Commit f440ef2a authored Oct 15, 2020 by Suravee Suthikulpanit Committed by Greg Kroah-Hartman Nov 18, 2020

iommu/amd: Increase interrupt remapping table limit to 512 entries



[ Upstream commit 73db2fc595f358460ce32bcaa3be1f0cce4a2db1 ]

Certain device drivers allocate IO queues on a per-cpu basis.
On AMD EPYC platform, which can support up-to 256 cpu threads,
this can exceed the current MAX_IRQ_PER_TABLE limit of 256,
and result in the error message:

    AMD-Vi: Failed to allocate IRTE

This has been observed with certain NVME devices.

AMD IOMMU hardware can actually support upto 512 interrupt
remapping table entries. Therefore, update the driver to
match the hardware limit.

Please note that this also increases the size of interrupt remapping
table to 8KB per device when using the 128-bit IRTE format.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Link: https://lore.kernel.org/r/20201015025002.87997-1-suravee.suthikulpanit@amd.com


Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent 509e215d

drivers/iommu/amd_iommu_types.h

+5 −1

Original line number	Diff line number	Diff line
		@@ -410,7 +410,11 @@ extern bool amd_iommu_np_cache;
		/* Only true if all IOMMUs support device IOTLBs */
		extern bool amd_iommu_iotlb_sup;

		#define MAX_IRQS_PER_TABLE 256
		/*
		* AMD IOMMU hardware only support 512 IRTEs despite
		* the architectural limitation of 2048 entries.
		*/
		#define MAX_IRQS_PER_TABLE 512
		#define IRQ_TABLE_ALIGNMENT 128

		struct irq_remap_table {