diff options
| author | Nicolin Chen <nicolinc@nvidia.com> | 2026-06-01 13:42:36 -0700 |
|---|---|---|
| committer | Jason Gunthorpe <jgg@nvidia.com> | 2026-06-05 11:07:12 -0300 |
| commit | 172fc8b19825a0f5884c38f2289188284e2d45ee (patch) | |
| tree | 138dffe367b14fc8f97dfe732efa4087dfe6f766 /drivers/iommu | |
| parent | 47916a54eeb2a9e654512ee609f71bd5b29db702 (diff) | |
iommufd: Break the loop on failure in iommufd_fault_fops_read()
On a copy_to_user() failure inside the inner list_for_each_entry, only the
inner loop breaks; the outer while re-fetches the just-restored fault group
and retries the failing copy_to_user() forever, spinning the reader at 100%
CPU with fault->mutex held.
Check rc after the inner loop and break the outer while as well.
Fixes: 07838f7fd529 ("iommufd: Add iommufd fault object")
Link: https://patch.msgid.link/r/336a9b6e44fe66a24199d3be777c405c85c98622.1780343944.git.nicolinc@nvidia.com
Cc: stable@vger.kernel.org
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Reviewed-by: Pranjal Shrivastava <praan@google.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Diffstat (limited to 'drivers/iommu')
| -rw-r--r-- | drivers/iommu/iommufd/eventq.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/iommu/iommufd/eventq.c b/drivers/iommu/iommufd/eventq.c index 613024ca8f1f..1c010e691f97 100644 --- a/drivers/iommu/iommufd/eventq.c +++ b/drivers/iommu/iommufd/eventq.c @@ -168,6 +168,8 @@ static ssize_t iommufd_fault_fops_read(struct file *filep, char __user *buf, } done += fault_size; } + if (rc) + break; } mutex_unlock(&fault->mutex); |