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Tue, 04 Mar 2025 21:33:33 -0800 (PST) Date: Tue, 04 Mar 2025 21:33:33 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <67c7e22d.050a0220.38b91b.024e.GAE@google.com> Subject: [syzbot] [mm?] WARNING in depot_fetch_stack From: syzbot To: akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspam-User: X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 025D7100006 X-Stat-Signature: jz99a37fijq6iqfciixe6ax69ucsj45i X-HE-Tag: 1741152814-73961 X-HE-Meta: U2FsdGVkX188ZH0ieptkd2Mrwv/BdoWSF/n14Zj7xwxGYG5n2BabBxBDi/D9K3PLQ1aWFFbhjO2fohFB+r8SVSVdKgsmfRn46CYByusevxY8PgIg2Pp3mM4GbBXm98+gjo18xF6SsiEGBTAwAnZvxHLcHK8pT/fsml8FKngjcNdo+SU9o4ddGwpSZe25LcDnJ9s+DEfdcgps0o+Wa4gfkzzibnDaqtVeJD3kFG8pRE2yXwoqPP69uEp24t+5Dx0IMEofgZ6gkrXLcf02D9l0n8hLOusAfy7Z2BnJn0WycJRemw//jUIClhVIGlAp6XGJ7orzZQufDjEWFZ1pDh7A0a9ACAHPVPwHF1sC86UtiIchdyi+cfy/mO1Wowj+wUL1+NhKxYaHCrkAAIAiW6eVgX4YOdv1orqkmFC79KbVQ4K/xVhNzO0ddNDgNHC8j/8L4SCzCAVzf7Vb3Wd49ZnQ2gXpK2dtU+MyN+3J9x6qvA4yJDQbPH6wiyaOw3yW+7xCCEfQ2+/WzUJTVNS/k9Dl8Bx1gWkg/DoNVExCAi+0d1x4qBsZzb26fhWsm5TgWP6uBnti4XyWUJWxCzeMYJ64nfDIJPxWpC9NwO5U1XT4hwo0Fg+ss6Gu2jPszoasdSbijaDBmBP5LmsCyq57SvvuqojCqgSPCoOzHy7dm2RmFLpUjkX9bMQ66nJc+14fN5aNsDMAeTLQaKbYJ5UdSwxfwKN4XTuW7Fn9HbilfgJ5wlYu11P1qQD5sTDG+kOQhj4nBBInXjIMq+VYKTX9OmKNNNuZRkta+ycSu4ZrWAqGYhiS6w+y3HH40CwxwY4s9kPH4v2UmNSPsjrwXdDcvrdlEkMSI7IdP4QIRoZsYfLLIQlsS7C2HZ2BCMG15qoUsXPBvAG6x+7JshvFePWYBQqy4JCvpyVm4lFiQSlSPIUzrHyCX6E6MzW8BE0rmZRQYyapERA2LwVX7qGRrwbLiRP MQZIIY4h 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 Sh/VsB3A AHYJn9gdXMr8CdEFViCU/qf0eFjUIqqiI5uqRMnmvRLw9S/B+WlmbQ13YhFNGaZpjztNAgPd1c7RU9hJADs1kbPjqy5ddoD+KiX9UGM4+2TwKS1qDdUY/S1rq5jTieD/rVgU8I3xjXNbjcujLp026Zr9vZxxzm+7lK50Ime8El8PWMo68u1jDL4cZTf83oDcSHA+m+5AAZz0QkVQgBAJJUyF6tDZxw+to0NzWQDfbYktZJ6hFlZjtLWLxLbXHqqIQnF+Pi4HklT0Ivt++diX0LZ9eqxu3UwW9ckXAfbi1Z2SG8tc7Vbe9IWbXSzyZlb7yEaVA0ni1dGiOLdWd4/vatH7VpUKQsRxzzUmU9xUZ0GWV93Zc/MUW20+dFsDc8dOgb6oOVFCXfeTfa3Uh6oi0dDlCMPIDBA0 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Hello, syzbot found the following issue on: HEAD commit: 276f98efb64a Merge tag 'block-6.14-20250228' of git://git..= . git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=3D17a6c864580000 kernel config: https://syzkaller.appspot.com/x/.config?x=3D5b4c41bdaeea196= 4 dashboard link: https://syzkaller.appspot.com/bug?extid=3D20024c0fe2bf6dbc8= c1e compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debia= n) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7fe= b34a89c2a/non_bootable_disk-276f98ef.