Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935154AbaDJKZp (ORCPT ); Thu, 10 Apr 2014 06:25:45 -0400 Received: from mta-out.inet.fi ([195.156.147.13]:46968 "EHLO kirsi1.inet.fi" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933885AbaDJKZn (ORCPT ); Thu, 10 Apr 2014 06:25:43 -0400 Date: Thu, 10 Apr 2014 13:25:27 +0300 From: "Kirill A. Shutemov" To: Michel Lespinasse Cc: Sasha Levin , Andrew Morton , Andrea Arcangeli , Dave Jones , "linux-mm@kvack.org" , LKML , "Kirill A. Shutemov" , Vlastimil Babka Subject: Re: mm: kernel BUG at mm/huge_memory.c:1829! Message-ID: <20140410102527.GA24111@node.dhcp.inet.fi> References: <53440991.9090001@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <53440991.9090001@oracle.com> User-Agent: Mutt/1.5.22.1-rc1 (2013-10-16) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 08, 2014 at 10:37:05AM -0400, Sasha Levin wrote: > Hi all, > > While fuzzing with trinity inside a KVM tools guest running the latest -next > kernel, I've stumbled on the following: > > [ 1275.253114] kernel BUG at mm/huge_memory.c:1829! > [ 1275.253642] invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC > [ 1275.254775] Dumping ftrace buffer: > [ 1275.255631] (ftrace buffer empty) > [ 1275.256440] Modules linked in: > [ 1275.257347] CPU: 20 PID: 22807 Comm: trinity-c299 Not tainted 3.14.0-next-20140407-sasha-00023-gd35b0d6 #382 > [ 1275.258686] task: ffff8803e7873000 ti: ffff8803e7896000 task.ti: ffff8803e7896000 > [ 1275.259416] RIP: __split_huge_page (mm/huge_memory.c:1829 (discriminator 1)) > [ 1275.260527] RSP: 0018:ffff8803e7897bb8 EFLAGS: 00010297 > [ 1275.261323] RAX: 000000000000012c RBX: ffff8803e789d600 RCX: 0000000000000006 > [ 1275.261323] RDX: 0000000000005b80 RSI: ffff8803e7873d00 RDI: 0000000000000282 > [ 1275.261323] RBP: ffff8803e7897c68 R08: 0000000000000000 R09: 0000000000000000 > [ 1275.261323] R10: 0000000000000001 R11: 30303320746e756f R12: 0000000000000000 > [ 1275.261323] R13: 0000000000a00000 R14: ffff8803ede73000 R15: ffffea0010030000 > [ 1275.261323] FS: 00007f899d23f700(0000) GS:ffff880437000000(0000) knlGS:0000000000000000 > [ 1275.261323] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b > [ 1275.261323] CR2: 00000000024cf048 CR3: 00000003e787f000 CR4: 00000000000006a0 > [ 1275.261323] DR0: 0000000000696000 DR1: 0000000000696000 DR2: 0000000000000000 > [ 1275.261323] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 > [ 1275.261323] Stack: > [ 1275.261323] ffff8803e7897bd8 ffff880024dab898 ffff8803e7897bd8 ffffffffac1bea0e > [ 1275.261323] ffff8803e7897c28 0000000000000282 00000014b06cc072 0000000000000000 > [ 1275.261323] 0000012be7897c28 0000000000000a00 ffff880024dab8d0 ffff880024dab898 > [ 1275.261323] Call Trace: > [ 1275.261323] ? put_lock_stats.isra.12 (arch/x86/include/asm/preempt.h:98 kernel/locking/lockdep.c:254) > [ 1275.261323] ? down_write (kernel/locking/rwsem.c:51 (discriminator 2)) > [ 1275.261323] ? split_huge_page_to_list (mm/huge_memory.c:1874) > [ 1275.261323] split_huge_page_to_list (include/linux/vmstat.h:37 mm/huge_memory.c:1879) > [ 1275.261323] __split_huge_page_pmd (mm/huge_memory.c:2811) > [ 1275.261323] ? mutex_unlock (kernel/locking/mutex.c:220) > [ 1275.261323] ? __mutex_unlock_slowpath (arch/x86/include/asm/paravirt.h:809 kernel/locking/mutex.c:713 kernel/locking/mutex.c:722) > [ 1275.261323] ? get_parent_ip (kernel/sched/core.c:2471) > [ 1275.261323] ? preempt_count_sub (kernel/sched/core.c:2526) > [ 1275.261323] follow_page_mask (mm/memory.c:1518 (discriminator 1)) > [ 1275.261323] SYSC_move_pages (mm/migrate.c:1227 mm/migrate.c:1353 mm/migrate.c:1508) > [ 1275.261323] ? SYSC_move_pages (include/linux/rcupdate.h:800 mm/migrate.c:1472) > [ 1275.261323] ? sched_clock_local (kernel/sched/clock.c:213) > [ 1275.261323] SyS_move_pages (mm/migrate.c:1456) > [ 1275.261323] tracesys (arch/x86/kernel/entry_64.S:749) > [ 1275.261323] Code: c0 01 39 45 94 74 18 41 8b 57 18 48 c7 c7 90 5e 6d b0 31 c0 8b 75 94 83 c2 01 e8 3d 6a 23 03 41 8b 47 18 83 c0 01 39 45 94 74 02 <0f> 0b 49 8b 07 48 89 c2 48 c1 e8 34 83 e0 03 48 c1 ea 36 4c 8d > [ 1275.261323] RIP __split_huge_page (mm/huge_memory.c:1829 (discriminator 1)) > [ 1275.261323] RSP > > Looking at the code, there was supposed to be a printk printing both > mapcounts if they're different. However, there was no matching entry > in the log for that. We had the bug triggered a year ago[1] and I tried to ask whether it can caused by chaining the same_anon_vma list with interval tree[2]. It's not obvious for me how new implementation of anon rmap with interval tree guarantee behaviour of anon_vma_interval_tree_foreach() vs. anon_vma_interval_tree_insert() which __split_huge_page() expects. Michel, could you clarify that? [1] https://bugzilla.redhat.com/show_bug.cgi?id=923817 [2] http://article.gmane.org/gmane.linux.kernel.mm/96518 -- Kirill A. Shutemov -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/