Re: lvm+DIOCCACHESYNC woes

[Adam Hamsik <haaaad%gmail.com@localhost>]

On Jun,Monday 6 2011, at 12:26 PM, Hugo Silva wrote:

> Hello,
> 
> Some days ago I installed a new -current 5.99.52 Xen dom0 from one of
> the available nyftp images.
> 
> Just noticed this in messages @ the dom0:
> /netbsd: xbdback backend/vbd/8/1: DIOCCACHESYNC returned -4
> /netbsd: xbdback backend/vbd/8/1: DIOCCACHESYNC returned -4
> last message repeated 10 times
> 
> This rang a bell, and indeed:
> http://mail-index.netbsd.org/port-xen/2010/05/12/msg005998.html

Right now LVM just sends DIOCCACHESYNC to physical device behind

dm_target_linear.c::dm_target_linear_sync

return VOP_IOCTL(tlc->pdev->pdev_vnode,  DIOCCACHESYNC, &cmd,
            FREAD|FWRITE, kauth_cred_get());

So to me it looks like this error comes from disk device itself.

> Since that post I've been running various NetBSD domUs in various
> versions of -current and this issue has not manifested, so I assume a
> recent change caused this?
> 
> Or maybe I fscked up somewhere. Feedback welcome :)
> 
> Hugo

Regards

Adam.