diff options
| author | Jason Gunthorpe <jgg@nvidia.com> | 2024-12-05 20:13:41 -0400 |
|---|---|---|
| committer | Joerg Roedel <jroedel@suse.de> | 2024-12-10 10:12:05 +0100 |
| commit | 4a552f7890f0870f6d9fd4fbc6c05cea7bfd4503 (patch) | |
| tree | 3ed54b9d4af1e61f82ed5e421cd8c6ad1b87e9a7 | |
| parent | fac04efc5c793dccbd07e2d59af9f90b7fc0dca4 (diff) | |
iommu/amd: Put list_add/del(dev_data) back under the domain->lock
The list domain->dev_list is protected by the domain->lock spinlock.
Any iteration, addition or removal must be under the lock.
Move the list_del() up into the critical section. pdom_is_sva_capable(),
and destroy_gcr3_table() do not interact with the list element.
Wrap the list_add() in a lock, it would make more sense if this was under
the same critical section as adjusting the refcounts earlier, but that
requires more complications.
Fixes: d6b47dec3684 ("iommu/amd: Reduce domain lock scope in attach device path")
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Vasant Hegde <vasant.hegde@amd.com>
Link: https://lore.kernel.org/r/1-v1-3b9edcf8067d+3975-amd_dev_list_locking_jgg@nvidia.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
| -rw-r--r-- | drivers/iommu/amd/iommu.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c index 3f691e1fd22c..23a168e229b1 100644 --- a/drivers/iommu/amd/iommu.c +++ b/drivers/iommu/amd/iommu.c @@ -2073,6 +2073,7 @@ static int attach_device(struct device *dev, struct iommu_dev_data *dev_data = dev_iommu_priv_get(dev); struct amd_iommu *iommu = get_amd_iommu_from_dev_data(dev_data); struct pci_dev *pdev; + unsigned long flags; int ret = 0; mutex_lock(&dev_data->mutex); @@ -2113,7 +2114,9 @@ static int attach_device(struct device *dev, /* Update data structures */ dev_data->domain = domain; + spin_lock_irqsave(&domain->lock, flags); list_add(&dev_data->list, &domain->dev_list); + spin_unlock_irqrestore(&domain->lock, flags); /* Update device table */ dev_update_dte(dev_data, true); @@ -2160,6 +2163,7 @@ static void detach_device(struct device *dev) /* Flush IOTLB and wait for the flushes to finish */ spin_lock_irqsave(&domain->lock, flags); amd_iommu_domain_flush_all(domain); + list_del(&dev_data->list); spin_unlock_irqrestore(&domain->lock, flags); /* Clear GCR3 table */ @@ -2168,7 +2172,6 @@ static void detach_device(struct device *dev) /* Update data structures */ dev_data->domain = NULL; - list_del(&dev_data->list); /* decrease reference counters - needs to happen after the flushes */ pdom_detach_iommu(iommu, domain); |