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=-2.4 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=unavailable 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 762CAC65BB3 for ; Mon, 10 Dec 2018 13:53:23 +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 C6C0221479 for ; Mon, 10 Dec 2018 13:53:22 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C6C0221479 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com 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 43D4KX5Qv3zDqjJ for ; Tue, 11 Dec 2018 00:53:20 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=arm.com (client-ip=217.140.101.70; helo=foss.arm.com; envelope-from=catalin.marinas@arm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=arm.com Received: from foss.arm.com (foss.arm.com [217.140.101.70]) by lists.ozlabs.org (Postfix) with ESMTP id 43D4Gf3mlVzDqfb for ; Tue, 11 Dec 2018 00:50:49 +1100 (AEDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id B336E1596; Mon, 10 Dec 2018 05:50:47 -0800 (PST) Received: from arrakis.emea.arm.com (arrakis.cambridge.arm.com [10.1.196.113]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 2AE5F3F575; Mon, 10 Dec 2018 05:50:42 -0800 (PST) Date: Mon, 10 Dec 2018 13:50:39 +0000 From: Catalin Marinas To: Doug Anderson Subject: Re: [REPOST PATCH v6 0/4] kgdb: Fix kgdb_roundup_cpus() Message-ID: <20181210135038.GC4048@arrakis.emea.arm.com> References: <20181205033828.6156-1-dianders@chromium.org> <20181207174231.GD11961@arrakis.emea.arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) 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: , Cc: mhocko@suse.com, linux-sh@vger.kernel.org, Peter Zijlstra , Will Deacon , linux-mips@vger.kernel.org, dalias@libc.org, paulus@samba.org, "H. Peter Anvin" , sparclinux@vger.kernel.org, Daniel Thompson , Yoshinori Sato , x86@kernel.org, Russell King - ARM Linux , Ingo Molnar , ying.huang@intel.com, jhogan@kernel.org, linux-snps-arc@lists.infradead.org, Jason Wessel , rppt@linux.vnet.ibm.com, bp@alien8.de, Thomas Gleixner , Linux ARM , Vineet Gupta , LKML , Ralf Baechle , rkuo@codeaurora.org, paul.burton@mips.com, linux-hexagon@vger.kernel.org, kgdb-bugreport@lists.sourceforge.net, Andrew Morton , linuxppc-dev , David Miller Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Hi Doug, On Fri, Dec 07, 2018 at 10:40:24AM -0800, Doug Anderson wrote: > On Fri, Dec 7, 2018 at 9:42 AM Catalin Marinas wrote: > > On Tue, Dec 04, 2018 at 07:38:24PM -0800, Douglas Anderson wrote: > > > Douglas Anderson (4): > > > kgdb: Remove irq flags from roundup > > > kgdb: Fix kgdb_roundup_cpus() for arches who used smp_call_function() > > > kgdb: Don't round up a CPU that failed rounding up before > > > kdb: Don't back trace on a cpu that didn't round up > > > > FWIW, trying these on arm64 (ThunderX2) with CONFIG_KGDB_TESTS_ON_BOOT=y > > on top of 4.20-rc5 doesn't boot. It looks like they leave interrupts > > disabled when they shouldn't and it trips over the BUG at > > mm/vmalloc.c:1380 (called via do_fork -> copy_process). > > > > Now, I don't think these patches make things worse on arm64 since prior > > to them the kgdb boot tests on arm64 were stuck in a loop (RUN > > singlestep). > > Thanks for the report! ...actually, I'd never tried CONFIG_KGDB_TESTS > before. ...so I tried them now: > > A) chromeos-4.19 tree on qcom-sdm845 without this series: booted up OK > B) chromeos-4.19 tree on qcom-sdm845 with this series: booted up OK > C) v4.20-rc5-90-g30002dd008ed on rockchip-rk3399 (kevin) with this > series: booted up OK > > Example output from B) above: > > localhost ~ # dmesg | grep kgdbts > [ 2.139814] KGDB: Registered I/O driver kgdbts > [ 2.144582] kgdbts:RUN plant and detach test > [ 2.165333] kgdbts:RUN sw breakpoint test > [ 2.172990] kgdbts:RUN bad memory access test > [ 2.178640] kgdbts:RUN singlestep test 1000 iterations > [ 2.187765] kgdbts:RUN singlestep [0/1000] > [ 2.559596] kgdbts:RUN singlestep [100/1000] > [ 2.931419] kgdbts:RUN singlestep [200/1000] > [ 3.303474] kgdbts:RUN singlestep [300/1000] > [ 3.675121] kgdbts:RUN singlestep [400/1000] > [ 4.046867] kgdbts:RUN singlestep [500/1000] > [ 4.418920] kgdbts:RUN singlestep [600/1000] > [ 4.790824] kgdbts:RUN singlestep [700/1000] > [ 5.162479] kgdbts:RUN singlestep [800/1000] > [ 5.534103] kgdbts:RUN singlestep [900/1000] > [ 5.902299] kgdbts:RUN do_fork for 100 breakpoints > [ 8.463900] KGDB: Unregistered I/O driver kgdbts, debugger disabled > > ...so I guess I'm a little confused. Either I have a different config > than you do or something is special about your machine? I tried it now on a Juno board both as a host and a guest and boots fine. It must be something that only triggers ThunderX2. Ignore the report for now, if I find anything interesting I'll let you know. -- Catalin