Extracting prog: 2m52.614229665s Minimizing prog: 9m58.466718512s Simplifying prog options: 13m39.500848373s Extracting C: 5m41.443534948s Simplifying C: 0s extracting reproducer from 1 programs testing a last program of every proc single: executing 1 programs separately with timeout 30s testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:6 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_netfilter-sendmsg$NFT_BATCH-syz_emit_ethernet detailed listing: executing program 0: r0 = socket$nl_netfilter(0x10, 0x3, 0xc) sendmsg$NFT_BATCH(r0, &(0x7f00000000c0)={0x0, 0x0, &(0x7f0000000040)={&(0x7f0000000200)=ANY=[@ANYBLOB="140000001000010000000000000000000000000a20000000000a010300000000000000000100fffd0900010073797a300000000040000000030a01020000000000000000010000000900030073797a3200000000140004800800024032658aeb08000140000000010900010073797a300000000044000000060a010400000000000001040100000008000b40000000000900010073797a30000000001c000480180001800d00010073796e70726f7879000000000400028014000000110001"], 0xcc}}, 0x0) syz_emit_ethernet(0x36, &(0x7f0000000b80)={@local, @broadcast, @void, {@ipv4={0x800, @tcp={{0x5, 0x4, 0x0, 0x3b, 0x28, 0x0, 0x0, 0x0, 0x6, 0x0, @empty, @empty}, {{0x0, 0x4e29, 0x41424344, 0x41424344, 0x0, 0x0, 0x5, 0x16, 0x1, 0x0, 0x20}}}}}}, 0x0) program did not crash single: failed to extract reproducer single: executing 1 programs separately with timeout 6m0s testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:6 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_netfilter-sendmsg$NFT_BATCH-syz_emit_ethernet detailed listing: executing program 0: r0 = socket$nl_netfilter(0x10, 0x3, 0xc) sendmsg$NFT_BATCH(r0, &(0x7f00000000c0)={0x0, 0x0, &(0x7f0000000040)={&(0x7f0000000200)=ANY=[@ANYBLOB="140000001000010000000000000000000000000a20000000000a010300000000000000000100fffd0900010073797a300000000040000000030a01020000000000000000010000000900030073797a3200000000140004800800024032658aeb08000140000000010900010073797a300000000044000000060a010400000000000001040100000008000b40000000000900010073797a30000000001c000480180001800d00010073796e70726f7879000000000400028014000000110001"], 0xcc}}, 0x0) syz_emit_ethernet(0x36, &(0x7f0000000b80)={@local, @broadcast, @void, {@ipv4={0x800, @tcp={{0x5, 0x4, 0x0, 0x3b, 0x28, 0x0, 0x0, 0x0, 0x6, 0x0, @empty, @empty}, {{0x0, 0x4e29, 0x41424344, 0x41424344, 0x0, 0x0, 0x5, 0x16, 0x1, 0x0, 0x20}}}}}}, 0x0) program crashed: possible deadlock in zswap_store single: successfully extracted reproducer found reproducer with 3 syscalls minimizing guilty program testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:6 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_netfilter-sendmsg$NFT_BATCH detailed listing: executing program 0: r0 = socket$nl_netfilter(0x10, 0x3, 0xc) sendmsg$NFT_BATCH(r0, &(0x7f00000000c0)={0x0, 0x0, &(0x7f0000000040)={&(0x7f0000000200)=ANY=[@ANYBLOB="140000001000010000000000000000000000000a20000000000a010300000000000000000100fffd0900010073797a300000000040000000030a01020000000000000000010000000900030073797a3200000000140004800800024032658aeb08000140000000010900010073797a300000000044000000060a010400000000000001040100000008000b40000000000900010073797a30000000001c000480180001800d00010073796e70726f7879000000000400028014000000110001"], 0xcc}}, 0x0) program crashed: possible deadlock in zswap_store testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:6 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_netfilter detailed listing: executing program 0: socket$nl_netfilter(0x10, 0x3, 0xc) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:6 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): sendmsg$NFT_BATCH detailed listing: executing program 0: sendmsg$NFT_BATCH(0xffffffffffffffff, &(0x7f00000000c0)={0x0, 