From: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Date: Fri, 26 Nov 2021 21:55:55 +0800
Subject: iommu/vt-d: Fix an unbalanced rcu_read_lock/rcu_read_unlock()
Git-commit: 4e5973dd2725bb30c3db622f7d73f7a5864ce718
Patch-mainline: v5.16-rc3
References: bsc#1205701
If we return -EOPNOTSUPP, the rcu lock remains lock. This is spurious.
Go through the end of the function instead. This way, the missing
'rcu_read_unlock()' is called.
Fixes: 7afd7f6aa21a ("iommu/vt-d: Check FL and SL capability sanity in scalable mode")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/40cc077ca5f543614eab2a10e84d29dd190273f6.1636217517.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20211126135556.397932-2-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
drivers/iommu/intel/cap_audit.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/iommu/intel/cap_audit.c b/drivers/iommu/intel/cap_audit.c
index b39d223926a4..71596fc62822 100644
--- a/drivers/iommu/intel/cap_audit.c
+++ b/drivers/iommu/intel/cap_audit.c
@@ -144,6 +144,7 @@ static int cap_audit_static(struct intel_iommu *iommu, enum cap_audit_type type)
{
struct dmar_drhd_unit *d;
struct intel_iommu *i;
+ int rc = 0;
rcu_read_lock();
if (list_empty(&dmar_drhd_units))
@@ -169,11 +170,11 @@ static int cap_audit_static(struct intel_iommu *iommu, enum cap_audit_type type)
*/
if (intel_cap_smts_sanity() &&
!intel_cap_flts_sanity() && !intel_cap_slts_sanity())
- return -EOPNOTSUPP;
+ rc = -EOPNOTSUPP;
out:
rcu_read_unlock();
- return 0;
+ return rc;
}
int intel_cap_audit(enum cap_audit_type type, struct intel_iommu *iommu)