Subject: linux-next: boot failure after merge of the vfs-brauner tree

From: Stephen Rothwell <[email-masked]>
Date: Mon, 5 Feb 2024 16:15:15 +1100

Hi all,

After merging the vfs-brauner tree, today's linux-next build (powerpc
pseries_le_defconfig) failed like this:

[    2.498347][    T1] Loading compiled-in X.509 certificates
[    2.514931][   T53] BUG: Kernel NULL pointer dereference at 0x00000038
[    2.515067][   T53] Faulting instruction address: 0xc0000000011c9e14
[    2.515629][   T53] Oops: Kernel access of bad area, sig: 11 [#1]
[    2.515749][   T53] LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries
[    2.516160][   T53] Modules linked in:
[    2.516586][   T53] CPU: 0 PID: 53 Comm: cryptomgr_probe Not tainted 6.8.0-rc3-04019-g26b3eeef9e0f #1
[    2.516849][   T53] Hardware name: IBM pSeries (emulated by qemu) POWER8 (raw) 0x4d0200 0xf000004 of:SLOF,HEAD pSeries
[    2.517084][   T53] NIP:  c0000000011c9e14 LR: c0000000001dd7b4 CTR: c00000000029c820
[    2.517163][   T53] REGS: c00000000786fa00 TRAP: 0380   Not tainted  (6.8.0-rc3-04019-g26b3eeef9e0f)
[    2.517288][   T53] MSR:  8000000002009033 <SF,VEC,EE,ME,IR,DR,RI,LE>  CR: 28004208  XER: 20000000
[    2.517612][   T53] CFAR: c0000000001dd7b0 IRQMASK: 1 
[    2.517612][   T53] GPR00: c0000000001dd7b4 c00000000786fca0 c0000000015c9900 0000000000000038 
[    2.517612][   T53] GPR04: 0000000000000003 0000000000000001 0000000000000051 fffffffffffe0000 
[    2.517612][   T53] GPR08: 0000000000000000 0000000000000001 c0000000079554c8 0000000000002000 
[    2.517612][   T53] GPR12: c00000000029c820 c000000002b60000 c00000000018fa0c c00000000404cec0 
[    2.517612][   T53] GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 
[    2.517612][   T53] GPR20: 0000000000000000 0000000000000000 c000000006e0e580 0000000000000000 
[    2.517612][   T53] GPR24: c000000002951080 c000000002a0e848 0000000000000000 0000000000000051 
[    2.517612][   T53] GPR28: c0000000048cc100 0000000000000038 0000000000000001 0000000000000001 
[    2.518535][   T53] NIP [c0000000011c9e14] _raw_spin_lock_irqsave+0x34/0xc0
[    2.519499][   T53] LR [c0000000001dd7b4] __wake_up+0x44/0xa4
[    2.519797][   T53] Call Trace:
[    2.519944][   T53] [c00000000786fca0] [0000000000002000] 0x2000 (unreliable)
[    2.520411][   T53] [c00000000786fcd0] [c00000000786fd10] 0xc00000000786fd10
[    2.520523][   T53] [c00000000786fd20] [c00000000016d240] pidfd_wake_up_poll+0x50/0x64
[    2.520597][   T53] [c00000000786fd40] [c000000000189460] __change_pid+0x84/0x16c
[    2.520669][   T53] [c00000000786fd70] [c000000000158dec] release_task+0x338/0x788
[    2.520740][   T53] [c00000000786fe10] [c00000000015aa9c] do_exit+0x6d8/0xd38
[    2.520812][   T53] [c00000000786fef0] [c00000000018f9c4] kthread_exit+0x3c/0x40
[    2.521033][   T53] [c00000000786ff20] [c00000000023f2bc] __module_put_and_kthread_exit+0x38/0x3c
[    2.521120][   T53] [c00000000786ff50] [c00000000095cdc4] cryptomgr_probe+0xc8/0xcc
[    2.521204][   T53] [c00000000786ff90] [c00000000018fb3c] kthread+0x138/0x140
[    2.521283][   T53] [c00000000786ffe0] [c00000000000ded8] start_kernel_thread+0x14/0x18
[    2.521512][   T53] Code: 3842fb20 7c0802a6 60000000 fbe1fff8 f821ffd1 8bed0932 63e90001 992d0932 a12d0008 3ce0fffe 5529083c 61290001 <7d001829> 7d063879 40c20018 7d063838 
[    2.522412][   T53] ---[ end trace 0000000000000000 ]---
[    2.545459][   T53] pstore: backend (nvram) writing error (-1)
[    2.545630][   T53] 
[    2.545995][   T53] note: cryptomgr_probe[53] exited with irqs disabled
[    2.546329][   T53] Fixing recursive fault but reboot is needed!
[    2.560506][    T1] Loaded X.509 cert 'Build time autogenerated kernel key: fcc64ee53479274966d371cbdc225bca2574aaaf'

Bisected to commit

  7a1cac7d58e3 ("pidfd: convert to wake_up_poll()")

I have reverted that commit for today.

-- 
Cheers,
Stephen Rothwell