From: "Marek Marczykowski-Górecki" <marmarek@invisiblethingslab.com>
To: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Cc: linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: kernel BUG at mm/slub.c:634 (kfree) when unbinding device from iwlwifi
Date: Wed, 15 Jul 2026 16:32:41 +0200 [thread overview]
Message-ID: <aleaCWlvrmiUcLhT@mail-itl> (raw)
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Hello,
I get a kernel panic when unbinding device (8086:0085) from the iwlwifi
driver (via writing to the "unbind" file in sysfs), while the wifi
connection is active. I can reproduce it on Thinkpad X230, but other
devices might be affected too. The specific crash is:
[ 286.908182] kernel BUG at mm/slub.c:634!
[ 286.908201] Oops: invalid opcode: 0000 [#1] SMP PTI
[ 286.908221] CPU: 1 UID: 0 PID: 1959 Comm: prepare-suspend Not tainted 6.18.15-1.qubes.fc41.x86_64 #1 PREEMPT(full)
[ 286.908255] Hardware name: Xen HVM domU, BIOS 4.19.4 03/17/2026
[ 286.908275] RIP: 0010:kfree+0x3a8/0x470
[ 286.908292] Code: 5d 41 5e 41 5f 5d e9 67 bb ff ff 4d 89 f1 41 b8 01 00 00 00 48 89 d9 48 89 da 4c 89 ee 4c 89 e7 e8 ad 2c 00 00 e9 bd fd ff ff <0f> 0b 89 c8 4c 8d 04 03 40 f6 c6 80 0f 84 41 ff ff ff 83 e6 08 0f
[ 286.908347] RSP: 0018:ffffcfce8280bb50 EFLAGS: 00010246
[ 286.908365] RAX: ffff8b2dcef2c800 RBX: ffff8b2dcef2c800 RCX: ffff8b2dcef2c830
[ 286.908389] RDX: 00000000000be001 RSI: 0000000000000000 RDI: ffff8b2dcef2c880
[ 286.908414] RBP: ffffcfce8280bba0 R08: ffff8b2dcef2c860 R09: 0000000000000000
[ 286.908438] R10: ffff8b2dcef2c860 R11: 0000000000000000 R12: ffff8b2dd2841600
[ 286.908462] R13: fffff077003bcb00 R14: ffffffffc093c480 R15: 0000000000000060
[ 286.908487] FS: 00007b10286cd740(0000) GS:ffff8b2e19c6c000(0000) knlGS:0000000000000000
[ 286.908511] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 286.908532] CR2: 00007fb93027bc70 CR3: 00000000034f0005 CR4: 00000000001706f0
[ 286.908559] Call Trace:
[ 286.908570] <TASK>
[ 286.908581] ? _raw_spin_unlock_bh+0xe/0x20
[ 286.908599] iwl_pcie_txq_free+0x130/0x170 [iwlwifi]
[ 286.908644] iwl_pcie_tx_free+0x66/0xe0 [iwlwifi]
[ 286.908681] iwl_trans_pcie_free+0x1df/0x250 [iwlwifi]
[ 286.908719] pci_device_remove+0x42/0xb0
[ 286.908736] device_release_driver_internal+0x19c/0x200
[ 286.908755] unbind_store+0xa1/0xb0
[ 286.908771] kernfs_fop_write_iter+0x150/0x200
[ 286.908790] vfs_write+0x25d/0x450
[ 286.908806] ksys_write+0x6b/0xe0
[ 286.908825] do_syscall_64+0x84/0x800
[ 286.908842] ? syscall_exit_work+0x108/0x140
[ 286.908861] ? do_syscall_64+0xbb/0x800
[ 286.908876] ? ksys_dup3+0x63/0xf0
[ 286.908892] ? syscall_exit_work+0x108/0x140
[ 286.911388] ? do_syscall_64+0xbb/0x800
[ 286.911408] ? do_sys_openat2+0xa4/0xe0
[ 286.911423] ? syscall_exit_work+0x108/0x140
[ 286.911443] ? do_syscall_64+0xbb/0x800
[ 286.911458] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 286.911477] RIP: 0033:0x7b102873ec5e
[ 286.911493] Code: 4d 89 d8 e8 34 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
[ 286.911549] RSP: 002b:00007ffd94bc3100 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 286.911575] RAX: ffffffffffffffda RBX: 00007b10288ba5c0 RCX: 00007b102873ec5e
[ 286.911600] RDX: 000000000000000d RSI: 00006385db4f8020 RDI: 0000000000000001
[ 286.911625] RBP: 00007ffd94bc3110 R08: 0000000000000000 R09: 0000000000000000
[ 286.911650] R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000000d
[ 286.911674] R13: 000000000000000d R14: 00006385db4f8020 R15: 00006385db4f5b30
[ 286.911701] </TASK>
[ 286.911711] Modules linked in: iwldvm iwlwifi mac80211 ehci_pci ehci_hcd nft_nat nft_flow_offload nf_flow_table_inet nf_flow_table qrtr nf_conntrack_netlink nft_reject_ipv6 nf_reject_ipv6 nft_reject_ipv4 nf_reject_ipv4 nft_reject nft_ct nft_masq nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nf_tables joydev libarc4 intel_rapl_msr intel_rapl_common polyval_clmulni ghash_clmulni_intel cfg80211 e1000e ata_generic rfkill i2c_piix4 pata_acpi i2c_smbus pcspkr floppy vfat fat serio_raw xen_scsiback target_core_mod xen_netback xen_privcmd xen_gntdev xen_gntalloc xen_blkback xen_evtchn i2c_dev fuse loop nfnetlink overlay xen_blkfront [last unloaded: iwlwifi]
[ 286.911967] ---[ end trace 0000000000000000 ]---
This is running in a VM (HVM) under Xen, with relevant PCI device
attached, but I don't think it's relevant for this bug.
