file system panic on -current (amd64)

[Paul Goyette <paul%whooppee.com@localhost>]

I just experienced a rather nasty panic.  Kernel and userland are both
built from sources updated on 2017-07-20 at 01:01:55 (so, just a bit
more than a week ago).

The panic occurred while I was running a dump(8) on my /var using an
"internal fss(8) snapshot" with the command

	dump -0au -h 0 -X -f- /var | gzip -9 > var.dump.gz

At the same time I ran

	cd /var ; du -s *

in another session, and promptly got the following panic traceback
(manually transcribed - my USB keyboard attached via XHCI doesn't
play nicely with ddb):

	wapbl_stop
	wapbl_begin + 0x5b
	genfs_do_putpages + x1014
	VOP_PUTPAGES + 0x3a
	ffs_full_fsync + 0xe5
	ffs_fsync + 0x3a
	VOP_FSYNC + 0x3a
	sched_sync + 0x198

Has anyone seen this before?




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| Paul Goyette     | PGP Key fingerprint:     | E-mail addresses:          |
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