libbpf: Fix btf dump error for BTF_KIND_FWD #54
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February 23, 2022 14:00
If a FWD appears in the BTF before a STRUCT with the same name, the
STRUCT is dumped with a conflicted name:
$ bpftool btf dump file vmlinux format raw | grep "'unix_sock'"
[81287] FWD 'unix_sock' fwd_kind=struct
[89336] STRUCT 'unix_sock' size=1024 vlen=14
$ bpftool btf dump file vmlinux format c | grep "struct unix_sock"
struct unix_sock;
struct unix_sock___2 { <--- conflict, the "___2" is unexpected
struct unix_sock___2 *unix_sk;
Fixes: 351131b ("libbpf: add btf_dump API for BTF-to-C conversion")
Signed-off-by: Xu Kuohai <[email protected]>
Acked-by: Song Liu <[email protected]>
Update btf_dump test case for conflict FWD and STRUCT name. Signed-off-by: Xu Kuohai <[email protected]> Acked-by: Song Liu <[email protected]>
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At least one diff in series https://patchwork.kernel.org/project/netdevbpf/list/?series=616605 expired. Closing PR. |
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…_transaction() We are seeing crashes similar to the following trace: [38.969182] WARNING: CPU: 20 PID: 2105 at fs/btrfs/relocation.c:4070 btrfs_relocate_block_group+0x2dc/0x340 [btrfs] [38.973556] CPU: 20 PID: 2105 Comm: btrfs Not tainted 5.17.0-rc4 #54 [38.974580] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 [38.976539] RIP: 0010:btrfs_relocate_block_group+0x2dc/0x340 [btrfs] [38.980336] RSP: 0000:ffffb0dd42e03c20 EFLAGS: 00010206 [38.981218] RAX: ffff96cfc4ede800 RBX: ffff96cfc3ce0000 RCX: 000000000002ca14 [38.982560] RDX: 0000000000000000 RSI: 4cfd109a0bcb5d7f RDI: ffff96cfc3ce0360 [38.983619] RBP: ffff96cfc309c000 R08: 0000000000000000 R09: 0000000000000000 [38.984678] R10: ffff96cec0000001 R11: ffffe84c80000000 R12: ffff96cfc4ede800 [38.985735] R13: 0000000000000000 R14: 0000000000000000 R15: ffff96cfc3ce0360 [38.987146] FS: 00007f11c15218c0(0000) GS:ffff96d6dfb00000(0000) knlGS:0000000000000000 [38.988662] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [38.989398] CR2: 00007ffc922c8e60 CR3: 00000001147a6001 CR4: 0000000000370ee0 [38.990279] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [38.991219] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [38.992528] Call Trace: [38.992854] <TASK> [38.993148] btrfs_relocate_chunk+0x27/0xe0 [btrfs] [38.993941] btrfs_balance+0x78e/0xea0 [btrfs] [38.994801] ? vsnprintf+0x33c/0x520 [38.995368] ? __kmalloc_track_caller+0x351/0x440 [38.996198] btrfs_ioctl_balance+0x2b9/0x3a0 [btrfs] [38.997084] btrfs_ioctl+0x11b0/0x2da0 [btrfs] [38.997867] ? mod_objcg_state+0xee/0x340 [38.998552] ? seq_release+0x24/0x30 [38.999184] ? proc_nr_files+0x30/0x30 [38.999654] ? call_rcu+0xc8/0x2f0 [39.000228] ? __x64_sys_ioctl+0x84/0xc0 [39.000872] ? btrfs_ioctl_get_supported_features+0x30/0x30 [btrfs] [39.001973] __x64_sys_ioctl+0x84/0xc0 [39.002566] do_syscall_64+0x3a/0x80 [39.003011] entry_SYSCALL_64_after_hwframe+0x44/0xae [39.003735] RIP: 0033:0x7f11c166959b [39.007324] RSP: 002b:00007fff2543e998 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [39.008521] RAX: ffffffffffffffda RBX: 00007f11c1521698 RCX: 00007f11c166959b [39.009833] RDX: 00007fff2543ea40 RSI: 00000000c4009420 RDI: 0000000000000003 [39.011270] RBP: 0000000000000003 R08: 0000000000000013 R09: 00007f11c16f94e0 [39.012581] R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff25440df3 [39.014046] R13: 0000000000000000 R14: 00007fff2543ea40 R15: 0000000000000001 [39.015040] </TASK> [39.015418] ---[ end trace 0000000000000000 ]--- [43.131559] ------------[ cut here ]------------ [43.132234] kernel BUG at fs/btrfs/extent-tree.c:2717! [43.133031] invalid opcode: 0000 [#1] PREEMPT SMP PTI [43.133702] CPU: 1 PID: 1839 Comm: btrfs Tainted: G W 5.17.0-rc4 #54 [43.134863] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 [43.136426] RIP: 0010:unpin_extent_range+0x37a/0x4f0 [btrfs] [43.139913] RSP: 0000:ffffb0dd4216bc70 EFLAGS: 00010246 [43.140629] RAX: 0000000000000000 RBX: ffff96cfc34490f8 RCX: 0000000000000001 [43.141604] RDX: 0000000080000001 RSI: 0000000051d00000 RDI: 00000000ffffffff [43.142645] RBP: 0000000000000000 R08: 0000000000000000 R09: ffff96cfd07dca50 [43.143669] R10: ffff96cfc46e8a00 R11: fffffffffffec000 R12: 0000000041d00000 [43.144657] R13: ffff96cfc3ce0000 R14: ffffb0dd4216bd08 R15: 0000000000000000 [43.145686] FS: 00007f7657dd68c0(0000) GS:ffff96d6df640000(0000) knlGS:0000000000000000 [43.146808] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [43.147584] CR2: 00007f7fe81bf5b0 CR3: 00000001093ee004 CR4: 0000000000370ee0 [43.148589] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [43.149581] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [43.150559] Call Trace: [43.150904] <TASK> [43.151253] btrfs_finish_extent_commit+0x88/0x290 [btrfs] [43.152127] btrfs_commit_transaction+0x74f/0xaa0 [btrfs] [43.152932] ? btrfs_attach_transaction_barrier+0x1e/0x50 [btrfs] [43.153786] btrfs_ioctl+0x1edc/0x2da0 [btrfs] [43.154475] ? __check_object_size+0x150/0x170 [43.155170] ? preempt_count_add+0x49/0xa0 [43.155753] ? __x64_sys_ioctl+0x84/0xc0 [43.156437] ? btrfs_ioctl_get_supported_features+0x30/0x30 [btrfs] [43.157456] __x64_sys_ioctl+0x84/0xc0 [43.157980] do_syscall_64+0x3a/0x80 [43.158543] entry_SYSCALL_64_after_hwframe+0x44/0xae [43.159231] RIP: 0033:0x7f7657f1e59b [43.161819] RSP: 002b:00007ffda5cd1658 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [43.162702] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f7657f1e59b [43.163526] RDX: 0000000000000000 RSI: 0000000000009408 RDI: 0000000000000003 [43.164358] RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000 [43.165208] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [43.166029] R13: 00005621b91c3232 R14: 00005621b91ba580 R15: 00007ffda5cd1800 [43.166863] </TASK> [43.167125] Modules linked in: btrfs blake2b_generic xor pata_acpi ata_piix libata raid6_pq scsi_mod libcrc32c virtio_net virtio_rng net_failover rng_core failover scsi_common [43.169552] ---[ end trace 0000000000000000 ]--- [43.171226] RIP: 0010:unpin_extent_range+0x37a/0x4f0 [btrfs] [43.174767] RSP: 0000:ffffb0dd4216bc70 EFLAGS: 00010246 [43.175600] RAX: 0000000000000000 RBX: ffff96cfc34490f8 RCX: 0000000000000001 [43.176468] RDX: 0000000080000001 RSI: 0000000051d00000 RDI: 00000000ffffffff [43.177357] RBP: 0000000000000000 R08: 0000000000000000 R09: ffff96cfd07dca50 [43.178271] R10: ffff96cfc46e8a00 R11: fffffffffffec000 R12: 0000000041d00000 [43.179178] R13: ffff96cfc3ce0000 R14: ffffb0dd4216bd08 R15: 0000000000000000 [43.180071] FS: 00007f7657dd68c0(0000) GS:ffff96d6df800000(0000) knlGS:0000000000000000 [43.181073] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [43.181808] CR2: 00007fe09905f010 CR3: 00000001093ee004 CR4: 0000000000370ee0 [43.182706] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [43.183591] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 We first hit the WARN_ON(rc->block_group->pinned > 0) in btrfs_relocate_block_group() and then the BUG_ON(!cache) in