Re: Panic in 9.0_STABLE with ZFS module on DOMU PV with recent build

[Brad Spencer <brad%anduin.eldar.org@localhost>]

Jaromír Doleček <jaromir.dolecek%gmail.com@localhost> writes:

> OK, it seems what happens is that xbd_diskstart() routine gets a
> request for starting I/O bigger than it can handle. The NetBSD 9.0
> xbd(4) has a limit of 44 KB maximum I/O, and XEN3_DOMU has specific
> override for MAXPHYS to 32 KB for this reason.
>
> It seems the ZFS module does not take this into account, and is
> compiled with default 64 KB MAXPHYS.
>
> On -current xbd(4) was changed to remove this limitation, and works
> with default 64KB MAXPHYS. One option is then to just upgrade the
> kernel to -current. You can leave userland on 9.0. If that is not
> possible for you, you can build your own custom ZFS module with an
> override of MAXPHYS=32768, using still netbsd-9 sources.
>
> Jaromir


The following diff worked for me on a 2020-08-29 tree... thanks for the
work and the hint...

--- src/sys/modules/zfs/Makefile.zfsmod.DIST    2019-02-05 04:54:36.000000000 -0500
+++ src/sys/modules/zfs/Makefile.zfsmod 2020-09-10 18:35:34.683493656 -0400
@@ -135,5 +135,6 @@
 CPPFLAGS+=     -I${ZFSDIR}/dist/uts/common

 CPPFLAGS+=     -D_PROPLIB_ZFS_CONFLICT
+CPPFLAGS+=     -DMAXPHYS=32768

 NEED_ISYSTEM=  # duplicate headers, depends on -isystem to build




-- 
Brad Spencer - brad%anduin.eldar.org@localhost - KC8VKS - http://anduin.eldar.org