linux-kernel - Re: [PATCH v4 1/2] iommu/arm-smmu-v3: Fix CMDQ timeout warning

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20251201094244.00002463@linux.microsoft.com>
Date: Mon, 1 Dec 2025 09:42:44 -0800
From: Jacob Pan <jacob.pan@...ux.microsoft.com>
To: Will Deacon <will@...nel.org>
Cc: linux-kernel@...r.kernel.org, "iommu@...ts.linux.dev"
 <iommu@...ts.linux.dev>, Joerg Roedel <joro@...tes.org>, Mostafa Saleh
 <smostafa@...gle.com>, Jason Gunthorpe <jgg@...dia.com>, Robin Murphy
 <robin.murphy@....com>, Nicolin Chen <nicolinc@...dia.com>, Zhang Yu
 <zhangyu1@...ux.microsoft.com>, Jean Philippe-Brucker
 <jean-philippe@...aro.org>, Alexander Grest <Alexander.Grest@...rosoft.com>
Subject: Re: [PATCH v4 1/2] iommu/arm-smmu-v3: Fix CMDQ timeout warning

Hi Will,

On Tue, 25 Nov 2025 17:19:16 +0000
Will Deacon <will@...nel.org> wrote:

> I'm assuming you're seeing problems with an emulated command queue?
> Any chance you could make that bigger?
Yes, it was initially observed on HyperV emulated CMDQ with small queue
size, which was chosen for latency reasons.

But as I explained in the other thread, the queue space polling timeout
detection problem is not directly related to queue size. It is a
code logic bug IMHO.

Sorry I forgot to directly answer these.