[Qemu-devel] Re: commit e09a5267

[Anthony Liguori <anthony@codemonkey.ws>]

Jan Kiszka wrote:
> Avi Kivity wrote:
>   
>> On 09/10/2009 04:56 PM, Anthony Liguori wrote:
>>     
>>> The problem is patch volume.  We often see hundreds of patches a day. 
>>> If typing a mail for each patch takes 2 minutes, that's potentially
>>> hours spent just on sending these mails.
>>>
>>>       
>> You exaggerate.  The average rate is 13 patches per calendar day.  The
>> bulk of the patches are in patchsets which can be acked as a set, not
>> once per patch.
>>
>>     
>>> What I really need is some way to automatically generate these
>>> notifications.  It's pretty easy to send a mail when a patch enters
>>> the queue but it's more difficult to send a mail when a patch is
>>> removed from the queue via a rebase.  Often times, I remove patches
>>> from the queue simply because I'm not the right path for the patches
>>> to be committed from (like linux-user).
>>>       
>> I think more per-patch attention is needed, not less, for example see
>> this commit:
>>
>> commit e09a5267adf0af25b55d2abaf06e288b2d9537ea
>> Author: Dustin Kirkland <kirkland@canonical.com>
>> Date:   Thu Sep 3 12:31:33 2009 -0500
>>
>>     qemu-kvm: fix segfault when running kvm without /dev/kvm, falling
>> back to non-accelerated mode
>>
>>     qemu-kvm: fix segfault when running kvm without /dev/kvm, falling back
>>     to non-accelerated mode
>>
>>     We're seeing segfaults on systems without access to /dev/kvm.  It
>>     looks like the global kvm_allowed is being set just a little too late
>>     in vl.c.  This patch moves the kvm initialization a bit higher in the
>>     vl.c main, just after options processing, and solves the segfaults.
>>     We're carrying this patch in Ubuntu 9.10 Alpha.  Please apply
>>     upstream, or advise if and why this might not be the optimal solution.
>>
>>     Signed-off-by: Dustin Kirkland <kirkland@canonical.com>
>>
>>     Move the kvm_init() call a bit higher to fix a segfault when
>>     /dev/kvm is not available.  The kvm_allowed global needs
>>     to be set correctly a little earlier.
>>
>>     Signed-off-by: Dustin Kirkland <kirkland@canonical.com>
>>     Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
>>
>> There are many examples like this in the tree which is a pity.  Others
>> include parts of an email conversation.  I'd like history to look better
>> than this.
>>     
>
> Even worse, I think this patch does not belong into upstream as it fixed
> a qemu-kvm-only bug. I think this was caused by Dustin CC'ing qemu, right?
>
> Did anyone test properly if the change has no side effects on upstream
> kvm (which has a different initialization scheme)?
>   

It doesn't break upstream qemu's -enable-kvm.

Regards,

Anthony Liguori