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

Jason Gunthorpe <[email protected]> Thu, 6 Aug 2026 12:58:55 -0300
Newsgroups dev.linux.lists.iommu,org.infradead.lists.linux-arm-kernel,org.kernel.vger.linux-kernel
Message-ID <[email protected]>
On Thu, Aug 06, 2026 at 02:00:28PM +0100, Will Deacon wrote:

> I probably wouldn't make a size of 0 disable the queue, either. Have a
> minimum size of a page or something like that.

If there is an argument someone is pressed for memory on cmdq they
probably also want to disable the fault queue (and fault support
entirely) and shrink the event queue too.

The kdump case was an obvious one, but I imagine an embedded system
may want similar tuning.

The non-disable-able ones should min to page size..

Jason