[PATCH v1 5/6] iommu: Do not revert set_domain for the last gdev
From: Nicolin Chen <hidden>
Date: 2025-10-12 23:58:17
Also in:
asahi, linux-arm-msm, linux-iommu, linux-mediatek, linux-patches, linux-riscv, linux-rockchip, linux-s390, linux-samsung-soc, linux-sunxi, linux-tegra, lkml, virtualization
Subsystem:
iommu subsystem, the rest · Maintainers:
Joerg Roedel, Will Deacon, Linus Torvalds
The last gdev is the device that failed the __iommu_device_set_domain(). So, it doesn't need to be reverted, given it's attached to group->domain already. This is not a problem currently, since it's a simply re-attach. However, the core will need to pass in the old domain to __iommu_device_set_domain so the old domain pointers would be inconsistent between a failed device and all its prior succeeded devices, as all the prior devices need to be reverted. Avoid the re-attach for the last gdev, by breaking before the revert. Signed-off-by: Nicolin Chen <redacted> --- drivers/iommu/iommu.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index adef1a37f9311..ce141f095f969 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c@@ -2403,6 +2403,9 @@ static int __iommu_group_set_domain_internal(struct iommu_group *group, */ last_gdev = gdev; for_each_group_device(group, gdev) { + /* No need to revert the last gdev that failed to set domain */ + if (gdev == last_gdev) + break; /* * A NULL domain can happen only for first probe, in which case * we leave group->domain as NULL and let release clean
@@ -2412,8 +2415,6 @@ static int __iommu_group_set_domain_internal(struct iommu_group *group, WARN_ON(__iommu_device_set_domain( group, gdev->dev, group->domain, IOMMU_SET_DOMAIN_MUST_SUCCEED)); - if (gdev == last_gdev) - break; } return ret; }
--
2.43.0