Re: kern/53815: vnd+wapbl+snapshots panic

["J. Hannken-Illjes" <hannken%eis.cs.tu-bs.de@localhost>]

The following reply was made to PR kern/53815; it has been noted by GNATS.

From: "J. Hannken-Illjes" <hannken%eis.cs.tu-bs.de@localhost>
To: "gnats-bugs%netbsd.org@localhost" <gnats-bugs%NetBSD.org@localhost>
Cc: 
Subject: Re: kern/53815: vnd+wapbl+snapshots panic
Date: Mon, 31 Dec 2018 13:21:54 +0100

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 Usually VOP_STRATEGY() gets called from inside the file
 system.  Here the wapbl lock has already been taken.
 
 When vnd(4) is using VOP_STRATEGY() on a wapbl enabled
 file system this lock is not taken.
 
 I don't see a solution that works well in both cases.
 
 Workaround is to disable wapbl on file systems used
 as vnd backing store or configure the vnd device
 with "-i" to force regular file i/o.
 
 --
 J. Hannken-Illjes - hannken%eis.cs.tu-bs.de@localhost - TU Braunschweig
 
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