| Message ID | 1502182681-8966-1-git-send-email-asavkov@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Artem, Thanks for the patch. On Tue, Aug 08, 2017 at 10:58:01AM +0200, Artem Savkov wrote: > Commit c54451a "iommu/arm-smmu: Fix the error path in arm_smmu_add_device" > removed fwspec assignment in legacy_binding path as redundant which is > wrong. It needs to be updated after fwspec initialisation in > arm_smmu_register_legacy_master() as it is dereferenced later. Without > this there is a NULL-pointer dereference panic during boot on some hosts. > > Signed-off-by: Artem Savkov <asavkov@redhat.com> > --- > drivers/iommu/arm-smmu.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c > index b97188a..95f1c86 100644 > --- a/drivers/iommu/arm-smmu.c > +++ b/drivers/iommu/arm-smmu.c > @@ -1519,6 +1519,7 @@ static int arm_smmu_add_device(struct device *dev) > > if (using_legacy_binding) { > ret = arm_smmu_register_legacy_master(dev, &smmu); > + fwspec = dev->iommu_fwspec; > if (ret) > goto out_free; > } else if (fwspec && fwspec->ops == &arm_smmu_ops) { Damn, you're completely right! Robin and I bashed our heads against this for a while and couldn't remember why the code was structured like it was, but that explains it. Can you add a comment saying that arm_smmu_register_legacy_master will allocate an fwspec if its initially NULL, please? Cheers, Will
diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c index b97188a..95f1c86 100644 --- a/drivers/iommu/arm-smmu.c +++ b/drivers/iommu/arm-smmu.c @@ -1519,6 +1519,7 @@ static int arm_smmu_add_device(struct device *dev) if (using_legacy_binding) { ret = arm_smmu_register_legacy_master(dev, &smmu); + fwspec = dev->iommu_fwspec; if (ret) goto out_free; } else if (fwspec && fwspec->ops == &arm_smmu_ops) {
Commit c54451a "iommu/arm-smmu: Fix the error path in arm_smmu_add_device" removed fwspec assignment in legacy_binding path as redundant which is wrong. It needs to be updated after fwspec initialisation in arm_smmu_register_legacy_master() as it is dereferenced later. Without this there is a NULL-pointer dereference panic during boot on some hosts. Signed-off-by: Artem Savkov <asavkov@redhat.com> --- drivers/iommu/arm-smmu.c | 1 + 1 file changed, 1 insertion(+)