Bug 252801

Summary:	arm64: LOR msdosfs -> devfs
Product:	Base System	Reporter:	Gordon Bergling <gbe>
Component:	arm	Assignee:	freebsd-arm (Nobody) <freebsd-arm>
Status:	New ---
Severity:	Affects Some People	CC:	emaste
Priority:	---
Version:	CURRENT
Hardware:	Any
OS:	Any

Description Gordon Bergling freebsd_committer

2021-01-18 10:41:18 UTC

While working on a few config.txt issues on the RPi4B I noticed, that when you actual write to the file on the msdos partition the following LOR is reproducible be triggered.

kernel:  1st 0xffffa000224349f8 msdosfs (msdosfs, lockmgr) @ /tank/nfs_public/tiny/src/sys/kern/vfs_syscal
ls.c:3498
kernel:  2nd 0xffffa00022013628 devfs (devfs, lockmgr) @ /tank/nfs_public/tiny/src/sys/fs/msdosfs/msdosfs_
vnops.c:853
kernel: lock order msdosfs -> devfs attempted at:
kernel: #0 0xffff0000004c5774 at witness_checkorder+0xc50
kernel: #1 0xffff0000004296fc at lockmgr_xlock+0x50
kernel: #2 0xffff00000054feb8 at _vn_lock+0x54
kernel: #3 0xffff000000313d4c at msdosfs_fsync+0x58
kernel: #4 0xffff00000054bb74 at kern_fsync+0x194
kernel: #5 0xffff00000079037c at do_el0_sync+0x7cc
kernel: #6 0xffff00000076fa24 at handle_el0_sync+0x90