From owner-freebsd-current@freebsd.org Thu Jul 5 17:48:23 2018 Return-Path: Delivered-To: freebsd-current@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 4AA8410420E8 for ; Thu, 5 Jul 2018 17:48:23 +0000 (UTC) (envelope-from pete@nomadlogic.org) Received: from vps-mail.nomadlogic.org (mail.nomadlogic.org [IPv6:2607:f2f8:a098::2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id D3F8E8C403; Thu, 5 Jul 2018 17:48:22 +0000 (UTC) (envelope-from pete@nomadlogic.org) Received: from [192.168.1.106] (cpe-75-82-194-8.socal.res.rr.com [75.82.194.8]) by vps-mail.nomadlogic.org (OpenSMTPD) with ESMTPSA id 16663894 TLS version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NO; Thu, 5 Jul 2018 10:48:20 -0700 (PDT) Subject: Re: atomic changes break drm-next-kmod? To: John Baldwin , Niclas Zeising , "O. Hartmann" , FreeBSD Current References: <20180703170223.266dbf5b@thor.intern.walstatt.dynvpn.de> <845aca10-8c01-fa3b-087f-f957df4e7531@nomadlogic.org> <063ae5c3-0584-1284-dd9d-ab8b5790baf1@FreeBSD.org> <0bf8e57b-fdb4-4c1a-3d0d-a734f8187ca8@nomadlogic.org> <4c5411dd-9f6b-7245-6ade-e11040f74687@FreeBSD.org> <24f5d737-a205-6fcc-0a33-a84601d2ff7a@nomadlogic.org> From: Pete Wright Message-ID: Date: Thu, 5 Jul 2018 10:48:16 -0700 User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:52.0) Gecko/20100101 Thunderbird/52.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.27 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: Thu, 05 Jul 2018 17:48:23 -0000 On 07/05/2018 10:10, John Baldwin wrote: > On 7/3/18 5:10 PM, Pete Wright wrote: >> >> On 07/03/2018 15:56, John Baldwin wrote: >>> On 7/3/18 3:34 PM, Pete Wright wrote: >>>> On 07/03/2018 15:29, John Baldwin wrote: >>>>> That seems like kgdb is looking at the wrong CPU. Can you use >>>>> 'info threads' and look for threads not stopped in 'sched_switch' >>>>> and get their backtraces? You could also just do 'thread apply >>>>> all bt' and put that file at a URL if that is easiest. >>>>> >>>> sure thing John - here's a gist of "thread apply all bt" >>>> >>>> https://gist.github.com/gem-pete/d8d7ab220dc8781f0827f965f09d43ed >>> That doesn't look right at all. Are you sure the kernel matches the >>> vmcore? Also, which kgdb version are you using? >>> >> yea i agree that doesn't look right at all.  here is my setup: >> >> $ which kgdb >> /usr/bin/kgdb >> $ kgdb >> GNU gdb 6.1.1 [FreeBSD] >> $ ls -lh /var/crash/vmcore.1 >> -rw-------  1 root  wheel   1.6G Jul  3 15:03 /var/crash/vmcore.1 >> $ ls -l /usr/lib/debug/boot/kernel/kernel.debug >> -r-xr-xr-x  1 root  wheel  87840496 Jul  3 13:54 >> /usr/lib/debug/boot/kernel/kernel.debug >> >> and i invoke kgdb like so: >> $ sudo kgdb /usr/lib/debug/boot/kernel/kernel.debug /var/crash/vmcore.1 >> >> here's a gist of my full gdb session: >> http://termbin.com/krsn >> >> dunno - maybe i have a bad core dump?  regardless, more than happy to >> help so let me know if i should try anything else or patches etc.. > Can you try installing gdb from ports and using /usr/local/bin/kgdb? > that seems to have done the trick, at least the output looks more encouraging.  --- trap 0, rip = 0, rsp = 0, rbp = 0 --- KDB: enter: panic __curthread () at ./machine/pcpu.h:231 231        __asm("movq %%gs:%1,%0" : "=r" (td) here's my full kgdb session: http://termbin.com/qa4f i don't see any threads not in "sched_switch" though :( -pete -- Pete Wright pete@nomadlogic.org @nomadlogicLA