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/5a036150d62e/vmlinux-= 276f98ef.xz kernel image: https://storage.googleapis.com/syzbot-assets/f0b6c8e5972f/bzI= mage-276f98ef.xz IMPORTANT: if you fix the issue, please add the following tag to the commit= : Reported-by: syzbot+20024c0fe2bf6dbc8c1e@syzkaller.appspotmail.com loop0: detected capacity change from 0 to 32768 bcachefs (loop0): starting version 1.7: mi_btree_bitmap opts=3Dmetadata_che= cksum=3Dnone,data_checksum=3Dnone,compression=3Dlz4,erasure_code,fsck,norec= overy,nojournal_transaction_names,reconstruct_alloc,nocow,no_data_io bcachefs (loop0): recovering from clean shutdown, journal seq 10 bcachefs (loop0): Version upgrade required: Version upgrade from 0.24: unwritten_extents to 1.7: mi_btree_bitmap incomp= lete Doing incompatible version upgrade from 0.24: unwritten_extents to 1.20: di= rectory_size running recovery passes: check_allocations,check_alloc_info,check_lrus,ch= eck_btree_backpointers,check_backpointers_to_extents,check_extents_to_backp= ointers,check_alloc_to_lru_refs,bucket_gens_init,check_snapshot_trees,check= _snapshots,check_subvols,check_subvol_children,delete_dead_snapshots,check_= inodes,check_extents,check_indirect_extents,check_dirents,check_xattrs,chec= k_root,check_unreachable_inodes,check_subvolume_structure,check_directory_s= tructure,check_nlinks,set_fs_needs_rebalance bcachefs (loop0): dropping and reconstructing all alloc info bcachefs (loop0): error validating btree node on loop0 at btree xattrs leve= l 0/0 u64s 11 type btree_ptr_v2 SPOS_MAX len 0 ver 0: seq 2285c34bed0abe32 writ= ten 16 min_key POS_MIN durability: 1 ptr: 0:31:0 gen 0 =20 node offset 0/16 bset u64s 60928: bset past end of btree node (offset 0 l= en 960 but written 16), exiting bcachefs (loop0): Unable to continue, halting bcachefs (loop0): flagging btree xattrs lost data bcachefs (loop0): running explicit recovery pass check_topology (2), curren= tly at recovery_pass_empty (0) bcachefs (loop0): running explicit recovery pass scan_for_btree_nodes (1), = currently at recovery_pass_empty (0) error reading btree root btree=3Dxattrs level=3D0: btree_node_read_error, f= ixing invalid bkey in btree_node btree=3Dsubvolumes level=3D0: u64s 7 type subvol= ume 0:1:0 len 0 ver 0: root 4096 snapshot id 0 invalid snapshot: delete?, fixing bcachefs (loop0): scan_for_btree_nodes... bcachefs (loop0): btree node scan found 7 nodes after overwrites done bcachefs (loop0): check_topology... bcachefs (loop0): btree root xattrs unreadable, must recover from scan bcachefs (loop0): bch2_get_scanned_nodes(): recovery btree=3Dxattrs level= =3D0 POS_MIN - SPOS_MAX bcachefs (loop0): bch2_get_scanned_nodes(): recovering u64s 11 type btree_p= tr_v2 SPOS_MAX len 0 ver 0: seq 2285c34bed0abe32 written 960 min_key POS_MI= N durability: 1 ptr: 0:31:0 gen 0 empty interior btree node at btree=3Dxattrs level=3D1 u64s 5 type btree_ptr SPOS_MAX len 0 ver 0, fixing bcachefs (loop0): empty btree root xattrs done bcachefs (loop0): accounting_read... done bcachefs (loop0): alloc_read... done bcachefs (loop0): stripes_read... done bcachefs (loop0): snapshots_read... done ------------[ cut here ]------------ WARNING: CPU: 0 PID: 5318 at lib/stackdepot.c:461 depot_fetch_stack+0x9c/0x= c0 lib/stackdepot.c:461 Modules linked in: CPU: 0 UID: 0 PID: 5318 Comm: syz.0.0 