0x0, &(0x7f0000000040)={&(0x7f0000000200)=ANY=[@ANYBLOB="140000001000010000000000000000000000000a20000000000a010300000000000000000100fffd0900010073797a300000000040000000030a01020000000000000000010000000900030073797a3200000000140004800800024032658aeb08000140000000010900010073797a300000000044000000060a010400000000000001040100000008000b40000000000900010073797a30000000001c000480180001800d00010073796e70726f7879000000000400028014000000110001"], 0xcc}}, 0x0) program crashed: possible deadlock in zswap_store testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:6 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): sendmsg$NFT_BATCH detailed listing: executing program 0: sendmsg$NFT_BATCH(0xffffffffffffffff, 0x0, 0x0) program crashed: possible deadlock in zswap_store extracting C reproducer testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:6 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): sendmsg$NFT_BATCH program crashed: no output from test machine a never seen crash title: no output from test machine, ignore simplifying guilty program options testing program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:6 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): sendmsg$NFT_BATCH detailed listing: executing program 0: sendmsg$NFT_BATCH(0xffffffffffffffff, 0x0, 0x0) program crashed: possible deadlock in zswap_store extracting C reproducer testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:6 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): sendmsg$NFT_BATCH program crashed: no output from test machine a never seen crash title: no output from test machine, ignore testing program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): sendmsg$NFT_BATCH detailed listing: executing program 0: sendmsg$NFT_BATCH(0xffffffffffffffff, 0x0, 0x0) program did not crash reproducing took 32m37.671367878s repro crashed as (corrupted=false): ====================================================== WARNING: possible circular locking dependency detected 6.13.0-rc7-syzkaller-00149-g9bffa1ad25b8 #0 Not tainted ------------------------------------------------------ syz-executor/5364 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 alloc_slab_page+0x6a/0x110 mm/slub.c:2423 allocate_slab+0x1c0/0x2b0 mm/slub.c:2597 new_slab mm/slub.c:2642 [inline] ___slab_alloc+0xc27/0x14a0 mm/slub.c:3830 __slab_alloc+0x58/0xa0 mm/slub.c:3920 __slab_alloc_node mm/slub.c:3995 [inline] slab_alloc_node mm/slub.c:4156 [inline] __kmalloc_cache_noprof+0x27b/0x390 mm/slub.c:4324 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] nexthop_net_init+0x75/0x100 net/ipv4/nexthop.c:4024 ops_init+0x31e/0x590 net/core/net_namespace.c:138 setup_net+0x287/0x9e0 net/core/net_namespace.c:362 copy_net_ns+0x33f/0x570 net/core/net_namespace.c:516 create_new_namespaces+0x425/0x7b0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228 ksys_unshare+0x57d/0xa70 kernel/fork.c:3333 __do_sys_unshare kernel/fork.c:3404 [inline] __se_sys_unshare kernel/fork.c:3402 [inline] __x64_sys_unshare+0x38/0x40 kernel/fork.c:3402 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 *** 2 locks held by syz-executor/5364: #0: ffffffff8fca6b50 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512 #1: ffffffff8ea36f00 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:3926 [inline] #1: ffffffff8ea36f00 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim+0xd4/0x3c0 mm/page_alloc.c:3951 stack backtrace: CPU: 0 UID: 0 PID: 5364 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 alloc_slab_page+0x6a/0x110 mm/slub.c:2423 allocate_slab+0x1c0/0x2b0 mm/slub.c:2597 new_slab mm/slub.c:2642 [inline] ___slab_alloc+0xc27/0x14a0 mm/slub.c:3830 __slab_alloc+0x58/0xa0 mm/slub.c:3920 __slab_alloc_node mm/slub.c:3995 [inline] slab_alloc_node mm/slub.c:4156 [inline] __kmalloc_cache_noprof+0x27b/0x390 mm/slub.c:4324 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] nexthop_net_init+0x75/0x100 net/ipv4/nexthop.c:4024 ops_init+0x31e/0x590 net/core/net_namespace.c:138 setup_net+0x287/0x9e0 net/core/net_namespace.c:362 copy_net_ns+0x33f/0x570 net/core/net_namespace.c:516 create_new_namespaces+0x425/0x7b0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228 