unpin_extent_range(). This tells us that we are exiting relocation and removing the block group with bytes still pinned for that block group. This is supposed to be impossible: the last thing relocate_block_group() does is commit the transaction to get rid of pinned extents. Commit d0c2f4f ("btrfs: make concurrent fsyncs wait less when waiting for a transaction commit") introduced an optimization so that commits from fsync don't have to wait for the previous commit to unpin extents. This was only intended to affect fsync, but it inadvertently made it possible for any commit to skip waiting for the previous commit to unpin. This is because if a call to btrfs_commit_transaction() finds that another thread is already committing the transaction, it waits for the other thread to complete the commit and then returns. If that other thread was in fsync, then it completes the commit without completing the previous commit. This makes the following sequence of events possible: Thread 1____________________|Thread 2 (fsync)_____________________|Thread 3 (balance)___________________ btrfs_commit_transaction(N) | | btrfs_run_delayed_refs | | pin extents | | ... | | state = UNBLOCKED |btrfs_sync_file | | btrfs_start_transaction(N + 1) |relocate_block_group | | btrfs_join_transaction(N + 1) | btrfs_commit_transaction(N + 1) | ... | trans->state = COMMIT_START | | | btrfs_commit_transaction(N + 1) | | wait_for_commit(N + 1, COMPLETED) | wait_for_commit(N, SUPER_COMMITTED)| state = SUPER_COMMITTED | ... | btrfs_finish_extent_commit| | unpin_extent_range() | trans->state = COMPLETED | | | return | | ... | |Thread 1 isn't done, so pinned > 0 | |and we WARN | | | |btrfs_remove_block_group unpin_extent_range() | | Thread 3 removed the | | block group, so we BUG| | There are other sequences involving SUPER_COMMITTED transactions that can cause a similar outcome. We could fix this by making relocation explicitly wait for unpinning, but there may be other cases that need it. Josef mentioned ENOSPC flushing and the free space cache inode as other potential victims. Rather than playing whack-a-mole, this fix is conservative and makes all commits not in fsync wait for all previous transactions, which is what the optimization intended. Fixes: d0c2f4f ("btrfs: make concurrent fsyncs wait less when waiting for a transaction commit") CC: [email protected] # 5.15+ Reviewed-by: Filipe Manana <[email protected]> Signed-off-by: Omar Sandoval <[email protected]> Signed-off-by: David Sterba <[email protected]>
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Commit 4fe8158 ("ixgbe: let the xdpdrv work with more than 64 cpus") adds support to allow XDP programs to run on systems with more than 64 CPUs by locking the XDP TX rings and indexing them using cpu % 64 (IXGBE_MAX_XDP_QS). Upon trying this out patch on a system with more than 64 cores, the kernel paniced with an array-index-out-of-bounds at the return in ixgbe_determine_xdp_ring in ixgbe.h, which means ixgbe_determine_xdp_q_idx was just returning the cpu instead of cpu % IXGBE_MAX_XDP_QS. An example splat: ========================================================================== UBSAN: array-index-out-of-bounds in /var/lib/dkms/ixgbe/5.18.6+focal-1/build/src/ixgbe.h:1147:26 index 65 is out of range for type 'ixgbe_ring *[64]' ========================================================================== BUG: kernel NULL pointer dereference, address: 0000000000000058 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] SMP NOPTI CPU: 