diff options
| author | Lu Baolu <baolu.lu@linux.intel.com> | 2020-09-27 14:24:28 +0800 |
|---|---|---|
| committer | Joerg Roedel <jroedel@suse.de> | 2020-10-01 14:54:17 +0200 |
| commit | 1a3f2fd7fc4e8f24510830e265de2ffb8e3300d2 (patch) | |
| tree | 1f23f0361f6d748e89e462440dfdf4c968522139 | |
| parent | 0bbe4ced53e36786eafc2ecbf9a1761f55b4a82e (diff) | |
| download | linux-1a3f2fd7fc4e8f24510830e265de2ffb8e3300d2.tar.gz | |
iommu/vt-d: Fix lockdep splat in iommu_flush_dev_iotlb()
Lock(&iommu->lock) without disabling irq causes lockdep warnings.
[ 12.703950] ========================================================
[ 12.703962] WARNING: possible irq lock inversion dependency detected
[ 12.703975] 5.9.0-rc6+ #659 Not tainted
[ 12.703983] --------------------------------------------------------
[ 12.703995] systemd-udevd/284 just changed the state of lock:
[ 12.704007] ffffffffbd6ff4d8 (device_domain_lock){..-.}-{2:2}, at:
iommu_flush_dev_iotlb.part.57+0x2e/0x90
[ 12.704031] but this lock took another, SOFTIRQ-unsafe lock in the past:
[ 12.704043] (&iommu->lock){+.+.}-{2:2}
[ 12.704045]
and interrupts could create inverse lock ordering between
them.
[ 12.704073]
other info that might help us debug this:
[ 12.704085] Possible interrupt unsafe locking scenario:
[ 12.704097] CPU0 CPU1
[ 12.704106] ---- ----
[ 12.704115] lock(&iommu->lock);
[ 12.704123] local_irq_disable();
[ 12.704134] lock(device_domain_lock);
[ 12.704146] lock(&iommu->lock);
[ 12.704158] <Interrupt>
[ 12.704164] lock(device_domain_lock);
[ 12.704174]
*** DEADLOCK ***
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20200927062428.13713-1-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
| -rw-r--r-- | drivers/iommu/intel/iommu.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index 87b17bac04c27c..2239c211178b66 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -2664,7 +2664,7 @@ static struct dmar_domain *dmar_insert_one_dev_info(struct intel_iommu *iommu, } /* Setup the PASID entry for requests without PASID: */ - spin_lock(&iommu->lock); + spin_lock_irqsave(&iommu->lock, flags); if (hw_pass_through && domain_type_is_si(domain)) ret = intel_pasid_setup_pass_through(iommu, domain, dev, PASID_RID2PASID); @@ -2674,7 +2674,7 @@ static struct dmar_domain *dmar_insert_one_dev_info(struct intel_iommu *iommu, else ret = intel_pasid_setup_second_level(iommu, domain, dev, PASID_RID2PASID); - spin_unlock(&iommu->lock); + spin_unlock_irqrestore(&iommu->lock, flags); if (ret) { dev_err(dev, "Setup RID2PASID failed\n"); dmar_remove_one_dev_info(dev); |