Not tainted 6.14.0-rc4-syzkaller-0021= 2-g276f98efb64a #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16= .3-2~bpo12+1 04/01/2014 RIP: 0010:depot_fetch_stack+0x9c/0xc0 lib/stackdepot.c:461 Code: 48 c7 c7 de fa 3a 8e 89 ee 44 89 f2 89 d9 e8 ab eb 53 fc 90 0f 0b 90 = 90 31 c0 5b 41 5e 5d c3 cc cc cc cc 90 0f 0b 90 eb ef 90 <0f> 0b 90 eb e9 4= 8 c7 c7 30 af 2b 8f 4c 89 f6 e8 50 67 00 00 eb 94 RSP: 0018:ffffc900019a71e0 EFLAGS: 00010246 RAX: ffff888044008000 RBX: 00000000000036b0 RCX: 0000000000100000 RDX: ffffc9000e64a000 RSI: ffffffff8c2ab700 RDI: ffffffff8c80f060 RBP: 000000000000025f R08: ffffffff82329a83 R09: 1ffffffff2079dee R10: dffffc0000000000 R11: fffffbfff2079def R12: 0000000000000001 R13: dffffc0000000000 R14: 000000000000025f R15: 0000000006d60260 FS: 00007f3e5c1916c0(0000) GS:ffff88801fc00000(0000) knlGS:000000000000000= 0 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555f8aa8e098 CR3: 000000003843c000 CR4: 0000000000352ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: dec_stack_record_count mm/page_owner.c:222 [inline] __reset_page_owner+0x320/0x430 mm/page_owner.c:310 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_frozen_pages+0xe0d/0x10e0 mm/page_alloc.c:2660 discard_slab mm/slub.c:2684 [inline] __put_partials+0x160/0x1c0 mm/slub.c:3153 put_cpu_partial+0x17c/0x250 mm/slub.c:3228 __slab_free+0x290/0x380 mm/slub.c:4479 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4115 [inline] slab_alloc_node mm/slub.c:4164 [inline] __do_kmalloc_node mm/slub.c:4293 [inline] __kmalloc_node_noprof+0x23c/0x4d0 mm/slub.c:4300 __kvmalloc_node_noprof+0x72/0x190 mm/util.c:662 __bch2_darray_resize_noprof+0xd2/0x290 fs/bcachefs/darray.c:24 bch2_write_super+0x48a/0x3cd0 fs/bcachefs/super-io.c:997 __bch2_check_set_feature+0xe6/0x150 fs/bcachefs/super-io.c:1180 bch2_check_set_feature fs/bcachefs/super-io.h:106 [inline] bch2_opt_check_may_set fs/bcachefs/opts.c:489 [inline] bch2_opts_check_may_set+0xf2/0x150 fs/bcachefs/opts.c:502 bch2_fs_start+0x3be/0x610 fs/bcachefs/super.c:1048 bch2_fs_get_tree+0xdb7/0x17a0 fs/bcachefs/fs.c:2203 vfs_get_tree+0x90/0x2b0 fs/super.c:1814 do_new_mount+0x2be/0xb40 fs/namespace.c:3560 do_mount fs/namespace.c:3900 [inline] __do_sys_mount fs/namespace.c:4111 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4088 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3e5b38e90a Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 = 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff f= f 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f3e5c190e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f3e5c190ef0 RCX: 00007f3e5b38e90a RDX: 00004000000058c0 RSI: 0000400000005900 RDI: 00007f3e5c190eb0 RBP: 00004000000058c0 R08: 00007f3e5c190ef0 R09: 0000000000010000 R10: 0000000000010000 R11: 0000000000000246 R12: 0000400000005900 R13: 00007f3e5c190eb0 R14: 0000000000005912 R15: 00004000000001c0 --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup