Date: Sat, 4 Oct 2014 03:51:39 +0100 From: "Steven Hartland" <killing@multiplay.co.uk> To: "Glen Barber" <gjb@FreeBSD.org>, <freebsd-stable@FreeBSD.org> Cc: FreeBSD Release Engineering Team <re@FreeBSD.org> Subject: Re: Heads-up: Possible regression between 10.0-RELEASE and 10.1-BETA1 with '/ on ZFS' setup Message-ID: <64F0D761D09546C7B47DFAA1551500BE@multiplay.co.uk> References: <20141004024011.GC1199@hub.FreeBSD.org>
next in thread | previous in thread | raw e-mail | index | archive | help
----- Original Message ----- From: "Glen Barber" <gjb@FreeBSD.org> > During testing of the 10.1-RC1, I set up a multi-disk VirtualBox VM to > test '/ on ZFS' in various scenarios. FreeBSD 10.1-RC1 i386, when > installed on ZFS with more than one disk (i.e., mirror, raidz-1, > raidz-2, etc.) crashes when rebooting post-install. > > This does not happen with a single-drive '/ on ZFS' setup under the same > configuration. > > FreeBSD 10.0-RELEASE i386 does not exhibit this behavior, however > upgrading from 10.0-RELEASE to 10.0-BETA1 or later may exhibit > a double-fault panic on boot. > > A possible solution to this is to set kern.kstack_pages=4 via loader(8), > however in my tests (solely in VirtualBox), this has been ineffective. > > It is unclear to me right now if this is something specific to > VirtualBox or not, though this problem was reported recently through > Bugzilla ( https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=194015 ). > > I am still bisecting the stable/10 tree to try to identify when this > possible regression was introduced, in addition to scrounging up the > hardware to be able to test this on a bare-metal machine to determine if > this is a VirtualBox (or hypervisor in general) specific problem, but > this is taking longer than initially expected. > > To be perfectly clear, the panic does occur in my particular testing > environment as far back as 10.1-BETA1, so this is *not* something new to > the upcoming 10.1-RC1. > > If you have a multi-drive '/ on ZFS' setup (mirror, raidz-1) *without* > PAE, and have upgraded to 10.1-BETA1 or later, please speak up in case > this is a problem specific to my testing environment, which will likely > be at least another day before I can verify is the case. This has been a known issue on i386 since the switch to Clang see UPDATING: 20121223: After switching to Clang as the default compiler some users of ZFS on i386 systems started to experience stack overflow kernel panics. Please consider using 'options KSTACK_PAGES=4' in such configurations. In my experience your millage may vary but essentially without 4 stack pages all bets are off in terms of stability. Regards Steve
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?64F0D761D09546C7B47DFAA1551500BE>