Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753027Ab3IRQBO (ORCPT ); Wed, 18 Sep 2013 12:01:14 -0400 Received: from mail-ve0-f172.google.com ([209.85.128.172]:45759 "EHLO mail-ve0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751686Ab3IRQBM (ORCPT ); Wed, 18 Sep 2013 12:01:12 -0400 Message-ID: <5239CE42.3070105@gmail.com> Date: Wed, 18 Sep 2013 12:01:06 -0400 From: Dan Merillat User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130821 Icedove/17.0.8 MIME-Version: 1.0 To: Sasha Levin CC: Andrew Morton , "linux-mm@kvack.org" , LKML , walken@google.com, riel@redhat.com, hughd@google.com, khlebnikov@openvz.org, trinity@vger.kernel.org Subject: Re: mm: gpf in find_vma References: <522B9B5D.4010207@oracle.com> In-Reply-To: <522B9B5D.4010207@oracle.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 9026 Lines: 187 On 09/07/2013 05:32 PM, Sasha Levin wrote: > Hi all, > > While fuzzing with trinity inside a KVM tools guest, running latest > -next kernel, I've > stumbled on the following: > > The disassembly is: > > /* Check the cache first. */ > /* (Cache hit rate is typically around 35%.) */ > vma = ACCESS_ONCE(mm->mmap_cache); > 1f9: 48 8b 47 10 mov 0x10(%rdi),%rax > if (!(vma && vma->vm_end > addr && vma->vm_start <= addr)) { > 1fd: 48 85 c0 test %rax,%rax > 200: 74 0b je 20d > 202: 48 39 70 08 cmp %rsi,0x8(%rax) <--- here > 206: 76 05 jbe 20d > 208: 48 3b 30 cmp (%rax),%rsi > 20b: 73 4d jae 25a I may have hit the same thing earlier this morning: 191: 48 8b 47 08 mov 0x8(%rdi),%rax 195: 31 d2 xor %edx,%edx 197: 48 85 c0 test %rax,%rax 19a: 74 1c je 1b8 19c: 48 39 70 e8 cmp %rsi,-0x18(%rax) <-- here 1a0: 76 10 jbe 1b2 1a2: 48 39 70 e0 cmp %rsi,-0x20(%rax) 1a6: 48 8d 50 e0 lea -0x20(%rax),%rdx 1aa: 76 14 jbe 1c0 Except I got there via munmap(): Sep 18 04:58:04 kernel: [563331.669009] CPU: 0 PID: 3937 Comm: Xorg Not tainted 3.11.0-rc6-dan #1 Sep 18 04:58:04 kernel: [563331.669009] Hardware name: Gigabyte Technology Co., Ltd. GA-MA78GPM-DS2H/GA-MA78GPM-DS2H, BIOS F6h 12/25/2010 Sep 18 04:58:04 kernel: [563331.669009] task: ffff88021d8f9700 ti: ffff88021d66a000 task.ti: ffff88021d66a000 Sep 18 04:58:04 kernel: [563331.669009] RIP: 0010:[] [] find_vma+0x23/0x50 Sep 18 04:58:04 kernel: [563331.669009] RSP: 0018:ffff88021d66bed0 EFLAGS: 00010206 Sep 18 04:58:04 kernel: [563331.669009] RAX: 00ff8801e8e00ba0 RBX: ffff880212a3f0c0 RCX: 0000000000000000 Sep 18 04:58:04 kernel: [563331.669009] RDX: ffff8801ae075f18 RSI: 00007feef8258000 RDI: ffff880212a3f0c0 Sep 18 04:58:04 kernel: [563331.669009] RBP: ffff88021d66bed0 R08: 0000000000000000 R09: 00000000000000d1 Sep 18 04:58:04 kernel: [563331.669009] R10: 0000000000000000 R11: 0000000000000206 R12: ffff880212a3f0c0 Sep 18 04:58:04 kernel: [563331.669009] R13: 00007feef8258000 R14: 0000000000001000 R15: 00007feef8258000 Sep 18 04:58:04 kernel: [563331.669009] FS: 