[PATCH 5.12 595/700] iommu/dma: Fix IOVA reserve dma ranges

From: Greg Kroah-Hartman
Date: Mon Jul 12 2021 - 04:04:52 EST


From: Srinath Mannam <srinath.mannam@xxxxxxxxxxxx>

[ Upstream commit 571f316074a203e979ea90211d9acf423dfe5f46 ]

Fix IOVA reserve failure in the case when address of first memory region
listed in dma-ranges is equal to 0x0.

Fixes: aadad097cd46f ("iommu/dma: Reserve IOVA for PCIe inaccessible DMA address")
Signed-off-by: Srinath Mannam <srinath.mannam@xxxxxxxxxxxx>
Reviewed-by: Robin Murphy <robin.murphy@xxxxxxx>
Tested-by: Sven Peter <sven@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20200914072319.6091-1-srinath.mannam@xxxxxxxxxxxx
Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/iommu/dma-iommu.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index fdd095e1fa52..5f75ab0dfc73 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -252,9 +252,11 @@ resv_iova:
lo = iova_pfn(iovad, start);
hi = iova_pfn(iovad, end);
reserve_iova(iovad, lo, hi);
- } else {
+ } else if (end < start) {
/* dma_ranges list should be sorted */
- dev_err(&dev->dev, "Failed to reserve IOVA\n");
+ dev_err(&dev->dev,
+ "Failed to reserve IOVA [%#010llx-%#010llx]\n",
+ start, end);
return -EINVAL;
}

--
2.30.2