On Wed, 16 Aug 2023 09:56:23 -1000, Tejun Heo wrote:
> blk-iocost sometimes causes the following crash:
>
> BUG: kernel NULL pointer dereference, address: 00000000000000e0
> ...
> RIP: 0010:_raw_spin_lock+0x17/0x30
> Code: be 01 02 00 00 e8 79 38 39 ff 31 d2 89 d0 5d c3 0f 1f 00 0f 1f 44 00 00 55 48 89 e5 65 ff 05 48 d0 34 7e b9 01 00 00 00 31 c0 <f0> 0f b1 0f 75 02 5d c3 89 c6 e8 ea 04 00 00 5d c3 0f 1f 84 00 00
> RSP: 0018:ffffc900023b3d40 EFLAGS: 00010046
> RAX: 0000000000000000 RBX: 00000000000000e0 RCX: 0000000000000001
> RDX: ffffc900023b3d20 RSI: ffffc900023b3cf0 RDI: 00000000000000e0
> RBP: ffffc900023b3d40 R08: ffffc900023b3c10 R09: 0000000000000003
> R10: 0000000000000064 R11: 000000000000000a R12: ffff888102337000
> R13: fffffffffffffff2 R14: ffff88810af408c8 R15: ffff8881070c3600
> FS: 00007faaaf364fc0(0000) GS:ffff88842fdc0000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00000000000000e0 CR3: 00000001097b1000 CR4: 0000000000350ea0
> Call Trace:
> <TASK>
> ioc_weight_write+0x13d/0x410
> cgroup_file_write+0x7a/0x130
> kernfs_fop_write_iter+0xf5/0x170
> vfs_write+0x298/0x370
> ksys_write+0x5f/0xb0
> __x64_sys_write+0x1b/0x20
> do_syscall_64+0x3d/0x80
> entry_SYSCALL_64_after_hwframe+0x46/0xb0
>
> [...]
Applied, thanks!
[1/1] blk-cgroup: Fix NULL deref caused by blkg_policy_data being installed before init
commit: ec14a87ee1999b19d8b7ed0fa95fea80644624ae
Best regards,
--
Jens Axboe