65 PID: 408 Comm: ksoftirqd/65 Tainted: G IOE 5.15.0-48-generic #54~20.04.1-Ubuntu Hardware name: Dell Inc. PowerEdge R640/0W23H8, BIOS 2.5.4 01/13/2020 RIP: 0010:ixgbe_xmit_xdp_ring+0x1b/0x1c0 [ixgbe] Code: 3b 52 d4 cf e9 42 f2 ff ff 66 0f 1f 44 00 00 0f 1f 44 00 00 55 b9 00 00 00 00 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 ec 08 <44> 0f b7 47 58 0f b7 47 5a 0f b7 57 54 44 0f b7 76 08 66 41 39 c0 RSP: 0018:ffffbc3fcd88fcb0 EFLAGS: 00010282 RAX: ffff92a253260980 RBX: ffffbc3fe68b00a0 RCX: 0000000000000000 RDX: ffff928b5f659000 RSI: ffff928b5f659000 RDI: 0000000000000000 RBP: ffffbc3fcd88fce0 R08: ffff92b9dfc20580 R09: 0000000000000001 R10: 3d3d3d3d3d3d3d3d R11: 3d3d3d3d3d3d3d3d R12: 0000000000000000 R13: ffff928b2f0fa8c0 R14: ffff928b9be20050 R15: 000000000000003c FS: 0000000000000000(0000) GS:ffff92b9dfc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000058 CR3: 000000011dd6a002 CR4: 00000000007706e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: <TASK> ixgbe_poll+0x103e/0x1280 [ixgbe] ? sched_clock_cpu+0x12/0xe0 __napi_poll+0x30/0x160 net_rx_action+0x11c/0x270 __do_softirq+0xda/0x2ee run_ksoftirqd+0x2f/0x50 smpboot_thread_fn+0xb7/0x150 ? sort_range+0x30/0x30 kthread+0x127/0x150 ? set_kthread_struct+0x50/0x50 ret_from_fork+0x1f/0x30 </TASK> I think this is how it happens: Upon loading the first XDP program on a system with more than 64 CPUs, ixgbe_xdp_locking_key is incremented in ixgbe_xdp_setup. However, immediately after this, the rings are reconfigured by ixgbe_setup_tc. ixgbe_setup_tc calls ixgbe_clear_interrupt_scheme which calls ixgbe_free_q_vectors which calls ixgbe_free_q_vector in a loop. ixgbe_free_q_vector decrements ixgbe_xdp_locking_key once per call if it is non-zero. Commenting out the decrement in ixgbe_free_q_vector stopped my system from panicing. I suspect to make the original patch work, I would need to load an XDP program and then replace it in order to get ixgbe_xdp_locking_key back above 0 since ixgbe_setup_tc is only called when transitioning between XDP and non-XDP ring configurations, while ixgbe_xdp_locking_key is incremented every time ixgbe_xdp_setup is called. Also, ixgbe_setup_tc can be called via ethtool --set-channels, so this becomes another path to decrement ixgbe_xdp_locking_key to 0 on systems with more than 64 CPUs. Since ixgbe_xdp_locking_key only protects the XDP_TX path and is tied to the number of CPUs present, there is no reason to disable it upon unloading an XDP program. To avoid confusion, I have moved enabling ixgbe_xdp_locking_key into ixgbe_sw_init, which is part of the probe path. Fixes: 4fe8158 ("ixgbe: let the xdpdrv work with more than 64 cpus") Signed-off-by: John Hickey <[email protected]> Reviewed-by: Maciej Fijalkowski <[email protected]> Tested-by: Chandan Kumar Rout <[email protected]> (A Contingent Worker at Intel) Signed-off-by: Tony Nguyen <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Paolo Abeni <[email protected]>
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Since we may hold gic_lock in hardirq context, use raw spinlock makes more sense given that it is for low-level interrupt handling routine and the critical section is small. Fixes BUG: [ 0.426106] ============================= [ 0.426257] [ BUG: Invalid wait context ] [ 0.426422] 6.3.0-rc7-next-20230421-dirty #54 Not tainted [ 0.426638] ----------------------------- [ 0.426766] swapper/0/1 is trying to lock: [ 0.426954] ffffffff8104e7b8 (gic_lock){....}-{3:3}, at: gic_set_type+0x30/08 Fixes: 95150ae ("irqchip: mips-gic: Implement irq_set_type callback") Cc: [email protected] Signed-off-by: Jiaxun Yang <[email protected]> Reviewed-by: Serge Semin <[email protected]> Tested-by: Serge Semin <[email protected]> Signed-off-by: Marc Zyngier <[email protected]> Link: https://lore.kernel.org/r/[email protected]
