From: Jason Gunthorpe Date: Mon, 13 Feb 2023 18:02:42 +0000 (-0400) Subject: iommufd: Do not add the same hwpt to the ioas->hwpt_list twice X-Git-Tag: v6.2.3~18 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=c44adefdcf472f946f0632f4e0ddcbf3e00b8516;p=thirdparty%2Fkernel%2Fstable.git iommufd: Do not add the same hwpt to the ioas->hwpt_list twice commit b4ff830eca097df51af10a9be29e8cc817327919 upstream. The hwpt is added to the hwpt_list only during its creation, it is never added again. This hunk is some missed leftover from rework. Adding it twice will corrupt the linked list in some cases. It effects HWPT specific attachment, which is something the test suite cannot cover until we can create a legitimate struct device with a non-system iommu "driver" (ie we need the bus removed from the iommu code) Cc: stable@vger.kernel.org Fixes: e8d57210035b ("iommufd: Add kAPI toward external drivers for physical devices") Link: https://lore.kernel.org/r/1-v1-4336b5cb2fe4+1d7-iommufd_hwpt_jgg@nvidia.com Reviewed-by: Kevin Tian Reported-by: Kevin Tian Signed-off-by: Jason Gunthorpe Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/iommu/iommufd/device.c b/drivers/iommu/iommufd/device.c index d81f93a321afc..f6f42d8bc8ad8 100644 --- a/drivers/iommu/iommufd/device.c +++ b/drivers/iommu/iommufd/device.c @@ -346,10 +346,6 @@ int iommufd_device_attach(struct iommufd_device *idev, u32 *pt_id) rc = iommufd_device_do_attach(idev, hwpt); if (rc) goto out_put_pt_obj; - - mutex_lock(&hwpt->ioas->mutex); - list_add_tail(&hwpt->hwpt_item, &hwpt->ioas->hwpt_list); - mutex_unlock(&hwpt->ioas->mutex); break; } case IOMMUFD_OBJ_IOAS: {