Messages in this thread | | | Subject | Re: [PATCH -next] iommu/dmar: silence RCU-list debugging warnings | From | Lu Baolu <> | Date | Sat, 7 Mar 2020 19:53:05 +0800 |
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Hi,
On 2020/3/6 4:15, Qian Cai wrote: > 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>
Thanks for the fix.
Acked-by: Lu Baolu <baolu.lu@linux.intel.com>
Best regards, baolu
> --- > 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 071bb42bbbc5..7b16c4db40b4 100644 > --- a/drivers/iommu/dmar.c > +++ b/drivers/iommu/dmar.c > @@ -363,7 +363,8 @@ static int dmar_pci_bus_notifier(struct notifier_block *nb, > { > 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 712be8bc6a7c..d7bf029df737 100644 > --- a/include/linux/dmar.h > +++ b/include/linux/dmar.h > @@ -74,11 +74,13 @@ struct dmar_pci_notify_info { > 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) \ >
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