From: Jan Kara Subject: Re: [BUG] softlockup observed with 64k block size on ppc64 Date: Tue, 25 Oct 2016 10:13:19 +0200 Message-ID: <20161025081319.GC16260@quack2.suse.cz> References: <369354227.RU6GsvOxus@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-ext4@vger.kernel.org, tytso@mit.edu, jack@suse.cz To: Chandan Rajendra Return-path: Received: from mx2.suse.de ([195.135.220.15]:59733 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753302AbcJYINV (ORCPT ); Tue, 25 Oct 2016 04:13:21 -0400 Content-Disposition: inline In-Reply-To: <369354227.RU6GsvOxus@localhost.localdomain> Sender: linux-ext4-owner@vger.kernel.org List-ID: Hi! On Mon 24-10-16 14:10:02, Chandan Rajendra wrote: > The following soft lockup occurs when fstests' ext4/303 test is executed with > 64k block size on a ppc64 machine running linux-4.8 kernel. Thanks for report! I had a look into the code and I'm not sure why this happens. Is this reproducible? Did it happen also with older kernels? Honza > > NMI watchdog: BUG: soft lockup - CPU#1 stuck for 23s! [fio:12268] > Modules linked in: > CPU: 1 PID: 12268 Comm: fio Not tainted 4.8.0 #1 > task: c00000062d344900 task.stack: c0000006283c4000 > NIP: c0000000003a55e4 LR: c0000000003a5564 CTR: 0000000000000000 > REGS: c0000006283c6fb0 TRAP: 0901 Not tainted (4.8.0) > MSR: 8000000002009032 CR: 44428848 XER: 00000000 > CFAR: c0000000003a5670 SOFTE: 1 > GPR00: c0000000003a79cc c0000006283c7230 c00000000110f100 0000000000008010 > GPR04: 0000000000000000 c000000630fd7000 fffffffffffffffe 0000000000000010 > GPR08: 0000000000008010 ffffffffffffffff 000000000000000f 0000000081860c2d > GPR12: 0000000024428244 c00000000fe00400 > NIP [c0000000003a55e4] .ext4_mb_generate_buddy+0x1a4/0x450 > LR [c0000000003a5564] .ext4_mb_generate_buddy+0x124/0x450 > Call Trace: > [c0000006283c7230] [0000000000000002] 0x2 (unreliable) > [c0000006283c7340] [c0000000003a79cc] .ext4_mb_init_cache+0x43c/0x830 > [c0000006283c7470] [c0000000003a8040] .ext4_mb_init_group+0x280/0x350 > [c0000006283c7540] [c0000000003a8340] .ext4_mb_good_group+0x230/0x240 > [c0000006283c75e0] [c0000000003abf8c] .ext4_mb_regular_allocator+0x2ec/0x540 > [c0000006283c7720] [c0000000003ae1c0] .ext4_mb_new_blocks+0x680/0xd80 > [c0000006283c7820] [c00000000039ee98] .ext4_ext_map_blocks+0x758/0x1d20 > [c0000006283c79d0] [c000000000365e24] .ext4_map_blocks+0x1c4/0x750 > [c0000006283c7ab0] [c000000000399230] .ext4_alloc_file_blocks.isra.6+0x170/0x3e0 > [c0000006283c7be0] [c0000000003a1e24] .ext4_fallocate+0x2f4/0xa20 > [c0000006283c7cf0] [c000000000283f54] .vfs_fallocate+0x144/0x290 > [c0000006283c7d90] [c000000000285298] .SyS_fallocate+0x58/0xd0 > [c0000006283c7e30] [c000000000009560] system_call+0x38/0x108 > Instruction dump: > 889e0014 7f042030 5484043e 7e892378 7d2907b4 7d4900d0 7d494838 7d070034 > 7d290074 2147001f 2129003f 7f895000 <409d0008> 7d495378 7d2a07b4 2e890000 > > -- > chandan > -- Jan Kara SUSE Labs, CR