====================================================== WARNING: possible circular locking dependency detected 6.13.0-rc7-syzkaller-00149-g9bffa1ad25b8 #0 Not tainted ------------------------------------------------------ syz-executor/5360 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 vm_area_alloc_pages mm/vmalloc.c:3591 [inline] __vmalloc_area_node mm/vmalloc.c:3669 [inline] __vmalloc_node_range_noprof+0x9c9/0x1380 mm/vmalloc.c:3846 vmalloc_user_noprof+0x74/0x80 mm/vmalloc.c:4000 kcov_ioctl+0x56/0x640 kernel/kcov.c:716 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892 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 *** 1 lock held by syz-executor/5360: #0: ffffffff8ea36f00 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:3926 [inline] #0: ffffffff8ea36f00 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim+0xd4/0x3c0 mm/page_alloc.c:3951 stack backtrace: CPU: 0 UID: 0 PID: 5360 Comm: syz-executor 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 vm_area_alloc_pages mm/vmalloc.c:3591 [inline] __vmalloc_area_node mm/vmalloc.c:3669 [inline] __vmalloc_node_range_noprof+0x9c9/0x1380 mm/vmalloc.c:3846 vmalloc_user_noprof+0x74/0x80 mm/vmalloc.c:4000 kcov_ioctl+0x56/0x640 kernel/kcov.c:716 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892 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: 0033:0x7f9684d8592b Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00 RSP: 002b:00007ffd6b9b1400 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000080000 RCX: 00007f9684d8592b RDX: 0000000000080000 RSI: ffffffff80086301 RDI: 00000000000000dc RBP: 00007f9684f763b8 R08: 00000000000000da R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000 syz-executor (5360) used greatest stack depth: 18096 bytes left