[PATCH v6 14/21] iommu/tegra: gart: Fix spinlock recursion
From: Dmitry Osipenko <digetx@gmail.com>
Date: 2018-12-09 20:32:10
Also in:
linux-iommu, linux-tegra, lkml
Subsystem:
iommu subsystem, tegra iommu drivers, the rest · Maintainers:
Joerg Roedel, Will Deacon, Thierry Reding, Linus Torvalds
Fix spinlock recursion bug that happens on IOMMU domain destruction if any of the allocated domains have devices attached to them. Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Acked-by: Thierry Reding <redacted> --- drivers/iommu/tegra-gart.c | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-)
diff --git a/drivers/iommu/tegra-gart.c b/drivers/iommu/tegra-gart.c
index 0a72b6afa842..d4a642c636f1 100644
--- a/drivers/iommu/tegra-gart.c
+++ b/drivers/iommu/tegra-gart.c@@ -197,25 +197,33 @@ static int gart_iommu_attach_dev(struct iommu_domain *domain, return err; } -static void gart_iommu_detach_dev(struct iommu_domain *domain, - struct device *dev) +static void __gart_iommu_detach_dev(struct iommu_domain *domain, + struct device *dev) { struct gart_domain *gart_domain = to_gart_domain(domain); struct gart_device *gart = gart_domain->gart; struct gart_client *c; - spin_lock(&gart->client_lock); - list_for_each_entry(c, &gart->client, list) { if (c->dev == dev) { list_del(&c->list); devm_kfree(gart->dev, c); dev_dbg(gart->dev, "Detached %s\n", dev_name(dev)); - goto out; + return; } } - dev_err(gart->dev, "Couldn't find\n"); -out: + + dev_err(gart->dev, "Couldn't find %s to detach\n", dev_name(dev)); +} + +static void gart_iommu_detach_dev(struct iommu_domain *domain, + struct device *dev) +{ + struct gart_domain *gart_domain = to_gart_domain(domain); + struct gart_device *gart = gart_domain->gart; + + spin_lock(&gart->client_lock); + __gart_iommu_detach_dev(domain, dev); spin_unlock(&gart->client_lock); }
@@ -255,7 +263,7 @@ static void gart_iommu_domain_free(struct iommu_domain *domain) struct gart_client *c; list_for_each_entry(c, &gart->client, list) - gart_iommu_detach_dev(domain, c->dev); + __gart_iommu_detach_dev(domain, c->dev); } spin_unlock(&gart->client_lock); }
--
2.19.1