WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

Re: [Xen-devel] RE: Crashdump and IOMMU problems

At 23:11 +0100 on 11 May (1305155493), Kay, Allen M wrote:
> I believe Jan was involved with adding kexec support in iommu code.
> 
> As for systematic way to disable active DMA, isn't this similar to OS 
> shutdown case when all the drivers are unloaded?  Does kexec unload all of 
> the device drivers?  Once all the drivers are unloaded, there shouldn't be 
> any DMA transactions going on.
> 
> I don't know much about kexec flow but it sound like the high level flow is: 
> 1) dom0 kernel shutdown all of the device dirver and then 2) call 
> iommu_ops->suspend() or crash_shutdown() to disable all of the iommu hardware.
> 

In Xen we might have to kexec on crash without knowing even which VM is
driving the devices, so we can't do a clean unload.  It might be
worthwhile just walking the PCI busses disabling everything, though. 

Tim.

-- 
Tim Deegan <Tim.Deegan@xxxxxxxxxx>
Principal Software Engineer, Xen Platform Team
Citrix Systems UK Ltd.  (Company #02937203, SL9 0BG)

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel

<Prev in Thread] Current Thread [Next in Thread>