| Message ID | 20240329095133.576605-1-aaprelkov@usergate.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | iommu/arm-smmu-v3: Free MSIs in case of ENOMEM | expand |
On Fri, 29 Mar 2024 16:51:33 +0700 Aleksandr Aprelkov <aaprelkov@usergate.com> wrote: > If devm_add_action() returns ENOMEM, then MSIs allocated but > not freed on teardown. > > Found by Linux Verification Center (linuxtesting.org) with SVACE. > > Fixes: 166bdbd23161 ("iommu/arm-smmu: Add support for MSI on SMMUv3") > Signed-off-by: Aleksandr Aprelkov <aaprelkov@usergate.com> I've not checked this is an actual bug (though it looks like one from the context of the patch - the comment below is just about how you fix it. > --- > drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > 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 41f93c3ab160..136d0cdce6a9 100644 > --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c > +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c > @@ -3402,7 +3402,12 @@ static void arm_smmu_setup_msis(struct arm_smmu_device *smmu) > smmu->priq.q.irq = msi_get_virq(dev, PRIQ_MSI_INDEX); > > /* Add callback to free MSIs on teardown */ > - devm_add_action(dev, arm_smmu_free_msis, dev); > + ret = devm_add_action(dev, arm_smmu_free_msis, dev); Use devm_add_action_or_reset() which exists to solve the case of devm registration failing. > + if (ret) { > + dev_warn(dev, "failed to add free MSIs callback - falling back to wired irqs\n"); > + arm_smmu_free_msis(dev); > + return; > + } > } > > static void arm_smmu_setup_unique_irqs(struct arm_smmu_device *smmu)
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 41f93c3ab160..136d0cdce6a9 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c @@ -3402,7 +3402,12 @@ static void arm_smmu_setup_msis(struct arm_smmu_device *smmu) smmu->priq.q.irq = msi_get_virq(dev, PRIQ_MSI_INDEX); /* Add callback to free MSIs on teardown */ - devm_add_action(dev, arm_smmu_free_msis, dev); + ret = devm_add_action(dev, arm_smmu_free_msis, dev); + if (ret) { + dev_warn(dev, "failed to add free MSIs callback - falling back to wired irqs\n"); + arm_smmu_free_msis(dev); + return; + } } static void arm_smmu_setup_unique_irqs(struct arm_smmu_device *smmu)
If devm_add_action() returns ENOMEM, then MSIs allocated but not freed on teardown. Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: 166bdbd23161 ("iommu/arm-smmu: Add support for MSI on SMMUv3") Signed-off-by: Aleksandr Aprelkov <aaprelkov@usergate.com> --- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)