:cc:content-type; bh=JUYWZLQXtMZssXo6OdfnPdt8ft1VRlDO9LaZ5gGiqV4=; b=eQr02SMHuzOEMfmX1eOoDZVhbUpJ8cYAFTiZhXKiiZD5BEncqDAUK08zlFrWOWy0j6 jznBd4RF3feNi38GmixQ3MVSP0LASAXhw6Dd4T8DLpEJVIw3ekdLgCSWYLBcqCd3tqrD GKgvuUKQjMiomlx0Ck1NrWe1QpcN/PKKSGGj3o+KoY3tp7IUVBR2975+MlSwYzq8uBqm 4aIBigz3J/XGR84VmoJfR54tVDyYbqcPB2v3IkrriGoQiUjJs+J+q6k0QPCWbjVM/t6z lUEPts7WvOWPp//C5eeTAJE25KhaEZ/nxsvICRGLTEZraozSDQ2wBgzJsmvOgS+ZaMYY PU0A== MIME-Version: 1.0 X-Received: by 10.52.162.66 with SMTP id xy2mr11687553vdb.3.1378683372554; Sun, 08 Sep 2013 16:36:12 -0700 (PDT) Sender: davide.italiano@gmail.com Received: by 10.220.65.132 with HTTP; Sun, 8 Sep 2013 16:36:12 -0700 (PDT) In-Reply-To: <1378682844.60317.0.camel@localhost> References: <1378483253.1598.3.camel@localhost> <1378682844.60317.0.camel@localhost> Date: Sun, 8 Sep 2013 16:36:12 -0700 X-Google-Sender-Auth: 8CYhfSA6uwjS43iWEN_S8OLCWRo Message-ID: Subject: Re: Interesting panic from the Yahoo builder (10-current) From: Davide Italiano To: Sean Bruno Content-Type: text/plain; charset=ISO-8859-1 Cc: "freebsd-current@FreeBSD.org" X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 08 Sep 2013 23:36:14 -0000 On Sun, Sep 8, 2013 at 4:27 PM, Sean Bruno wrote: > On Sat, 2013-09-07 at 17:05 +0200, Davide Italiano wrote: >> On Fri, Sep 6, 2013 at 6:00 PM, Sean Bruno wrote: >> > Our "yBSD" builder needs to mount a disk image temporarily that has a >> > dos partition (for openstack-ish things) to put configs into it. It >> > seems that under high stress, we can squeeze a panic out of it in >> > namei(). >> > >> > Sean >> > >> > >> > Unread portion of the kernel message buffer: >> > panic: namei: nameiop contaminated with flags >> > cpuid = 8 >> > KDB: stack backtrace: >> > db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 0xfffffe048d8e53b0 >> > kdb_backtrace() at kdb_backtrace+0x39/frame 0xfffffe048d8e5460 >> > vpanic() at vpanic+0x126/frame 0xfffffe048d8e54a0 >> > kassert_panic() at kassert_panic+0x136/frame 0xfffffe048d8e5510 >> > namei() at namei+0x2c8/frame 0xfffffe048d8e5600 >> > msdosfs_mount() at msdosfs_mount+0x556/frame 0xfffffe048d8e57c0 >> > vfs_donmount() at vfs_donmount+0xc35/frame 0xfffffe048d8e5aa0 >> > sys_nmount() at sys_nmount+0x72/frame 0xfffffe048d8e5ae0 >> > amd64_syscall() at amd64_syscall+0x223/frame 0xfffffe048d8e5bf0 >> > Xfast_syscall() at Xfast_syscall+0xfb/frame 0xfffffe048d8e5bf0 >> > --- syscall (378, FreeBSD ELF64, sys_nmount), rip = 0x8000a8b68a, rsp = 0x7fffffffd508, rbp = 0x7fffffffdb30 --- >> > Uptime: 34m55s >> > Dumping 1140 out of 16350 MB:..2%..12%..22%..31%..41%..51%..61%..71%..82%..92% >> > >> > Reading symbols from /boot/modules/msdosfs.ko...done. >> > Loaded symbols for /boot/modules/msdosfs.ko >> > #0 doadump (textdump=1) at pcpu.h:227 >> > 227 pcpu.h: No such file or directory. >> > in pcpu.h >> > (kgdb) Hangup detected on fd 0 >> > error detected on stdin >> >> Can you please print the value of cnp->cn_nameiop (or, even better, >> the whole struct) before the panic? >> >> Thanks, >> > > Hrm ... tried to reproduce after recompiling the kernel (turning off > KDB_UNATTENDED) and its not happening now. > > I'll keep an eye out for it. > > Sean >From a first look (even without the informations) it looks very strange that the assertion fails, NDINIT() is called just before namei() in order to initialize struct nameidata, and that's what almost every other filesystem do, so I'm surprised noone hit this problem before. A (relatively random) guess is that you might run on (some sort of) broken hardware. Thanks, -- Davide "There are no solved problems; there are only problems that are more or less solved" -- Henri Poincare