00007feefe54b880(0000) GS:ffff880227c00000(0000) knlGS:00000000f2640980 Sep 18 04:58:04 kernel: [563331.669009] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Sep 18 04:58:04 kernel: [563331.669009] CR2: 00007feef7486000 CR3: 00000002113d3000 CR4: 00000000000007f0 Sep 18 04:58:04 kernel: [563331.669009] Stack: Sep 18 04:58:04 kernel: [563331.669009] ffff88021d66bf20 ffffffff810eace0 ffff88021e23a420 ffff88021b411600 Sep 18 04:58:04 kernel: [563331.669009] 00007feef8258000 ffff880212a3f110 ffff880212a3f0c0 00007feef8258000 Sep 18 04:58:04 kernel: [563331.669009] 0000000000001000 000000000000002f ffff88021d66bf58 ffffffff810eaf1e Sep 18 04:58:04 kernel: [563331.669009] Call Trace: Sep 18 04:58:04 kernel: [563331.669009] [] do_munmap+0xdd/0x2de Sep 18 04:58:04 kernel: [563331.669009] [] vm_munmap+0x3d/0x56 Sep 18 04:58:04 kernel: [563331.669009] [] SyS_munmap+0x1e/0x24 Sep 18 04:58:04 kernel: [563331.669009] [] system_call_fastpath+0x1a/0x1f Sep 18 04:58:04 kernel: [563331.669009] Code: 85 c9 74 cb eb e4 5d c3 48 8b 47 10 55 48 89 e5 48 85 c0 74 0b 48 39 70 08 76 05 48 39 30 76 36 48 8b 47 08 31 d2 48 85 c0 74 1c <48> 39 70 e8 76 10 48 39 70 e0 48 8d 50 e0 76 14 48 8b 40 10 eb Sep 18 04:58:04 kernel: [563331.669009] RIP [] find_vma+0x23/0x50 Sep 18 04:58:04 kernel: [563331.669009] RSP Sep 18 04:58:04 kernel: [563331.690510] ---[ end trace 0b78e99bd4849eb8 ]--- This is possibly related, same machine, same path, same origin (Xorg, probably cookie clicker causing lots of allocation churn on both bugs) but an older kernel: Sep 11 13:17:33 kernel: [12808122.743464] general protection fault: 0000 [#3] PREEMPT SMP Sep 11 13:17:33 kernel: [12808122.746610] Modules linked in: uvcvideo videobuf2_vmalloc videobuf2_memops videobuf2_core videodev iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack ip_tables x_tables pl2303 usbserial nfnetlink_queue nfnetlink_log ntfs msdos reiserfs ext4 jbd2 ext3 jbd fuse arc4 ecb md4 sha256_generic nls_utf8 cifs fscache cdc_acm efivars nls_cp437 vfat fat sg usb_storage binfmt_misc rpcsec_gss_krb5 it87 hwmon_vid loop hid_generic snd_hda_codec_hdmi snd_hda_codec_realtek powernow_k8 kvm_amd kvm pcspkr k8temp snd_hda_intel snd_hda_codec snd_hwdep snd_pcm snd_page_alloc snd_seq snd_seq_device snd_timer i2c_piix4 rtc_cmos radeon snd drm_kms_helper ehci_pci ttm drm backlight i2c_algo_bit i2c_core wmi soundcore ide_pci_generic atiixp ide_core firewire_ohci firewire_core pata_acpi ohci_hcd ehci_hcd Sep 11 13:17:33 kernel: [12808122.751214] CPU 1 Sep 11 13:17:33 kernel: [12808122.751214] Pid: 5692, comm: Xorg Tainted: G D 3.9.0-rc7-dan #6 Gigabyte Technology Co., Ltd. GA-MA78GPM-DS2H/GA-MA78GPM-DS2H Sep 11 13:17:33 kernel: [12808122.751214] RIP: 0010:[] [] __rb_erase_color+0x148/0x215 Sep 11 13:17:33 kernel: [12808122.751214] RSP: 0018:ffff880208529e58 EFLAGS: 00010206 Sep 11 13:17:33 kernel: [12808122.751214] RAX: 00ff88021df483b8 RBX: ffff88015c87d248 RCX: ffff88015c87d450 Sep 11 13:17:33 kernel: [12808122.751214] RDX: 0000000000000000 RSI: ffff8802080f5048 RDI: ffff88015c87d248 Sep 11 13:17:33 kernel: [12808122.751214] RBP: ffff880208529e80 R08: ffff88015c87d238 R09: 0000000000003bd0 Sep 11 13:17:33 kernel: [12808122.751214] R10: 0000000000000000 R11: 0000000000003206 R12: ffff88015c87d978 Sep 11 13:17:33 kernel: [12808122.751214] R13: ffff88015c87d450 R14: ffff8802080f5048 R15: ffffffff810de579 Sep 11 13:17:33 kernel: [12808122.751214] FS: 00007f7041814880(0000) GS:ffff880227d00000(0000) knlGS:00000000f4285980 Sep 11 13:17:33 kernel: [12808122.751214] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Sep 11 13:17:33 kernel: [12808122.751214] CR2: 00007f703b2c0000 CR3: 000000014db58000 CR4: 00000000000007e0 Sep 11 13:17:33 kernel: [12808122.751214] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 Sep 11 13:17:33 kernel: [12808122.751214] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Sep 11 13:17:33 kernel: [12808122.751214] Process Xorg (pid: 5692, threadinfo ffff880208528000, task ffff880208079700) Sep 11 13:17:33 kernel: [12808122.751214] Stack: Sep 11 13:17:33 kernel: [12808122.751214] ffff88015c87d248 ffff88015c87d248 ffff88015c87d450 00007f703b5b4000 Sep 11 13:17:33 kernel: [12808122.751214] ffff88015c87d450 ffff880208529ec8 ffffffff810ded2f 0000000000000009 Sep 11 13:17:33 kernel: [12808122.751214] ffff8802080f5048 ffff8802080f5040 ffff88015c87d228 ffff88015c87d450 Sep 11 13:17:33 kernel: [12808122.751214] Call Trace: Sep 11 13:17:33 kernel: [12808122.751214] [] vma_rb_erase+0x1b5/0x1c2 Sep 11 13:17:33 kernel: [12808122.751214] [] do_munmap+0x1f0/0x31d Sep 11 13:17:33 kernel: [12808122.751214] [] vm_munmap+0x3d/0x56 Sep 11 13:17:33 kernel: [12808122.751214] [] sys_munmap+0x1e/0x24 Sep 11 13:17:33 kernel: [12808122.751214] [] system_call_fastpath+0x1a/0x1f Sep 11 13:17:33 kernel: [12808122.751214] Code: 48 39 58 10 75 06 4c 89 60 10 eb 09 4c 89 60 08 eb 03 4d 89 26 4c 89 e6 4d 89 ec 48 89 df 41 ff d7 49 8b 44 24 10 48 85 c0 74 05 00 01 74 66 4d 8b 6c 24 08 4d 85 ed 74 07 41 f6 45 00 01 74 Sep 11 13:17:33 kernel: [12808122.751214] RIP [] __rb_erase_color+0x148/0x215 Sep 11 13:17:33 kernel: [12808122.751214] RSP Sep 11 13:17:33 kernel: [12808122.920434] ---[ end trace 8913f036c5b4f342 ]--- Unfortunately I don't have the 3.9 build directory anymore, but here's a reconstruction: void __rb_erase_color(struct rb_node *parent, struct rb_root *root, void (*augment_rotate)(struct rb_node *old, struct rb_node *new)) ... /usr/src/3.9/lib/rbtree.c:322 if (!tmp1 || rb_is_black(tmp1)) { 13a: 48 85 c0 test %rax,%rax 13d: 74 05 je 144 <__rb_erase_color+0x144> 13f: f6 00 01 testb $0x1,(%rax) Both of mine look like current->mm is getting clobbered somewhere. -- 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/