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=-4.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,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 03517C433B4 for ; Tue, 18 May 2021 09:14:46 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (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 6F75061285 for ; Tue, 18 May 2021 09:14:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6F75061285 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=desiato.20200630; h=Sender:Content-Transfer-Encoding :Content-Type:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Subject:Cc:To: From:Message-ID:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=LxDSR8rxpMuxHvVGu3+NVazCI7UokQdJLsswOsu4njE=; b=AXExcs832xZFuuQhHe4yuLq7c 8eclU+xuQvUuCIVCP0DDHziM7Eu826tALH3gBNGPWnDkFPc0du+VCdUF0//t7AxWOOv9LlEw7zcHH 6o1+4gbbIfT00c1hlpuNhFcVdgmAWf3NXII2ZNOHRkKKsh/WuAaSuL8IQsqefWj/7DDI8BtgbqRa3 ucFLmgMR4zhF4yI83EYqxkPZlZpfVajsqXgx+tEN+201UA3bkX4xfKH//Rogk0+LWoivco+1A6Qbk q+XZZ3YwWm1YBYlBqADBeqmkHW6YpvuEJAx5x7WLH+oWnPNES2XJBpBhDLH88srWjKoMvwsJ5KcaH wdi0urzcQ==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1livmP-0004bZ-CF; Tue, 18 May 2021 09:12:45 +0000 Received: from bombadil.infradead.org ([2607:7c80:54:e::133]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1livmI-0004Zt-KJ for linux-arm-kernel@desiato.infradead.org; Tue, 18 May 2021 09:12:38 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Type:MIME-Version:References: In-Reply-To:Subject:Cc:To:From:Message-ID:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=Kxp/YzZYqXTvtzJ7ZpZtUsI1OIqOO+rQOMEIFdxdzDw=; b=usemoGvxBj12hEw0A5dcU3dNL8 Rl0hZ+kMRydWcJgSo0YNDdpOT5zhAUzUkL1mMaM73AtCuPo8aq4/6OEwa0gEUgDsTwCiZYSoBNBP7 juSdFb7GRwA9X8H487VBCKAvMT112pwfM/ZB+ycjZ5CjTQ6U+E+OJp6/TFF0dOWlSb1WrC5CwPC4+ mIMnLATwCSrsq/rRAXvTUY+MX4wkSZ5m7nNo4Z5VN+GryoHU9NFgZJdWnpCXZ7K+oyyHo+Xmn3Pql ncP2n1kTOZ9KJc4HCkAC27s/YY3KQRtbBoS7MmuMXi56Sm+15tfLgmkQ8vU3fZ72PB0Ow45DVBgT+ pn7Tboow==; Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1livmF-00EUsm-L2 for linux-arm-kernel@lists.infradead.org; Tue, 18 May 2021 09:12:37 +0000 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 042B861042; Tue, 18 May 2021 09:12:35 +0000 (UTC) Received: from 78.163-31-62.static.virginmediabusiness.co.uk ([62.31.163.78] helo=why.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1livmD-0021ws-50; Tue, 18 May 2021 10:12:33 +0100 Date: Tue, 18 May 2021 10:12:32 +0100 Message-ID: <878s4cv20v.wl-maz@kernel.org> From: Marc Zyngier To: John Stultz Cc: Catalin Marinas , Kees Cook , Will Deacon , Sami Tolvanen , linux-arm-kernel , Linux Kernel Mailing List , Bjorn Andersson , YongQin Liu , Amit Pundir , Michael Walle Subject: Re: REGRESSION: kernel BUG at arch/arm64/kernel/alternative.c:157! In-Reply-To: References: User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/27.1 (x86_64-pc-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") X-SA-Exim-Connect-IP: 62.31.163.78 X-SA-Exim-Rcpt-To: john.stultz@linaro.org, catalin.marinas@arm.com, keescook@chromium.org, will@kernel.org, samitolvanen@google.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, bjorn.andersson@linaro.org, yongqin.liu@linaro.org, amit.pundir@linaro.org, michael@walle.cc X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210518_021235_752591_DD1A0C52 X-CRM114-Status: GOOD ( 22.64 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org + Michael On Mon, 17 May 2021 22:52:59 +0100, John Stultz wrote: > > With v5.13-rc2, I've been seeing an odd boot regression with the > DragonBoard 845c: > > Unfortunately, trying to bisect it down (v5.13-rc1 works ok) is giving > me inconsistent results so far. It feels a bit like maybe some config > option gets enabled moving forward, and then sticks around when we go > back. I'll take another swing at bisecting it later today, but I have > to move on to some other work right now, so I figured I'd share (with > folks who better know the recent __apply_alternatives changes) in case > folks have a better idea: > > [ 0.254384] CPU features: detected: RAS Extension Support > [ 0.259928] CPU: All CPU(s) started at EL1 > [ 0.264127] alternatives: patching kernel code > [ 0.268635] ------------[ cut here ]------------ > [ 0.273303] kernel BUG at arch/arm64/kernel/alternative.c:157! > [ 0.279192] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP > [ 0.284736] Modules linked in: > [ 0.287833] CPU: 0 PID: 14 Comm: migration/0 Not