iommu/vt-d: Silence RCU-list debugging warnings

BugLink: https://bugs.launchpad.net/bugs/1870142
[ Upstream commit f5152416528c2295f35dd9c9bd4fb27c4032413d ]

Similar to the commit 02d715b4a818 ("iommu/vt-d: Fix RCU list debugging
warnings"), there are several other places that call
list_for_each_entry_rcu() outside of an RCU read side critical section
but with dmar_global_lock held. Silence those false positives as well.

 drivers/iommu/intel-iommu.c:4288 RCU-list traversed in non-reader section!!
 1 lock held by swapper/0/1:
  #0: ffffffff935892c8 (dmar_global_lock){+.+.}, at: intel_iommu_init+0x1ad/0xb97

 drivers/iommu/dmar.c:366 RCU-list traversed in non-reader section!!
 1 lock held by swapper/0/1:
  #0: ffffffff935892c8 (dmar_global_lock){+.+.}, at: intel_iommu_init+0x125/0xb97

 drivers/iommu/intel-iommu.c:5057 RCU-list traversed in non-reader section!!
 1 lock held by swapper/0/1:
  #0: ffffffffa71892c8 (dmar_global_lock){++++}, at: intel_iommu_init+0x61a/0xb13

Signed-off-by: Qian Cai <cai@lca.pw>
Acked-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>

diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
index 6a9a1b987520fcbf7d308f4c07bde857ec9fb164..9e393b9c5091183199ee586700e0bebffa049f10 100644 (file)
--- a/drivers/iommu/dmar.c
+++ b/drivers/iommu/dmar.c
@@ -371,7 +371,8 @@ dmar_find_dmaru(struct acpi_dmar_hardware_unit *drhd)
 {
        struct dmar_drhd_unit *dmaru;
 
-       list_for_each_entry_rcu(dmaru, &dmar_drhd_units, list)
+       list_for_each_entry_rcu(dmaru, &dmar_drhd_units, list,
+                               dmar_rcu_check())
                if (dmaru->segment == drhd->segment &&
                    dmaru->reg_base_addr == drhd->address)
                        return dmaru;

diff --git a/include/linux/dmar.h b/include/linux/dmar.h
index d3ea390336f390517a859eb3e796bdcd9af68ad1..f397e52c2d9dedc96c9864a9d5940013aa719e0b 100644 (file)
--- a/include/linux/dmar.h
+++ b/include/linux/dmar.h
@@ -74,11 +74,13 @@ extern struct list_head dmar_drhd_units;
                                dmar_rcu_check())
 
 #define for_each_active_drhd_unit(drhd)                                        \
-       list_for_each_entry_rcu(drhd, &dmar_drhd_units, list)           \
+       list_for_each_entry_rcu(drhd, &dmar_drhd_units, list,           \
+                               dmar_rcu_check())                       \
                if (drhd->ignored) {} else
 
 #define for_each_active_iommu(i, drhd)                                 \
-       list_for_each_entry_rcu(drhd, &dmar_drhd_units, list)           \
+       list_for_each_entry_rcu(drhd, &dmar_drhd_units, list,           \
+                               dmar_rcu_check())                       \
                if (i=drhd->iommu, drhd->ignored) {} else
 
 #define for_each_iommu(i, drhd)                                                \