On 6/14/21 10:57 PM, Robin Murphy wrote:
Consolidating the flush queue logic also meant that the "iommu.strict" option started taking effect on x86 as well. Make sure we document that.Fixes: a250c23f15c2 ("iommu: remove DOMAIN_ATTR_DMA_USE_FLUSH_QUEUE") Signed-off-by: Robin Murphy <robin.mur...@arm.com> --- Documentation/admin-guide/kernel-parameters.txt | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index cb89dbdedc46..20a32de990ed 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1987,7 +1987,7 @@ forcing Dual Address Cycle for PCI cards supporting greater than 32-bit addressing.- iommu.strict= [ARM64] Configure TLB invalidation behaviour+ iommu.strict= [ARM64, X86] Configure TLB invalidation behaviour Format: { "0" | "1" } 0 - Lazy mode. Request that DMA unmap operations use deferred @@ -1998,6 +1998,10 @@ 1 - Strict mode (default). DMA unmap operations invalidate IOMMU hardware TLBs synchronously. + Note: on x86, the default behaviour depends on the + equivalent driver-specific parameters, but a strict + mode explicitly specified by either method takes + precedence.iommu.passthrough=[ARM64, X86] Configure DMA to bypass the IOMMU by default.
Reviewed-by: Lu Baolu <baolu...@linux.intel.com> Best regards, baolu _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
