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Re: [PATCH 2/2] amd/iommu: Remove dead non-atomic update checking

To: Jan Beulich <jbeulich@xxxxxxxx>, Teddy Astie <teddy.astie@xxxxxxxxxx>

From: Jason Andryuk <jason.andryuk@xxxxxxx>

Date: Fri, 14 Nov 2025 15:45:48 -0500

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Cc: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>, Roger Pau Monné <roger.pau@xxxxxxxxxx>, <xen-devel@xxxxxxxxxxxxxxxxxxxx>

Delivery-date: Fri, 14 Nov 2025 22:04:07 +0000

List-id: Xen developer discussion <xen-devel.lists.xenproject.org>

On 2025-11-13 06:37, Jan Beulich wrote:

On 12.11.2025 16:37, Teddy Astie wrote:

When updating a DTE, amd_iommu_setup_domain_device() would check if
the update had been non-atomic (i.e rc > 0) and throw a warning if
such non-atomic update could be dangerous.  However since commit
3fc44151d83d, rc can no longer be positive, making this branch
unreachable code.


I.e. it addresses a Misra concern and hence ...

No functional change intended.

Signed-off-by: Teddy Astie <teddy.astie@xxxxxxxxxx>


... wants at least an Amends: tag, likely a Fixes: one. Then:
Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>

Reviewed-by: Jason Andryuk <jason.andryuk@xxxxxxx>

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