diff options
author | Lu Baolu <baolu.lu@linux.intel.com> | 2020-09-27 09:24:28 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-10-14 12:55:51 +0300 |
commit | 954adf70118902179e284934f234067a2a965426 (patch) | |
tree | 63084a22c2eff5cb88ce1da161d04e9cab55982f /drivers/iommu | |
parent | 31bc10ac6d01902586fb3c6535e46bb899bc7b5f (diff) | |
download | linux-954adf70118902179e284934f234067a2a965426.tar.xz |
iommu/vt-d: Fix lockdep splat in iommu_flush_dev_iotlb()
[ Upstream commit 1a3f2fd7fc4e8f24510830e265de2ffb8e3300d2 ]
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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/iommu')
-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 fbe0b0cc56ed..24a84d294fd0 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -2617,7 +2617,7 @@ 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); @@ -2627,7 +2627,7 @@ 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); |