Re: [PATCH v2] iommu/tegra241-cmdqv: do not use smp_processor_id in preemptible context

From: Will Deacon
Date: Mon Dec 09 2024 - 19:18:30 EST


On Fri, 06 Dec 2024 10:01:14 -0300, Luis Claudio R. Goncalves wrote:
> During boot some of the calls to tegra241_cmdqv_get_cmdq() will happen
> in preemptible context. As this function calls smp_processor_id(), if
> CONFIG_DEBUG_PREEMPT is enabled, these calls will trigger a series of
> "BUG: using smp_processor_id() in preemptible" backtraces.
>
> As tegra241_cmdqv_get_cmdq() only calls smp_processor_id() to use the
> CPU number as a factor to balance out traffic on cmdq usage, it is safe
> to use raw_smp_processor_id() here.
>
> [...]

Applied to will (for-joerg/arm-smmu/fixes), thanks!

[1/1] iommu/tegra241-cmdqv: do not use smp_processor_id in preemptible context
https://git.kernel.org/will/c/1f806218164d

Cheers,
--
Will

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