I've got reports about the issue in Linux 6.18.15 initially (after
updating from 6.12), but later tests identified it's a regression
somewhere between 6.15.11 and 6.16.8.
The crash still happen on 7.0.14, although it looks different there:
[ 106.379541] ------------[ cut here ]------------
[ 106.379572] kernel BUG at mm/slub.c:542!
[ 106.379596] Oops: invalid opcode: 0000 [#1] SMP PTI
[ 106.379618] CPU: 1 UID: 0 PID: 240 Comm: kworker/1:2 Not tainted 7.0.14-1.qubes.fc41.x86_64 #1 PREEMPT(full)
[ 106.379656] Hardware name: Xen HVM domU, BIOS 4.19.4 06/09/2026
[ 106.379680] Workqueue: slub_flushwq flush_cpu_sheaves
[ 106.379711] RIP: 0010:build_detached_freelist+0x1d0/0x210
[ 106.379733] Code: 41 5c 41 5d c3 cc cc cc cc 31 d2 4d 85 c0 0f 85 b2 fe ff ff 48 89 04 24 e8 7d fd ff ff 48 c7 03 00 00 00 00 48 8b 04 24 eb d0 <0f> 0b 48 85 d2 74 e3 48 89 13 4c 8b 42 08 e9 8c fe ff ff 0f 0b 31
[ 106.379795] RSP: 0000:ffffcebd804c3c88 EFLAGS: 00010246
[ 106.379815] RAX: 000000000000001d RBX: ffffcebd804c3cb8 RCX: ffff8e6240fcf000
[ 106.379843] RDX: ffff8e6240fcf000 RSI: 000000000000001d RDI: 0000000000000003
[ 106.379870] RBP: ffffffff80000000 R08: 0000000080000000 R09: ffff8e6240fcf030
[ 106.379898] R10: ffffcebd804c3d10 R11: 0000000000000000 R12: ffff8e6242a68b00
[ 106.379925] R13: ffff8e6242a68aff R14: 000000000000001c R15: 0000000000000000
[ 106.379953] FS: 0000000000000000(0000) GS:ffff8e62a837a000(0000) knlGS:0000000000000000
[ 106.379981] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 106.380004] CR2: 0000767e599f2fd0 CR3: 000000000c1d2001 CR4: 00000000001706f0
[ 106.380035] Call Trace:
[ 106.380047] <TASK>
[ 106.380060] __kmem_cache_free_bulk.part.0+0x60/0xe0
[ 106.380085] __sheaf_flush_main_batch+0xa1/0xe0
[ 106.380110] flush_cpu_sheaves+0xc3/0xe0
[ 106.380129] process_one_work+0x198/0x390
[ 106.380149] worker_thread+0x1af/0x320
[ 106.380168] ? __pfx_worker_thread+0x10/0x10
[ 106.380190] kthread+0xe3/0x120
[ 106.380207] ? __pfx_kthread+0x10/0x10
[ 106.380223] ret_from_fork+0x19e/0x260
[ 106.380241] ? __pfx_kthread+0x10/0x10
[ 106.380257] ret_from_fork_asm+0x1a/0x30
[ 106.380276] </TASK>
[ 106.380287] Modules linked in: nft_nat nft_flow_offload nf_flow_table_inet nf_flow_table nf_conntrack_netlink nft_reject_ipv6 nf_reject_ipv6 qrtr nft_reject_ipv4 nf_reject_ipv4 nft_reject nft_ct nft_masq nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nf_tables vfat fat intel_rapl_msr iwldvm intel_rapl_common ghash_clmulni_intel mac80211 libarc4 iwlwifi joydev cfg80211 ehci_pci pcspkr e1000e ehci_hcd rfkill floppy ata_generic i2c_piix4 pata_acpi i2c_smbus serio_raw xen_scsiback target_core_mod xen_netback xen_privcmd xen_gntdev xen_gntalloc xen_blkback xen_evtchn i2c_dev loop fuse nfnetlink zram lz4hc_compress lz4_compress overlay xen_blkfront
[ 106.381851] ---[ end trace 0000000000000000 ]---
This one doesn't have obvious relation to iwlwifi, but I suspect it's at
least related.
There are some more call traces at
https://github.com/QubesOS/qubes-issues/issues/10845 but they look
pretty similar.
--
Best Regards,
Marek Marczykowski-Górecki
Invisible Things Lab
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next reply other threads:[~2026-07-15 14:32 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-07-15 14:32 Marek Marczykowski-Górecki [this message]
2026-07-15 17:22 ` kernel BUG at mm/slub.c:634 (kfree) when unbinding device from iwlwifi Korenblit, Miriam Rachel
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