ksys_unshare+0x57d/0xa70 kernel/fork.c:3333 __do_sys_unshare kernel/fork.c:3404 [inline] __se_sys_unshare kernel/fork.c:3402 [inline] __x64_sys_unshare+0x38/0x40 kernel/fork.c:3402 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: 0033:0x7fd0c7b87527 Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 10 01 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fff4e4da958 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00007fd0c7d75f40 RCX: 00007fd0c7b87527 RDX: 00007fd0c7b85d29 RSI: 00007fff4e4da920 RDI: 0000000040000000 RBP: 00007fd0c7d76578 R08: 00007fd0c7d3a9d0 R09: 00007fd0c7d3a9d0 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006 R13: 0000000000000006 R14: 0000000000000009 R15: 0000000000000000 syz-executor (5364) used greatest stack depth: 17296 bytes left final repro crashed as (corrupted=false): ====================================================== WARNING: possible circular locking dependency detected 6.13.0-rc7-syzkaller-00149-g9bffa1ad25b8 #0 Not tainted ------------------------------------------------------ syz-executor/5364 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 alloc_slab_page+0x6a/0x110 mm/slub.c:2423 allocate_slab+0x1c0/0x2b0 mm/slub.c:2597 new_slab mm/slub.c:2642 [inline] ___slab_alloc+0xc27/0x14a0 mm/slub.c:3830 __slab_alloc+0x58/0xa0 mm/slub.c:3920 __slab_alloc_node mm/slub.c:3995 [inline] slab_alloc_node mm/slub.c:4156 [inline] __kmalloc_cache_noprof+0x27b/0x390 mm/slub.c:4324 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] nexthop_net_init+0x75/0x100 net/ipv4/nexthop.c:4024 ops_init+0x31e/0x590 net/core/net_namespace.c:138 setup_net+0x287/0x9e0 net/core/net_namespace.c:362 copy_net_ns+0x33f/0x570 net/core/net_namespace.c:516 create_new_namespaces+0x425/0x7b0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228 ksys_unshare+0x57d/0xa70 kernel/fork.c:3333 __do_sys_unshare kernel/fork.c:3404 [inline] __se_sys_unshare kernel/fork.c:3402 [inline] __x64_sys_unshare+0x38/0x40 kernel/fork.c:3402 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 *** 2 locks held by syz-executor/5364: #0: ffffffff8fca6b50 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512 #1: ffffffff8ea36f00 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:3926 [inline] #1: ffffffff8ea36f00 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim+0xd4/0x3c0 mm/page_alloc.c:3951 stack backtrace: CPU: 0 UID: 0 PID: 5364 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 alloc_slab_page+0x6a/0x110 mm/slub.c:2423 allocate_slab+0x1c0/0x2b0 mm/slub.c:2597 new_slab mm/slub.c:2642 [inline] ___slab_alloc+0xc27/0x14a0 mm/slub.c:3830 __slab_alloc+0x58/0xa0 mm/slub.c:3920 __slab_alloc_node mm/slub.c:3995 [inline] slab_alloc_node mm/slub.c:4156 [inline] __kmalloc_cache_noprof+0x27b/0x390 mm/slub.c:4324 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] nexthop_net_init+0x75/0x100 net/ipv4/nexthop.c:4024 ops_init+0x31e/0x590 net/core/net_namespace.c:138 setup_net+0x287/0x9e0 net/core/net_namespace.c:362 copy_net_ns+0x33f/0x570 net/core/net_namespace.c:516 create_new_namespaces+0x425/0x7b0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228 ksys_unshare+0x57d/0xa70 kernel/fork.c:3333 __do_sys_unshare kernel/fork.c:3404 [inline] __se_sys_unshare kernel/fork.c:3402 [inline] __x64_sys_unshare+0x38/0x40 kernel/fork.c:3402 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: 0033:0x7fd0c7b87527 Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 10 01 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fff4e4da958 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00007fd0c7d75f40 RCX: 00007fd0c7b87527 RDX: 00007fd0c7b85d29 RSI: 00007fff4e4da920 RDI: 0000000040000000 RBP: 00007fd0c7d76578 R08: 00007fd0c7d3a9d0 R09: 00007fd0c7d3a9d0 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006 R13: 0000000000000006 R14: 0000000000000009 R15: 0000000000000000 syz-executor (5364) used greatest stack depth: 17296 bytes left