| Message ID | 0812e9f61234cbcdc5cab7de307e1c9a8e3c9498.1731422868.git.robin.murphy@arm.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | iommu/arm-smmu: Minor probe_device related improvements | expand |
On Tue, Nov 12, 2024 at 02:49:59PM +0000, Robin Murphy wrote: > If SMMU probe fails afer arm_smmu_device_reset(), we leave the SMMU > enabled with an empty Stream Table, silently blocking all DMA. This > proves rather annoying for debugging said probe failure, so let's handle > it a bit better by putting the SMMU back into (more or less) the same > state as if it hadn't probed at all. > > Signed-off-by: Robin Murphy <robin.murphy@arm.com> > --- > drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c > index 7908fca962fe..566d66e9c91e 100644 > --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c > +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c > @@ -4640,6 +4640,7 @@ static int arm_smmu_device_probe(struct platform_device *pdev) > iommu_device_sysfs_remove(&smmu->iommu); > free_iopf: > iopf_queue_free(smmu->evtq.iopf); > + arm_smmu_device_disable(smmu); > return ret; > } Heh, this is starting to look an awful lot like arm_smmu_device_remove()... Will
On 12/11/2024 3:57 pm, Will Deacon wrote: > On Tue, Nov 12, 2024 at 02:49:59PM +0000, Robin Murphy wrote: >> If SMMU probe fails afer arm_smmu_device_reset(), we leave the SMMU >> enabled with an empty Stream Table, silently blocking all DMA. This >> proves rather annoying for debugging said probe failure, so let's handle >> it a bit better by putting the SMMU back into (more or less) the same >> state as if it hadn't probed at all. >> >> Signed-off-by: Robin Murphy <robin.murphy@arm.com> >> --- >> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 1 + >> 1 file changed, 1 insertion(+) >> >> diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c >> index 7908fca962fe..566d66e9c91e 100644 >> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c >> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c >> @@ -4640,6 +4640,7 @@ static int arm_smmu_device_probe(struct platform_device *pdev) >> iommu_device_sysfs_remove(&smmu->iommu); >> free_iopf: >> iopf_queue_free(smmu->evtq.iopf); >> + arm_smmu_device_disable(smmu); >> return ret; >> } > > Heh, this is starting to look an awful lot like arm_smmu_device_remove()... Indeed, functionally that's rather the point; implementation-wise, you know I'd branch straight into the middle of a different function if the language let me :) Robin.
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c index 7908fca962fe..566d66e9c91e 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c @@ -4640,6 +4640,7 @@ static int arm_smmu_device_probe(struct platform_device *pdev) iommu_device_sysfs_remove(&smmu->iommu); free_iopf: iopf_queue_free(smmu->evtq.iopf); + arm_smmu_device_disable(smmu); return ret; }
If SMMU probe fails afer arm_smmu_device_reset(), we leave the SMMU enabled with an empty Stream Table, silently blocking all DMA. This proves rather annoying for debugging said probe failure, so let's handle it a bit better by putting the SMMU back into (more or less) the same state as if it hadn't probed at all. Signed-off-by: Robin Murphy <robin.murphy@arm.com> --- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 1 + 1 file changed, 1 insertion(+)