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9f74a3d ("ice: Fix VF Reset paths when interface in a failed over aggregate"), the ice driver has acquired the LAG mutex in ice_reset_vf(). The commit placed this lock acquisition just prior to the acquisition of the VF configuration lock. If ice_reset_vf() acquires the configuration lock via the ICE_VF_RESET_LOCK flag, this could deadlock with ice_vc_cfg_qs_msg() because it always acquires the locks in the order of the VF configuration lock and then the LAG mutex. Lockdep reports this violation almost immediately on creating and then removing 2 VF: ====================================================== WARNING: possible circular locking dependency detected 6.8.0-rc6 #54 Tainted: G W O ------------------------------------------------------ kworker/60:3/6771 is trying to acquire lock: ff40d43e099380a0 (&vf->cfg_lock){+.+.}-{3:3}, at: ice_reset_vf+0x22f/0x4d0 [ice] but task is already holding lock: ff40d43ea1961210 (&pf->lag_mutex){+.+.}-{3:3}, at: ice_reset_vf+0xb7/0x4d0 [ice] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&pf->lag_mutex){+.+.}-{3:3}: __lock_acquire+0x4f8/0xb40 lock_acquire+0xd4/0x2d0 __mutex_lock+0x9b/0xbf0 ice_vc_cfg_qs_msg+0x45/0x690 [ice] ice_vc_process_vf_msg+0x4f5/0x870 [ice] __ice_clean_ctrlq+0x2b5/0x600 [ice] ice_service_task+0x2c9/0x480 [ice] process_one_work+0x1e9/0x4d0 worker_thread+0x1e1/0x3d0 kthread+0x104/0x140 ret_from_fork+0x31/0x50 ret_from_fork_asm+0x1b/0x30 -> #0 (&vf->cfg_lock){+.+.}-{3:3}: check_prev_add+0xe2/0xc50 validate_chain+0x558/0x800 __lock_acquire+0x4f8/0xb40 lock_acquire+0xd4/0x2d0 __mutex_lock+0x9b/0xbf0 ice_reset_vf+0x22f/0x4d0 [ice] ice_process_vflr_event+0x98/0xd0 [ice] ice_service_task+0x1cc/0x480 [ice] process_one_work+0x1e9/0x4d0 worker_thread+0x1e1/0x3d0 kthread+0x104/0x140 ret_from_fork+0x31/0x50 ret_from_fork_asm+0x1b/0x30 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&pf->lag_mutex); lock(&vf->cfg_lock); lock(&pf->lag_mutex); lock(&vf->cfg_lock); *** DEADLOCK *** 4 locks held by kworker/60:3/6771: #0: ff40d43e05428b38 ((wq_completion)ice){+.+.}-{0:0}, at: process_one_work+0x176/0x4d0 #1: ff50d06e05197e58 ((work_completion)(&pf->serv_task)){+.+.}-{0:0}, at: process_one_work+0x176/0x4d0 #2: ff40d43ea1960e50 (&pf->vfs.table_lock){+.+.}-{3:3}, at: ice_process_vflr_event+0x48/0xd0 [ice] #3: ff40d43ea1961210 (&pf->lag_mutex){+.+.}-{3:3}, at: ice_reset_vf+0xb7/0x4d0 [ice] stack backtrace: CPU: 60 PID: 6771 Comm: kworker/60:3 Tainted: G W O 6.8.0-rc6 #54 Hardware name: Workqueue: ice ice_service_task [ice] Call Trace: <TASK> dump_stack_lvl+0x4a/0x80 check_noncircular+0x12d/0x150 check_prev_add+0xe2/0xc50 ? save_trace+0x59/0x230 ? add_chain_cache+0x109/0x450 validate_chain+0x558/0x800 __lock_acquire+0x4f8/0xb40 ? lockdep_hardirqs_on+0x7d/0x100 lock_acquire+0xd4/0x2d0 ? ice_reset_vf+0x22f/0x4d0 [ice] ? lock_is_held_type+0xc7/0x120 __mutex_lock+0x9b/0xbf0 ? ice_reset_vf+0x22f/0x4d0 [ice] ? ice_reset_vf+0x22f/0x4d0 [ice] ? rcu_is_watching+0x11/0x50 ? ice_reset_vf+0x22f/0x4d0 [ice] ice_reset_vf+0x22f/0x4d0 [ice] ? process_one_work+0x176/0x4d0 ice_process_vflr_event+0x98/0xd0 [ice] ice_service_task+0x1cc/0x480 [ice] process_one_work+0x1e9/0x4d0 