diff mbox series

[RFC,V2,25/37] mm, x86, dmem: fix estimation of reserved page for vaddr_get_pfn()

Message ID 3bd3e2d485c46fae9eaeb501e1a6c51d19570b49.1607332046.git.yuleixzhang@tencent.com (mailing list archive)
State New, archived
Headers show
Series Enhance memory utilization with DMEMFS | expand

Commit Message

yulei zhang Dec. 7, 2020, 11:31 a.m. UTC 
From: Yulei Zhang <yuleixzhang@tencent.com>

Fix estimation of reserved page for vaddr_get_pfn() and
check 'ret' before checking writable permission

Signed-off-by: Chen Zhuo <sagazchen@tencent.com>
Signed-off-by: Yulei Zhang <yuleixzhang@tencent.com>
---
 drivers/vfio/vfio_iommu_type1.c | 4 ++++
 1 file changed, 4 insertions(+)
diff mbox series

Patch

diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 67e8276..c465d1a 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -471,6 +471,10 @@  static int vaddr_get_pfn(struct mm_struct *mm, unsigned long vaddr,
 		if (ret == -EAGAIN)
 			goto retry;
 
+		if (!ret && (prot & IOMMU_WRITE) &&
+		    !(vma->vm_flags & VM_WRITE))
+			ret = -EFAULT;
+
 		if (!ret && !is_invalid_reserved_pfn(*pfn))
 			ret = -EFAULT;
 	}