Panic on boot after svn update

[Greg 'groggy' Lehey]

On Sunday, 29 July 2012 at  0:53:55 -0400, David J. Weller-Fahy wrote:
> So, I recently updated and encountered a panic on boot which is
> reproducible, and wanted to see if anyone's encountered this before I
> file a PR.  I found a problem in (I think) recent changes to the e1000
> driver.  I'm running FreeBSD 10-CURRENT as a VirtualBox guest.
>
> #v+
> FreeBSD fork-pooh 10.0-CURRENT FreeBSD 10.0-CURRENT #0 r238764: Sat Jul 28 17:21:47 EDT 2012     root at fork-pooh:/usr/obj/usr/src/sys/GENERIC  amd64
> #v-
>
> I have the Adapter Type set to, "Intel PRO/1000 MT Desktop (82540EM)", and the
> following card is detected by pciconf.
> ...
> Updating motd:.
> Starting ntpd.
> panic: _mtx_lock_sleep: recursed on non-recursive mutex em0 @ /usr/src/sys/dev/e1000/if_lem.c:881

<aol>Me too</aol> The panic message is identical, and I'm also running
in VirtualBox.  My version string (from strings on the kernel) is:

FreeBSD 10.0-CURRENT #4: Sat Jul 28 09:45:10 EST 2012
    root at swamp.lemis.com:/usr/obj/src/FreeBSD/svn/head/sys/GENERIC

Note that this is a different EST (UTC+10).

I have a dump, but I can't get much sense out of it:

kgdb: kvm_read: invalid address (0x354540a)
#0  0x00000000 in ?? ()

I'm currently rebuilding the system, but it looks as if that won't
help much.  One interesting point is that the first panic happened
after installing the new image (from yesterday's sources) while I was
trying to reboot with the old kernel, dating back to

FreeBSD swamp.lemis.com 10.0-CURRENT FreeBSD 10.0-CURRENT #3: Sun May 13 14:34:43 EST 2012     root at swamp.lemis.com:/usr/obj/src/FreeBSD/svn/head/sys/GENERIC  i386

Greg
--
Sent from my desktop computer.
Finger grog at FreeBSD.org for PGP public key.
See complete headers for address and phone numbers.
This message is digitally signed.  If your Microsoft MUA reports
problems, please read http://tinyurl.com/broken-mua
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 196 bytes
Desc: not available
Url : http://lists.freebsd.org/pipermail/freebsd-current/attachments/20120729/1603e786/attachment.pgp