worker_thread+0x1e1/0x3d0 ? __pfx_worker_thread+0x10/0x10 kthread+0x104/0x140 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x31/0x50 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1b/0x30 </TASK> To avoid deadlock, we must acquire the LAG mutex only after acquiring the VF configuration lock. Fix the ice_reset_vf() to acquire the LAG mutex only after we either acquire or check that the VF configuration lock is held. Fixes: 9f74a3d ("ice: Fix VF Reset paths when interface in a failed over aggregate") Signed-off-by: Jacob Keller <[email protected]> Reviewed-by: Dave Ertman <[email protected]> Reviewed-by: Mateusz Polchlopek <[email protected]> Tested-by: Przemek Kitszel <[email protected]> Tested-by: Rafal Romanowski <[email protected]> Signed-off-by: Tony Nguyen <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jakub Kicinski <[email protected]>
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May 29, 2025
If, during a mremap() operation for a hugetlb-backed memory mapping, copy_vma() fails after the source vma has been duplicated and opened (ie. vma_link() fails), the error is handled by closing the new vma. This updates the hugetlbfs reservation counter of the reservation map which at this point is referenced by both the source vma and the new copy. As a result, once the new vma has been freed and copy_vma() returns, the reservation counter for the source vma will be incorrect. This patch addresses this corner case by clearing the hugetlb private page reservation reference for the new vma and decrementing the reference before closing the vma, so that vma_close() won't update the reservation counter. This is also what copy_vma_and_data() does with the source vma if copy_vma() succeeds, so a helper function has been added to do the fixup in both functions. The issue was reported by a private syzbot instance and can be reproduced using the C reproducer in [1]. It's also a possible duplicate of public syzbot report [2]. The WARNING report is: ============================================================ page_counter underflow: -1024 nr_pages=1024 WARNING: CPU: 0 PID: 3287 at mm/page_counter.c:61 page_counter_cancel+0xf6/0x120 Modules linked in: CPU: 0 UID: 0 PID: 3287 Comm: repro__WARNING_ Not tainted 6.15.0-rc7+ #54 NONE Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-2-gc13ff2cd-prebuilt.qemu.org 04/01/2014 RIP: 0010:page_counter_cancel+0xf6/0x120 Code: ff 5b 41 5e 41 5f 5d c3 cc cc cc cc e8 f3 4f 8f ff c6 05 64 01 27 06 01 48 c7 c7 60 15 f8 85 48 89 de 4c 89 fa e8 2a a7 51 ff <0f> 0b e9 66 ff ff ff 44 89 f9 80 e1 07 38 c1 7c 9d 4c 81 RSP: 0018:ffffc900025df6a0 EFLAGS: 00010246 RAX: 2edfc409ebb44e00 RBX: fffffffffffffc00 RCX: ffff8880155f0000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: dffffc0000000000 R08: ffffffff81c4a23c R09: 1ffff1100330482a R10: dffffc0000000000 R11: ffffed100330482b R12: 0000000000000000 R13: ffff888058a882c0 R14: ffff888058a882c0 R15: 0000000000000400 FS: 0000000000000000(0000) GS:ffff88808fc53000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000004b33e0 CR3: 00000000076d6000 CR4: 00000000000006f0 Call Trace: <TASK> page_counter_uncharge+0x33/0x80 hugetlb_cgroup_uncharge_counter+0xcb/0x120 hugetlb_vm_op_close+0x579/0x960 ? __pfx_hugetlb_vm_op_close+0x10/0x10 remove_vma+0x88/0x130 exit_mmap+0x71e/0xe00 ? __pfx_exit_mmap+0x10/0x10 ? __mutex_unlock_slowpath+0x22e/0x7f0 ? __pfx_exit_aio+0x10/0x10 ? __up_read+0x256/0x690 ? uprobe_clear_state+0x274/0x290 ? mm_update_next_owner+0xa9/0x810 __mmput+0xc9/0x370 exit_mm+0x203/0x2f0 ? __pfx_exit_mm+0x10/0x10 ? taskstats_exit+0x32b/0xa60 do_exit+0x921/0x2740 ? do_raw_spin_lock+0x155/0x3b0 ? __pfx_do_exit+0x10/0x10 ? __pfx_do_raw_spin_lock+0x10/0x10 ? _raw_spin_lock_irq+0xc5/0x100 do_group_exit+0x20c/0x2c0 get_signal+0x168c/0x1720 ? __pfx_get_signal+0x10/0x10 ? schedule+0x165/0x360 arch_do_signal_or_restart+0x8e/0x7d0 ? __pfx_arch_do_signal_or_restart+0x10/0x10 ? __pfx___se_sys_futex+0x10/0x10 syscall_exit_to_user_mode+0xb8/0x2c0 do_syscall_64+0x75/0x120 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x422dcd Code: Unable to access opcode bytes at 0x422da3. RSP: 002b:00007ff266cdb208 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000001 RBX: 00007ff266cdbcdc RCX: 0000000000422dcd RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00000000004c7bec RBP: 00007ff266cdb220 R08: 203a6362696c6720 R09: 203a6362696c6720 R10: 0000200000c00000 R11: 0000000000000246 R12: ffffffffffffffd0 R13: 0000000000000002 R14: 00007ffe1cb5f520 R15: 00007ff266cbb000 </TASK> ============================================================ Link: https://lkml.kernel.org/r/20250523-warning_in_page_counter_cancel-v2-1-b6df1a8cfefd@igalia.com Link: https://people.igalia.com/rcn/kernel_logs/20250422__WARNING_in_page_counter_cancel__repro.c [1] Link: https://lore.kernel.org/all/[email protected]/ [2] Signed-off-by: Ricardo Cañuelo Navarro <[email protected]> Suggested-by: Lorenzo Stoakes <[email protected]> Reviewed-by: Liam R. Howlett <[email protected]> Cc: Florent Revest <[email protected]> Cc: Jann Horn <[email protected]> Cc: Oscar Salvador <[email protected]> Cc: Vlastimil Babka <[email protected]> Cc: <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
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Sep 11, 2025
When there are memory-only nodes (nodes without CPUs), these nodes are not properly initialized, causing kernel panic during boot. of_numa_init of_numa_parse_cpu_nodes node_set(nid, numa_nodes_parsed); of_numa_parse_memory_nodes In of_numa_parse_cpu_nodes, numa_nodes_parsed gets updated only for nodes containing CPUs. Memory-only nodes should have been updated in of_numa_parse_memory_nodes, but they weren't. Subsequently, when free_area_init() attempts to access NODE_DATA() for these uninitialized memory nodes, the kernel panics due to NULL pointer dereference. This can be reproduced on ARM64 QEMU with 1 CPU and 2 memory nodes: qemu-system-aarch64 \ -cpu host -nographic \ -m 4G -smp 1 \ -machine virt,accel=kvm,gic-version=3,iommu=smmuv3 \ -object memory-backend-ram,size=2G,id=mem0 \ -object memory-backend-ram,size=2G,id=mem1 \ -numa node,nodeid=0,memdev=mem0 \ -numa node,nodeid=1,memdev=mem1 \ -kernel $IMAGE \ -hda $DISK \ -append "console=ttyAMA0 root=/dev/vda rw earlycon" [ 0.000000] Booting Linux on physical CPU 0x0000000000 [0x481fd010] [ 0.000000] Linux version 6.17.0-rc1-00001-gabb4b3daf18c-dirty (yintirui@local) (gcc (GCC) 12.3.1, GNU ld (GNU Binutils) 2.41) #52 SMP PREEMPT Mon Aug 18 09:49:40 CST 2025 [ 0.000000] KASLR enabled [ 0.000000] random: crng init done [ 0.000000] Machine model: linux,dummy-virt [ 0.000000] efi: UEFI not found. [ 0.000000] earlycon: pl11 at MMIO 0x0000000009000000 (options '') [ 0.000000] printk: legacy bootconsole [pl11] enabled [ 0.000000] OF: reserved mem: Reserved memory: No reserved-memory node in the DT [ 0.000000] NODE_DATA(0) allocated [mem 0xbfffd9c0-0xbfffffff] [ 0.000000] node 1 must be removed before remove section 23 [ 0.000000] Zone ranges: [ 0.000000] DMA [mem 