On Sun, May 25, 2025 at 09:32:09AM +0100, Al Viro wrote: > Breakage is still present in the current mainline ;-/ With CONFIG_DEBUG_VM on top of pagealloc debugging: [ 1434.992817] run fstests generic/127 at 2025-05-25 11:46:11g [ 1448.956242] BUG: Bad page state in process kworker/2:1 pfn:112cb0g [ 1448.956846] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x3e pfn:0x112cb0g [ 1448.957453] flags: 0x800000000000000e(referenced|uptodate|writeback|zone=2)g [ 1448.957863] raw: 800000000000000e dead000000000100 dead000000000122 0000000000000000g [ 1448.958303] raw: 000000000000003e 0000000000000000 00000000ffffffff 0000000000000000g [ 1448.958833] page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) setg [ 1448.959320] Modules linked in: xfs autofs4 fuse nfsd auth_rpcgss nfs_acl nfs lockd grace sunrpc loop ecryptfs 9pnet_virtio 9pnet netfs evdev pcspkr sg button ext4 jbd2 btrfs blake2b_generic xor zlib_deflate raid6_pq zstd_compress sr_mod cdrom ata_generic ata_piix psmouse serio_raw i2c_piix4 i2c_smbus libata e1000g [ 1448.960874] CPU: 2 UID: 0 PID: 2614 Comm: kworker/2:1 Not tainted 6.14.0-rc1+ #78g [ 1448.960878] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014g [ 1448.960879] Workqueue: xfs-conv/sdb1 xfs_end_io [xfs]g [ 1448.960938] Call Trace:g [ 1448.960939] <TASK>g [ 1448.960940] dump_stack_lvl+0x4f/0x60g [ 1448.960953] bad_page+0x6f/0x100g [ 1448.960957] free_frozen_pages+0x471/0x640g [ 1448.960958] iomap_finish_ioend+0x196/0x3c0g [ 1448.960963] iomap_finish_ioends+0x83/0xc0g [ 1448.960964] xfs_end_ioend+0x64/0x140 [xfs]g [ 1448.961003] xfs_end_io+0x93/0xc0 [xfs]g [ 1448.961036] process_one_work+0x153/0x390g [ 1448.961044] worker_thread+0x2ab/0x3b0g [ 1448.961045] ? rescuer_thread+0x470/0x470g [ 1448.961047] kthread+0xf7/0x200g [ 1448.961048] ? kthread_use_mm+0xa0/0xa0g [ 1448.961049] ret_from_fork+0x2d/0x50g [ 1448.961053] ? kthread_use_mm+0xa0/0xa0g [ 1448.961054] ret_from_fork_asm+0x11/0x20g [ 1448.961058] </TASK>g [ 1448.961155] Disabling lock debugging due to kernel taintg [ 1448.969569] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x3e pfn:0x112cb0g [ 1448.970023] flags: 0x800000000000000e(referenced|uptodate|writeback|zone=2)g [ 1448.970651] raw: 800000000000000e dead000000000100 dead000000000122 0000000000000000g [ 1448.971222] raw: 000000000000003e 0000000000000000 00000000ffffffff 0000000000000000g [ 1448.971812] page dumped because: VM_BUG_ON_FOLIO(((unsigned int) folio_ref_count(folio) + 127u <= 127u))g [ 1448.972490] ------------[ cut here ]------------g [ 1448.972841] kernel BUG at ./include/linux/mm.h:1455!g [ 1448.973421] Oops: invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOCg [ 1448.973853] CPU: 2 UID: 0 PID: 2614 Comm: kworker/2:1 Tainted: G B 6.14.0-rc1+ #78g [ 1448.974345] Tainted: [B]=BAD_PAGEg [ 1448.974565] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014g [ 1448.975074] Workqueue: xfs-conv/sdb1 xfs_end_io [xfs]g [ 1448.975428] RIP: 0010:folio_end_writeback+0x155/0x180g [ 1448.975731] Code: 13 40 0f 92 c5 e9 23 ff ff ff 48 c7 c6 00 d5 e7 81 48 89 df e8 0c 8a 03 00 0f 0b 48 c7 c6 d0 38 e5 81 48 89 df e8 fb 89 03 00 <0f> 0b 48 c7 c6 40 5b e5 81 48 89 df e8 ea 89 03 00 0f 