====================================================== WARNING: possible circular locking dependency detected 6.13.0-rc7-syzkaller-00149-g9bffa1ad25b8 #0 Not tainted ------------------------------------------------------ syz.3.19/5622 is trying to acquire lock: ffffe8ffffc37f50 (&per_cpu_ptr(pool->acomp_ctx, cpu)->mutex){+.+.}-{4:4}, at: acomp_ctx_get_cpu_lock mm/zswap.c:899 [inline] ffffe8ffffc37f50 (&per_cpu_ptr(pool->acomp_ctx, cpu)->mutex){+.+.}-{4:4}, at: zswap_compress mm/zswap.c:931 [inline] ffffe8ffffc37f50 (&per_cpu_ptr(pool->acomp_ctx, cpu)->mutex){+.+.}-{4:4}, at: zswap_store_page mm/zswap.c:1456 [inline] ffffe8ffffc37f50 (&per_cpu_ptr(pool->acomp_ctx, cpu)->mutex){+.+.}-{4:4}, at: zswap_store+0xa3b/0x1c30 mm/zswap.c:1563 but task is already holding lock: ffffffff8ea36f00 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:3926 [inline] ffffffff8ea36f00 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim+0xd4/0x3c0 mm/page_alloc.c:3951 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (fs_reclaim){+.+.}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __fs_reclaim_acquire mm/page_alloc.c:3853 [inline] fs_reclaim_acquire+0x88/0x130 mm/page_alloc.c:3867 might_alloc include/linux/sched/mm.h:318 [inline] slab_pre_alloc_hook mm/slub.c:4070 [inline] slab_alloc_node mm/slub.c:4148 [inline] __kmalloc_cache_node_noprof+0x40/0x3a0 mm/slub.c:4337 kmalloc_node_noprof include/linux/slab.h:924 [inline] zswap_cpu_comp_prepare+0xdc/0x400 mm/zswap.c:828 cpuhp_invoke_callback+0x415/0x830 kernel/cpu.c:204 cpuhp_issue_call+0x46f/0x7e0 __cpuhp_state_add_instance_cpuslocked+0x1ed/0x500 kernel/cpu.c:2437 __cpuhp_state_add_instance+0x27/0x40 kernel/cpu.c:2458 cpuhp_state_add_instance include/linux/cpuhotplug.h:386 [inline] zswap_pool_create+0x38c/0x680 mm/zswap.c:291 zswap_setup+0x32a/0x4b0 mm/zswap.c:1811 do_one_initcall+0x248/0x870 init/main.c:1266 do_initcall_level+0x157/0x210 init/main.c:1328 do_initcalls+0x3f/0x80 init/main.c:1344 kernel_init_freeable+0x435/0x5d0 init/main.c:1577 kernel_init+0x1d/0x2b0 init/main.c:1466 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 -> #0 (&per_cpu_ptr(pool->acomp_ctx, cpu)->mutex){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 acomp_ctx_get_cpu_lock mm/zswap.c:899 [inline] zswap_compress mm/zswap.c:931 [inline] zswap_store_page mm/zswap.c:1456 [inline] zswap_store+0xa3b/0x1c30 mm/zswap.c:1563 swap_writepage+0x647/0xce0 mm/page_io.c:279 shmem_writepage+0x1248/0x1610 mm/shmem.c:1579 pageout mm/vmscan.c:696 [inline] shrink_folio_list+0x3b68/0x5ca0 mm/vmscan.c:1374 evict_folios+0x3c92/0x58c0 mm/vmscan.c:4600 try_to_shrink_lruvec+0x9a6/0xc70 mm/vmscan.c:4799 shrink_one+0x3b9/0x850 mm/vmscan.c:4844 shrink_many mm/vmscan.c:4907 [inline] lru_gen_shrink_node mm/vmscan.c:4985 [inline] shrink_node+0x37c5/0x3e50 mm/vmscan.c:5966 shrink_zones mm/vmscan.c:6225 [inline] do_try_to_free_pages+0x78c/0x1cf0 mm/vmscan.c:6287 try_to_free_pages+0x47c/0x1050 mm/vmscan.c:6537 __perform_reclaim mm/page_alloc.c:3929 [inline] __alloc_pages_direct_reclaim+0x178/0x3c0 mm/page_alloc.c:3951 __alloc_pages_slowpath+0x764/0x1020 mm/page_alloc.c:4382 __alloc_pages_noprof+0x49b/0x710 mm/page_alloc.c:4766 alloc_pages_mpol_noprof+0x3e1/0x780 mm/mempolicy.c:2269 folio_alloc_mpol_noprof+0x36/0x50 mm/mempolicy.c:2288 shmem_alloc_folio mm/shmem.c:1799 [inline] shmem_alloc_and_add_folio+0x4a0/0x1080 mm/shmem.c:1838 shmem_get_folio_gfp+0x621/0x1840 mm/shmem.c:2358 shmem_get_folio mm/shmem.c:2464 [inline] shmem_write_begin+0x165/0x350 mm/shmem.c:3120 generic_perform_write+0x346/0x990 mm/filemap.c:4046 shmem_file_write_iter+0xf9/0x120 mm/shmem.c:3296 new_sync_write fs/read_write.c:586 [inline] vfs_write+0xaeb/0xd30 fs/read_write.c:679 ksys_write+0x18f/0x2b0 fs/read_write.c:731 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 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(&per_cpu_ptr(pool->acomp_ctx, cpu)->mutex); lock(fs_reclaim); lock(&per_cpu_ptr(pool->acomp_ctx, cpu)->mutex); *** DEADLOCK *** 3 locks held by syz.3.19/5622: #0: ffff88801baec420 (sb_writers#5){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2964 [inline] #0: ffff88801baec420 (sb_writers#5){.+.+}-{0:0}, at: vfs_write+0x225/0xd30 fs/read_write.c:675 #1: ffff8880599b3080 (&sb->s_type->i_mutex_key#12){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:818 [inline] #1: ffff8880599b3080 (&sb->s_type->i_mutex_key#12){+.+.}-{4:4}, at: shmem_file_write_iter+0x80/0x120 mm/shmem.c:3286 #2: ffffffff8ea36f00 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:3926 [inline] #2: ffffffff8ea36f00 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim+0xd4/0x3c0 mm/page_alloc.c:3951 stack backtrace: CPU: 0 UID: 0 PID: 5622 Comm: syz.3.19 Not tainted 6.13.0-rc7-syzkaller-00149-g9bffa1ad25b8 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2206 check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 acomp_ctx_get_cpu_lock mm/zswap.c:899 [inline] zswap_compress mm/zswap.c:931 [inline] zswap_store_page mm/zswap.c:1456 [inline] zswap_store+0xa3b/0x1c30 mm/zswap.c:1563 swap_writepage+0x647/0xce0 mm/page_io.c:279 shmem_writepage+0x1248/0x1610 mm/shmem.c:1579 pageout mm/vmscan.c:696 [inline] shrink_folio_list+0x3b68/0x5ca0 mm/vmscan.c:1374 evict_folios+0x3c92/0x58c0 mm/vmscan.c:4600 try_to_shrink_lruvec+0x9a6/0xc70 mm/vmscan.c:4799 shrink_one+0x3b9/0x850 mm/vmscan.c:4844 shrink_many mm/vmscan.c:4907 [inline] lru_gen_shrink_node mm/vmscan.c:4985 [inline] shrink_node+0x37c5/0x3e50 mm/vmscan.c:5966 shrink_zones mm/vmscan.c:6225 [inline] do_try_to_free_pages+0x78c/0x1cf0 mm/vmscan.c:6287 try_to_free_pages+0x47c/0x1050 mm/vmscan.c:6537 __perform_reclaim mm/page_alloc.c:3929 [inline] __alloc_pages_direct_reclaim+0x178/0x3c0 mm/page_alloc.c:3951 __alloc_pages_slowpath+0x764/0x1020 mm/page_alloc.c:4382 __alloc_pages_noprof+0x49b/0x710 mm/page_alloc.c:4766 alloc_pages_mpol_noprof+0x3e1/0x780 mm/mempolicy.c:2269 folio_alloc_mpol_noprof+0x36/0x50 mm/mempolicy.c:2288 shmem_alloc_folio mm/shmem.c:1799 [inline] shmem_alloc_and_add_folio+0x4a0/0x1080 mm/shmem.c:1838 shmem_get_folio_gfp+0x621/0x1840 mm/shmem.c:2358 shmem_get_folio mm/shmem.c:2464 [inline] shmem_write_begin+0x165/0x350 mm/shmem.c:3120 generic_perform_write+0x346/0x990 mm/filemap.c:4046 shmem_file_write_iter+0xf9/0x120 mm/shmem.c:3296 new_sync_write fs/read_write.c:586 [inline] vfs_write+0xaeb/0xd30 fs/read_write.c:679 ksys_write+0x18f/0x2b0 fs/read_write.c:731 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: 0033:0x7f04379847df Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48 RSP: 002b:00007ffd75c007f0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007f04379847df RDX: 0000000001000000 RSI: 00007f042e600000 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 00000000000060e7 R10: 000000000000077c R11: 0000000000000293 R12: 0000000000000003 R13: 00007ffd75c008f0 R14: 00007ffd75c008b0 R15: 00007f042e600000 syz.3.19 (5622) used greatest stack depth: 16816 bytes left