0x0000000040000000-0x00000000ffffffff] [ 0.000000] DMA32 empty [ 0.000000] Normal [mem 0x0000000100000000-0x000000013fffffff] [ 0.000000] Movable zone start for each node [ 0.000000] Early memory node ranges [ 0.000000] node 0: [mem 0x0000000040000000-0x00000000bfffffff] [ 0.000000] node 1: [mem 0x00000000c0000000-0x000000013fffffff] [ 0.000000] Initmem setup node 0 [mem 0x0000000040000000-0x00000000bfffffff] [ 0.000000] Unable to handle kernel NULL pointer dereference at virtual address 00000000000000a0 [ 0.000000] Mem abort info: [ 0.000000] ESR = 0x0000000096000004 [ 0.000000] EC = 0x25: DABT (current EL), IL = 32 bits [ 0.000000] SET = 0, FnV = 0 [ 0.000000] EA = 0, S1PTW = 0 [ 0.000000] FSC = 0x04: level 0 translation fault [ 0.000000] Data abort info: [ 0.000000] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 [ 0.000000] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 0.000000] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 0.000000] [00000000000000a0] user address but active_mm is swapper [ 0.000000] Internal error: Oops: 0000000096000004 [#1] SMP [ 0.000000] Modules linked in: [ 0.000000] CPU: 0 UID: 0 PID: 0 Comm: swapper Not tainted 6.17.0-rc1-00001-g760c6dabf762-dirty #54 PREEMPT [ 0.000000] Hardware name: linux,dummy-virt (DT) [ 0.000000] pstate: 800000c5 (Nzcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 0.000000] pc : free_area_init+0x50c/0xf9c [ 0.000000] lr : free_area_init+0x5c0/0xf9c [ 0.000000] sp : ffffa02ca0f33c00 [ 0.000000] x29: ffffa02ca0f33cb0 x28: 0000000000000000 x27: 0000000000000000 [ 0.000000] x26: 4ec4ec4ec4ec4ec5 x25: 00000000000c0000 x24: 00000000000c0000 [ 0.000000] x23: 0000000000040000 x22: 0000000000000000 x21: ffffa02ca0f3b368 [ 0.000000] x20: ffffa02ca14c7b98 x19: 0000000000000000 x18: 0000000000000002 [ 0.000000] x17: 000000000000cacc x16: 0000000000000001 x15: 0000000000000001 [ 0.000000] x14: 0000000080000000 x13: 0000000000000018 x12: 0000000000000002 [ 0.000000] x11: ffffa02ca0fd4f00 x10: ffffa02ca14bab20 x9 : ffffa02ca14bab38 [ 0.000000] x8 : 00000000000c0000 x7 : 0000000000000001 x6 : 0000000000000002 [ 0.000000] x5 : 0000000140000000 x4 : ffffa02ca0f33c90 x3 : ffffa02ca0f33ca0 [ 0.000000] x2 : ffffa02ca0f33c98 x1 : 0000000080000000 x0 : 0000000000000001 [ 0.000000] Call trace: [ 0.000000] free_area_init+0x50c/0xf9c (P) [ 0.000000] bootmem_init+0x110/0x1dc [ 0.000000] setup_arch+0x278/0x60c [ 0.000000] start_kernel+0x70/0x748 [ 0.000000] __primary_switched+0x88/0x90 [ 0.000000] Code: d503201f b98093e0 52800016 f8607a93 (f9405260) [ 0.000000] ---[ end trace 0000000000000000 ]--- [ 0.000000] Kernel panic - not syncing: Attempted to kill the idle task! [ 0.000000] ---[ end Kernel panic - not syncing: Attempted to kill the idle task! ]--- Link: https://lkml.kernel.org/r/[email protected] Fixes: 7675076 ("arch_numa: switch over to numa_memblks") Signed-off-by: Yin Tirui <[email protected]> Acked-by: David Hildenbrand <[email protected]> Acked-by: Mike Rapoport (Microsoft) <[email protected]> Reviewed-by: Kefeng Wang <[email protected]> Cc: Chen Jun <[email protected]> Cc: Dan Williams <[email protected]> Cc: Joanthan Cameron <[email protected]> Cc: Rob Herring <[email protected]> Cc: Saravana Kannan <[email protected]> Cc: <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
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Pull request for series with
subject: libbpf: Fix btf dump error for BTF_KIND_FWD
version: 1
url: https://patchwork.kernel.org/project/netdevbpf/list/?series=616605