[PATCH v7 01/28] iommufd: Report unmapped bytes in the error path of iopt_unmap_iova_range
From: Nicolin Chen <hidden>
Date: 2025-06-26 19:35:22
Also in:
linux-doc, linux-iommu, linux-kselftest, linux-patches, linux-tegra, lkml
Subsystem:
iommu subsystem, iommufd, the rest · Maintainers:
Joerg Roedel, Will Deacon, Jason Gunthorpe, Kevin Tian, Linus Torvalds
There are callers that read the unmapped bytes even when rc != 0. Thus, do
not forget to report it in the error path too.
Fixes: 8d40205f6093 ("iommufd: Add kAPI toward external drivers for kernel access")
Cc: stable@vger.kernel.org
Signed-off-by: Nicolin Chen <redacted>
---
drivers/iommu/iommufd/io_pagetable.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/iommu/iommufd/io_pagetable.c b/drivers/iommu/iommufd/io_pagetable.c
index 13d010f19ed1..22fc3a12109f 100644
--- a/drivers/iommu/iommufd/io_pagetable.c
+++ b/drivers/iommu/iommufd/io_pagetable.c@@ -743,8 +743,10 @@ static int iopt_unmap_iova_range(struct io_pagetable *iopt, unsigned long start, iommufd_access_notify_unmap(iopt, area_first, length); /* Something is not responding to unmap requests. */ tries++; - if (WARN_ON(tries > 100)) - return -EDEADLOCK; + if (WARN_ON(tries > 100)) { + rc = -EDEADLOCK; + goto out_unmapped; + } goto again; }
@@ -766,6 +768,7 @@ static int iopt_unmap_iova_range(struct io_pagetable *iopt, unsigned long start, out_unlock_iova: up_write(&iopt->iova_rwsem); up_read(&iopt->domains_rwsem); +out_unmapped: if (unmapped) *unmapped = unmapped_bytes; return rc;
--
2.43.0