linux-kernel - [PATCH AUTOSEL 4.14 11/14] iommu/amd: Increase interrupt remapping table limit to 512 entries

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20201110035611.424867-11-sashal@kernel.org>
Date:   Mon,  9 Nov 2020 22:56:07 -0500
From:   Sasha Levin <sashal@...nel.org>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:     Suravee Suthikulpanit <suravee.suthikulpanit@....com>,
        Joerg Roedel <jroedel@...e.de>,
        Sasha Levin <sashal@...nel.org>,
        iommu@...ts.linux-foundation.org
Subject: [PATCH AUTOSEL 4.14 11/14] iommu/amd: Increase interrupt remapping table limit to 512 entries

From: Suravee Suthikulpanit <suravee.suthikulpanit@....com>

[ 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@....com>
Link: https://lore.kernel.org/r/20201015025002.87997-1-suravee.suthikulpanit@amd.com
Signed-off-by: Joerg Roedel <jroedel@...e.de>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 drivers/iommu/amd_iommu_types.h | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/amd_iommu_types.h b/drivers/iommu/amd_iommu_types.h
index 74c8638aac2b9..ac3cac052af9d 100644
--- a/drivers/iommu/amd_iommu_types.h
+++ b/drivers/iommu/amd_iommu_types.h
@@ -404,7 +404,11 @@ 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 {
-- 
2.27.0