lkml.org 
[lkml]   [2020]   [Mar]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH AUTOSEL 5.4 51/73] iommu/vt-d: Silence RCU-list debugging warnings
Date
From: Qian Cai <cai@lca.pw>

[ 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>
---
drivers/iommu/dmar.c | 3 ++-
include/linux/dmar.h | 6 ++++--
2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
index 7196cabafb252..6ec5da4d028f9 100644
--- a/drivers/iommu/dmar.c
+++ b/drivers/iommu/dmar.c
@@ -363,7 +363,8 @@ 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 a7cf3599d9a1c..e0d52e9358c9c 100644
--- a/include/linux/dmar.h
+++ b/include/linux/dmar.h
@@ -73,11 +73,13 @@ extern struct list_head dmar_drhd_units;
list_for_each_entry_rcu(drhd, &dmar_drhd_units, list)

#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) \
--
2.20.1
\
 
 \ /
  Last update: 2020-03-18 22:07    [W:0.214 / U:30.936 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site