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Re: [Xen-devel] Creating a vm with a non-existent /dev/mapper/ tap2 devi

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Subject: Re: [Xen-devel] Creating a vm with a non-existent /dev/mapper/ tap2 device effectively hangs dom0 system
From: Nathan March <nathan@xxxxxx>
Date: Thu, 28 Jul 2011 15:13:00 -0700
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On 7/28/2011 12:00 PM, Nathan March wrote:
On 7/27/2011 4:29 PM, Nathan March wrote:
Have an interesting one here, originally found on xen 4.1.0 but just upgraded to xen 4.1.1 and it's still here.

Creating a VM with a tap2 device pointed at /dev/mapper/something, when that device doesn't exist, causes the tapdisk2 process to go into D mode and also manages to take out any process that queries it.

This also happens on proper shutdown of a VM, so I must have done something crazy to the setup here since other people haven't been complaining. If I start a VM, strace it's tapdisk2 and then send the VM a shutdown, the strace shows tapdisk2 hanging here:

*sigh*, for anyone who finds this via google, tracked it down to a stupid error. Shouldn't be using tapdisk2 for accessing an iscsi device since it appears as a raw block device, after changing to using phy: things work properly.

- Nathan

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