RE: [PATCH 2/2] iommu/msm: wire up fault handling

["Sricharan" <sricharan-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org>]

Hi,

>When things go wrong on the gpu, we can get *thousands* of faults.  With
>so many pr_err() prints, which were slowing down resuming the iommu,
>drm/msm would think the GPU had actually hung and reset it.
>
>Wire up the fault reporting, so instead we get a small ratelimited print
>of the fault address from drm/msm's fault handler instead.
>
>Signed-off-by: Rob Clark <robdclark-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
>---
> drivers/iommu/msm_iommu.c | 16 +++++++++++-----
> drivers/iommu/msm_iommu.h |  3 +++
> 2 files changed, 14 insertions(+), 5 deletions(-)
>
>diff --git a/drivers/iommu/msm_iommu.c b/drivers/iommu/msm_iommu.c
>index f6f596f..1110b72 100644
>--- a/drivers/iommu/msm_iommu.c
>+++ b/drivers/iommu/msm_iommu.c
>@@ -411,6 +411,7 @@ static int msm_iommu_attach_dev(struct iommu_domain *domain, struct device *dev)
> 			}
> 			__disable_clocks(iommu);
> 			list_add(&iommu->dom_node, &priv->list_attached);
>+			iommu->domain = domain;
> 		}
> 	}
>
>@@ -614,8 +615,8 @@ irqreturn_t msm_iommu_fault_handler(int irq, void *dev_id)
> 		goto fail;
> 	}
>
>-	pr_err("Unexpected IOMMU page fault!\n");
>-	pr_err("base = %08x\n", (unsigned int)iommu->base);
>+	pr_debug("Unexpected IOMMU page fault!\n");

              So was just thinking if its better to have only this as a ratelimited print,
              for global faults ?, otherwise
                Reviewed-by: sricharan-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org
 
Regards,
 Sricharan