[PATCH v4 22/24] iommu: Only log strictness for DMA domains

From: Robin Murphy
Date: Wed Aug 11 2021 - 08:23:12 EST


When passthrough is enabled, the default strictness policy becomes
irrelevant, since any subsequent runtime override to a DMA domain type
now embodies an explicit choice of strictness as well. Save on noise by
only logging the default policy when it is meaningfully in effect.

Reviewed-by: John Garry <john.garry@xxxxxxxxxx>
Reviewed-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
Signed-off-by: Robin Murphy <robin.murphy@xxxxxxx>
---
drivers/iommu/iommu.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index b141161d5bbc..63face36fc49 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -144,10 +144,11 @@ static int __init iommu_subsys_init(void)
(iommu_cmd_line & IOMMU_CMD_LINE_DMA_API) ?
"(set via kernel command line)" : "");

- pr_info("DMA domain TLB invalidation policy: %s mode %s\n",
- iommu_dma_strict ? "strict" : "lazy",
- (iommu_cmd_line & IOMMU_CMD_LINE_STRICT) ?
- "(set via kernel command line)" : "");
+ if (!iommu_default_passthrough())
+ pr_info("DMA domain TLB invalidation policy: %s mode %s\n",
+ iommu_dma_strict ? "strict" : "lazy",
+ (iommu_cmd_line & IOMMU_CMD_LINE_STRICT) ?
+ "(set via kernel command line)" : "");

return 0;
}
--
2.25.1