0b 48 c7 c6g [ 1448.976655] RSP: 0018:ffffc90001a53d68 EFLAGS: 00010286g [ 1448.976953] RAX: 000000000000005c RBX: ffffea00044b2c00 RCX: 0000000000000000g [ 1448.977331] RDX: 0000000000000001 RSI: ffffffff81e74e9e RDI: 00000000ffffffffg [ 1448.977711] RBP: ffffea00044b2c40 R08: 0000000000004ffb R09: 00000000ffffefffg [ 1448.978089] R10: 00000000ffffefff R11: ffffffff82043bc0 R12: 0000000000001000g [ 1448.978464] R13: ffff888101ecb840 R14: 0000000000000000 R15: ffffea00044b2c00g [ 1448.978844] FS: 0000000000000000(0000) GS:ffff88842dd00000(0000) knlGS:0000000000000000g [ 1448.979289] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033g [ 1448.979609] CR2: 00007fd3d42a2000 CR3: 0000000111543000 CR4: 00000000000006f0g [ 1448.979989] Call Trace:g [ 1448.980170] <TASK>g [ 1448.980336] ? die+0x32/0x80g [ 1448.980543] ? do_trap+0xd5/0x100g [ 1448.980767] ? folio_end_writeback+0x155/0x180g [ 1448.981033] ? do_error_trap+0x65/0x80g [ 1448.981270] ? folio_end_writeback+0x155/0x180g [ 1448.981536] ? exc_invalid_op+0x4c/0x60g [ 1448.981790] ? folio_end_writeback+0x155/0x180g [ 1448.982056] ? asm_exc_invalid_op+0x16/0x20g [ 1448.982315] ? folio_end_writeback+0x155/0x180g [ 1448.982580] ? folio_end_writeback+0x155/0x180g [ 1448.982846] iomap_finish_ioend+0x196/0x3c0g [ 1448.983108] iomap_finish_ioends+0x55/0xc0g [ 1448.983363] xfs_end_ioend+0x64/0x140 [xfs]g [ 1448.983663] xfs_end_io+0x93/0xc0 [xfs]g [ 1448.983937] process_one_work+0x153/0x390g [ 1448.984189] worker_thread+0x2ab/0x3b0g [ 1448.984427] ? rescuer_thread+0x470/0x470g [ 1448.984674] kthread+0xf7/0x200g [ 1448.984887] ? kthread_use_mm+0xa0/0xa0g [ 1448.985128] ret_from_fork+0x2d/0x50g [ 1448.985362] ? kthread_use_mm+0xa0/0xa0g [ 1448.985601] ret_from_fork_asm+0x11/0x20g [ 1448.985846] </TASK>g [ 1448.986017] Modules linked in: xfs autofs4 fuse nfsd auth_rpcgss nfs_acl nfs lockd grace sunrpc loop ecryptfs 9pnet_virtio 9pnet netfs evdev pcspkr sg button ext4 jbd2 btrfs blake2b_generic xor zlib_deflate raid6_pq zstd_compress sr_mod cdrom ata_generic ata_piix psmouse serio_raw i2c_piix4 i2c_smbus libata e1000g [ 1448.987399] ---[ end trace 0000000000000000 ]---g [ 1448.987896] RIP: 0010:folio_end_writeback+0x155/0x180g [ 1448.988220] Code: 13 40 0f 92 c5 e9 23 ff ff ff 48 c7 c6 00 d5 e7 81 48 89 df e8 0c 8a 03 00 0f 0b 48 c7 c6 d0 38 e5 81 48 89 df e8 fb 89 03 00 <0f> 0b 48 c7 c6 40 5b e5 81 48 89 df e8 ea 89 03 00 0f 0b 48 c7 c6g [ 1448.989246] RSP: 0018:ffffc90001a53d68 EFLAGS: 00010286g [ 1448.992210] RAX: 000000000000005c RBX: ffffea00044b2c00 RCX: 0000000000000000g [ 1448.992619] RDX: 0000000000000001 RSI: ffffffff81e74e9e RDI: 00000000ffffffffg [ 1448.993010] RBP: ffffea00044b2c40 R08: 0000000000004ffb R09: 00000000ffffefffg [ 1448.993577] R10: 00000000ffffefff R11: ffffffff82043bc0 R12: 0000000000001000g [ 1448.994411] R13: ffff888101ecb840 R14: 0000000000000000 R15: ffffea00044b2c00g [ 1448.994823] FS: 0000000000000000(0000) GS:ffff88842dd00000(0000) knlGS:0000000000000000g [ 1448.995390] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033g [ 1448.995916] CR2: 00007fd3d42a2000 CR3: 0000000111543000 CR4: 00000000000006f0g kvm: terminating on signal 15 from pid 32057 (killall)
