From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1BA68C4BA0B for ; Wed, 26 Feb 2020 11:12:29 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id BCEBA24689 for ; Wed, 26 Feb 2020 11:12:28 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BCEBA24689 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=bugzilla.kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 48SCnQ25j3zDqkJ for ; Wed, 26 Feb 2020 22:12:26 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=kernel.org (client-ip=198.145.29.99; helo=mail.kernel.org; envelope-from=srs0=+jiy=4o=bugzilla.kernel.org=bugzilla-daemon@kernel.org; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=bugzilla.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 48SChc6Fn4zDqR0 for ; Wed, 26 Feb 2020 22:08:16 +1100 (AEDT) From: bugzilla-daemon@bugzilla.kernel.org To: linuxppc-dev@lists.ozlabs.org Subject: [Bug 206669] Little-endian kernel crashing on POWER8 on heavy big-endian PowerKVM load Date: Wed, 26 Feb 2020 11:08:14 +0000 X-Bugzilla-Reason: None X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: AssignedTo platform_ppc-64@kernel-bugs.osdl.org X-Bugzilla-Product: Platform Specific/Hardware X-Bugzilla-Component: PPC-64 X-Bugzilla-Version: 2.5 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: npiggin@gmail.com X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P1 X-Bugzilla-Assigned-To: platform_ppc-64@kernel-bugs.osdl.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugzilla.kernel.org/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" https://bugzilla.kernel.org/show_bug.cgi?id=3D206669 --- Comment #5 from npiggin@gmail.com --- bugzilla-daemon@bugzilla.kernel.org's on February 26, 2020 8:28 pm: > https://bugzilla.kernel.org/show_bug.cgi?id=3D206669 >=20 > --- Comment #4 from John Paul Adrian Glaubitz (glaubitz@physik.fu-berlin.= de) > --- > (In reply to npiggin from comment #3) >> Do you have tracing / ftrace enabled in the host kernel for any >> reason? Turning that off might let the oops message get printed. >=20 > Seems that this is the case in the Debian kernel, yes: >=20 > root@watson:~# grep -i ftrace /boot/config-5.4.0-0.bpo.3-powerpc64le=20 > CONFIG_KPROBES_ON_FTRACE=3Dy > CONFIG_HAVE_KPROBES_ON_FTRACE=3Dy > CONFIG_HAVE_DYNAMIC_FTRACE=3Dy > CONFIG_HAVE_DYNAMIC_FTRACE_WITH_REGS=3Dy > CONFIG_HAVE_FTRACE_MCOUNT_RECORD=3Dy > CONFIG_FTRACE=3Dy > CONFIG_FTRACE_SYSCALLS=3Dy > CONFIG_DYNAMIC_FTRACE=3Dy > CONFIG_DYNAMIC_FTRACE_WITH_REGS=3Dy > CONFIG_FTRACE_MCOUNT_RECORD=3Dy > # CONFIG_FTRACE_STARTUP_TEST is not set > root@watson:~# >=20 > Do you have the kernel command option at hand which disables ftrace on the > command line? Is it just ftrace=3Doff? Hmm, not sure, Documentation/admin-guide/kernel-parameters.txt seems to say that wouldn't work. I thought it might only be going down that path if you have already done some tracing. Perhaps ensure /sys/kernel/debug/tracing/tracing_on is set to 0, and then `echo 1 > /sys/kernel/debug/tracing/free_buffer` before you start the test. >> > FWIW, the kernel image comes from this Debian package: >> >=20 >> >> >> >> >> >> >> >> http://snapshot.debian.org/archive/debian/20200211T210433Z/pool/main/l/l= inux/linux-image-5.4.0-0.bpo.3-powerpc64le_5.4.13-1%7Ebpo10%2B1_ppc64el.deb >>=20 >> Okay. Any chance you could test an upstream kernel?=20 >=20 > Sure, absolutely. Any preference on the version number? Current head if you're feeling lucky, but v5.5 if not. But you can give the ftrace test a try with the debian kernel first if you've got it ready to go. >> Don't bother testing that after the above -- panic_on_oops happens >> after oops_begin(), so it won't help unfortunately. >=20 > Okay. >=20 >> Attmepting to get into xmon might though, if you boot with xmon=3Don. >> Try that if tracing wasn't enabled, or disabling it doesn't help. >=20 > Okay. I will try to disable ftrace first, then retrigger the crash. Cool Thanks, Nick --=20 You are receiving this mail because: You are watching the assignee of the bug.=