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Re: [PATCH] iommu/amd: Use raw_cpu_ptr() instead of get_cpu_ptr() for ->flush_queue

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Hi Sebastian,

On Wed, Sep 06, 2017 at 12:34:59PM +0200, Sebastian Andrzej Siewior wrote:
> get_cpu_ptr() disables preemption and returns the ->flush_queue object
> of the current CPU. raw_cpu_ptr() does the same except that it not
> disable preemption which means the scheduler can move it to another CPU
> after it obtained the per-CPU object.
> In this case this is not bad because the data structure itself is
> protected with a spin_lock. This change shouldn't matter in general
> but on RT it does because the sleeping lock can't be accessed with
> disabled preemption.

I moved the flushing to driver/iommu/iova.c to share it with the Intel
IOMMU and possibly other drivers too, so this patch does no longer apply
to v4.14-rc1. Can you update the patch to these changes?

Regards,

	Joerg

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Re: [PATCH] iommu/amd: Use raw_cpu_ptr() instead of get_cpu_ptr()  for ->flush_queue Joerg Roedel <joro@8bytes.org> - 2017-09-19 11:50 +0200
  [PATCH v2] iommu/iova: Use raw_cpu_ptr() instead of get_cpu_ptr()  for ->fq Sebastian Andrzej Siewior <bigeasy@linutronix.de> - 2017-09-21 17:30 +0200

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