Date: Tue, 31 May 2011 14:14:54 -0700 From: Garrett Cooper <yanegomi@gmail.com> To: mdf@freebsd.org Cc: svn-src-head@freebsd.org, svn-src-all@freebsd.org, src-committers@freebsd.org, "Kenneth D. Merry" <ken@freebsd.org> Subject: Re: svn commit: r222537 - in head/sys: kern sys Message-ID: <BANLkTinXpgPvG5U9V4o47HSXWc6J_ELR0w@mail.gmail.com> In-Reply-To: <BANLkTim1AQQj1BfqHtYfPWrvaQBp41qDNw@mail.gmail.com> References: <201105311729.p4VHTwrZ033296@svn.freebsd.org> <BANLkTim1AQQj1BfqHtYfPWrvaQBp41qDNw@mail.gmail.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On Tue, May 31, 2011 at 2:00 PM, <mdf@freebsd.org> wrote: > On Tue, May 31, 2011 at 10:29 AM, Kenneth D. Merry <ken@freebsd.org> wrot= e: >> Author: ken >> Date: Tue May 31 17:29:58 2011 >> New Revision: 222537 >> URL: http://svn.freebsd.org/changeset/base/222537 >> >> Log: >> =A0Fix apparent garbage in the message buffer. >> >> =A0While we have had a fix in place (options PRINTF_BUFR_SIZE=3D128) to = fix >> =A0scrambled console output, the message buffer and syslog were still ge= tting >> =A0log messages one character at a time. =A0While all of the characters = still >> =A0made it into the log (courtesy of atomic operations), they were often >> =A0interleaved when there were multiple threads writing to the buffer at= the >> =A0same time. > > This seems to panic my box with "lock "msgbuf" 0xfffffe0127ffffe0 > already initialized". > > Unfortunately, though I booted with a fresh CURRENT this morning > successfully, both /boot/kernel and /boot/kernel.old give this panic. > To add insult to injury, when the kernel drops into the debugger, my > keyboard input no longer works so I can't get a stack, etc. > > So: > > 1) Is there anything else I can do to help debug this? 1. sysctl debug.debugger_on_panic=3D1 ? > 2) how can I resurrect this box without a reinstall? 2. Best way is to probably to use the bsdinstall CD, use the LiveCD mode, setup the system as usual (mount /, mount devfs, chroot, mount -a), rewind to an earlier version of svn (shouldn't be too hard if you run /etc/rc.d/network restart from inside the chroot), rebuild the kernel (and potentially world), and install the kernel to the chroot, then exit and reboot (this is a method I picked up from installing Gentoo Linux multiple times, but it should work for FreeBSD as well). This is part of the reason why I'm an avid using of make installkernel INSTKERNNAME=3D$KERNCONF.$SVN_REVISION , symlink /boot/kernel to the latest one I want to boot, and I only go through every once in a blue moon to reap the kernels I don't need anymore -- I don't know until after a few weeks soak on my workstation whether or not a regression is present in the kernel. > I will try to repro on a virtual machine so I have a snapshot to come bac= k to. HTH! -Garrett
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?BANLkTinXpgPvG5U9V4o47HSXWc6J_ELR0w>