Re: [PATCH v3] iommu/arm-smmu-v3: Shrink command/event/PRI queues in kdump kernel

Nicolin Chen <[email protected]> Tue, 4 Aug 2026 09:04:32 -0700
Newsgroups dev.linux.lists.iommu,org.infradead.lists.linux-arm-kernel,org.kernel.vger.linux-kernel
Message-ID <[email protected]>
On Tue, Aug 04, 2026 at 11:17:04AM -0300, Jason Gunthorpe wrote:
> On Tue, Aug 04, 2026 at 03:02:46PM +0100, Will Deacon wrote:
> > > Would skipping their allocation when is_kdump_kernel() be acceptable on
> > > its own, or would you rather see it done differently?
> > 
> > With Nicolin's patch, we can just avoid allocating the priq and the evtq
> > entirely in the kdump case. We can then add a cmdline option to control
> > the maximum size of the cmdq, which is useful regardless of kdump.
> 
> I would still prefer kdump do this re-sizing automatically, even if we
> do add a commandline. It makes it easire to deploy than having to know
> secret command lines :\
> 
> So functionally I still think this patch is fine, though yes it points
> out more things in Nicolin's work too.

I will send a v10 of mine, to skip the EVTQ/PRIQ allocations.

Thanks
Nicolin