tainted > 5.13.0-rc2-mainline #4501 > [ 0.295472] Hardware name: Thundercomm Dragonboard 845c (DT) > [ 0.301182] Stopper: multi_cpu_stop+0x0/0x1a0 <- > stop_machine_cpuslocked+0x128/0x160 > [ 0.309020] pstate: 204000c5 (nzCv daIF +PAN -UAO -TCO BTYPE=--) > [ 0.315086] pc : __apply_alternatives+0x1f0/0x270 > [ 0.319847] lr : __apply_alternatives+0xf4/0x270 > [ 0.324515] sp : ffffffc01020bca0 > [ 0.327874] x29: ffffffc01020bca0 x28: 00000000000000a0 x27: ffffffd7f5c11124 > [ 0.335086] x26: ffffffd7f5c11128 x25: 00000000001b0020 x24: ffffffd7f700ab90 > [ 0.342297] x23: 0000000000000000 x22: ffffffc01020bd20 x21: ffffffd7f7bea374 > [ 0.349508] x20: ffffffc01020bd30 x19: ffffffd7f72194fc x18: ffffffffffffffff > [ 0.356718] x17: ffffffd7f7bdce40 x16: 000000005c8e1b43 x15: ffffffd7f76d9d10 > [ 0.363929] x14: ffffffc09020b967 x13: ffffffc01020b975 x12: ffffffd7f76d9e30 > [ 0.371140] x11: 0000000005f5e0ff x10: ffffffc01020b8c0 x9 : 00000000ffffffd0 > [ 0.378350] x8 : 6b20676e69686374 x7 : ffffffd7f79b9238 x6 : c0000000ffff7fff > [ 0.385560] x5 : 0000000000000000 x4 : ffffffd7f5c22898 x3 : 0000000000000010 > [ 0.392771] x2 : 0000000000000004 x1 : 0000000000000000 x0 : 000000000000003f > [ 0.399982] Call trace: > [ 0.402461] __apply_alternatives+0x1f0/0x270 > [ 0.406873] __apply_alternatives_multi_stop+0xc0/0xe0 > [ 0.412062] multi_cpu_stop+0xb8/0x1a0 > [ 0.415851] cpu_stopper_thread+0xac/0x120 > [ 0.419997] smpboot_thread_fn+0x200/0x238 > [ 0.424146] kthread+0x14c/0x158 > [ 0.427423] ret_from_fork+0x10/0x1c > [ 0.431045] Code: 39402e61 39402a62 6b01005f 54fff500 (d4210000) > [ 0.437199] ---[ end trace 523e13d9d60a992d ]--- > [ 0.441868] note: migration/0[14] exited with preempt_count 2 > [ 0.447739] migration/0 (14) used greatest stack depth: 12448 bytes left [/me digs in my IRC logs] This looks a lot like an issue that was reported my Michael Walle a few days ago on IRC, leading to a crash that looked like this: [ 0.325238] alternatives: patching kernel code [ 0.329735] ------------[ cut here ]------------ [ 0.334394] kernel BUG at arch/arm64/kernel/alternative.c:157! [ 0.340300] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP [ 0.345836] Modules linked in: [ 0.348916] CPU: 0 PID: 14 Comm: migration/0 Not tainted 5.13.0-rc1-next-20210511+ #536 [ 0.356998] Hardware name: Kontron SMARC-sAL28 (Single PHY) on SMARC Eval 2.0 carrier (DT) [ 0.365339] Stopper: multi_cpu_stop+0x0/0x1a8 <- stop_cpus.constprop.9+0x78/0xc8 [ 0.372820] pstate: 200000c5 (nzCv daIF -PAN -UAO -TCO BTYPE=--) [ 0.378882] pc : __apply_alternatives.isra.1+0x1c4/0x270 [ 0.384246] lr : __apply_alternatives.isra.1+0x110/0x270 [ 0.389606] sp : ffff800012db3ca0 [ 0.392946] x29: ffff800012db3ca0 x28: 0000000000000000 x27: ffff800010011924 [ 0.400155] x26: ffff800010011928 x25: 00000000001b0020 x24: ffff8000115ad350 [ 0.407364] x23: ffff800012db3d28 x22: 0000000000000000 x21: ffff800011fb24cd [ 0.414571] x20: ffff800012db3d30 x19: ffff800011840b38 x18: 0000000000000010 [ 0.421779] x17: 0000000044a56c23 x16: 0000000000000002 x15: ffffffffffffffff [ 0.428986] x14: ffff800011d50a48 x13: ffff800092db3987 x12: ffff800011de6a70 [ 0.436193] x11: 0000000000000003 x10: ffff800011dcea30 x9 : ffff8000105d8928 [ 0.443401] x8 : 0000000000017fe8 x7 : c0000000ffffefff x6 : 0000000000000001 [ 0.450608] x5 : 0000000000000000 x4 : ffff800010024398 x3 : 0000000000000010 [ 0.457815] x2 : 0000000000000004 x1 : 0000000000000000 x0 : 000000000000003f [ 0.465022] Call trace: [ 0.467483] __apply_alternatives.isra.1+0x1c4/0x270 [ 0.472493] __apply_alternatives_multi_stop+0xcc/0xe0 [ 0.477679] multi_cpu_stop+0xac/0x1a8 [ 0.481460] cpu_stopper_thread+0xa4/0x138 [ 0.485592] smpboot_thread_fn+0x12c/0x268 [ 0.489725] kthread+0x164/0x168 [ 0.492980] ret_from_fork+0x10/0x30 [ 0.496588] Code: 39402e61 39402a62 6b01005f 54fff6a0 (d4210000) [ 0.502742] ---[ end trace 24ef7d65759ab825 ]--- [ 0.507398] note: migration/0[14] exited with preempt_count 2 [ 0.513290] ------------[ cut here ]------------ Michael subsequently reported that: mhh nevermind, I can't reproduce it anymore. Maybe I should have recompiled with a clean build dir at first My gut feeling is that we can end-up with some build leftovers when going between -rc1 and -rc2, hence the screw-up when the capabilities get reordered. Dependency issues? Thanks, M. -- Without deviation from the norm, progress is not possible. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel