linux-kernel - [PATCH RFCv2 04/13] irqchip: Have CONFIG_IRQ_MSI_IOMMU be selected by the irqchips that need it

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: <a371fbe1c68e891a38f9cc8eadf2e93d4921e246.1736550979.git.nicolinc@nvidia.com>
Date: Fri, 10 Jan 2025 19:32:20 -0800
From: Nicolin Chen <nicolinc@...dia.com>
To: <will@...nel.org>, <robin.murphy@....com>, <jgg@...dia.com>,
	<kevin.tian@...el.com>, <tglx@...utronix.de>, <maz@...nel.org>,
	<alex.williamson@...hat.com>
CC: <joro@...tes.org>, <shuah@...nel.org>, <reinette.chatre@...el.com>,
	<eric.auger@...hat.com>, <yebin10@...wei.com>, <apatel@...tanamicro.com>,
	<shivamurthy.shastri@...utronix.de>, <bhelgaas@...gle.com>,
	<anna-maria@...utronix.de>, <yury.norov@...il.com>, <nipun.gupta@....com>,
	<iommu@...ts.linux.dev>, <linux-kernel@...r.kernel.org>,
	<linux-arm-kernel@...ts.infradead.org>, <kvm@...r.kernel.org>,
	<linux-kselftest@...r.kernel.org>, <patches@...ts.linux.dev>,
	<jean-philippe@...aro.org>, <mdf@...nel.org>, <mshavit@...gle.com>,
	<shameerali.kolothum.thodi@...wei.com>, <smostafa@...gle.com>,
	<ddutile@...hat.com>
Subject: [PATCH RFCv2 04/13] irqchip: Have CONFIG_IRQ_MSI_IOMMU be selected by the irqchips that need it

From: Jason Gunthorpe <jgg@...dia.com>

Currently IRQ_MSI_IOMMU is selected if DMA_IOMMU is available to provide
an implementation for iommu_dma_prepare/compose_msi_msg(). However it
makes more sense for the irqchips that call prepare/compose to select it
and that will trigger all the additional code and data to be compiled into
the kernel.

If IRQ_MSI_IOMMU is selected with no IOMMU side implementation then
prepare/compose will be NOP stubs.

If IRQ_MSI_IOMMU is not selected by an irqchip then the related code on
the iommu side is compiled out.

Signed-off-by: Jason Gunthorpe <jgg@...dia.com>
Signed-off-by: Nicolin Chen <nicolinc@...dia.com>
---
 drivers/iommu/Kconfig   | 1 -
 drivers/irqchip/Kconfig | 4 ++++
 kernel/irq/Kconfig      | 1 +
 3 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index 47c46e4b739e..b9a4f0521d71 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -154,7 +154,6 @@ config IOMMU_DMA
 	select DMA_OPS_HELPERS
 	select IOMMU_API
 	select IOMMU_IOVA
-	select IRQ_MSI_IOMMU
 	select NEED_SG_DMA_LENGTH
 	select NEED_SG_DMA_FLAGS if SWIOTLB
 
diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 9bee02db1643..758cbbf907aa 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -28,6 +28,7 @@ config ARM_GIC_V2M
 	select ARM_GIC
 	select IRQ_MSI_LIB
 	select PCI_MSI
+	select IRQ_MSI_IOMMU
 
 config GIC_NON_BANKED
 	bool
@@ -38,12 +39,14 @@ config ARM_GIC_V3
 	select PARTITION_PERCPU
 	select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP
 	select HAVE_ARM_SMCCC_DISCOVERY
+	select IRQ_MSI_IOMMU
 
 config ARM_GIC_V3_ITS
 	bool
 	select GENERIC_MSI_IRQ
 	select IRQ_MSI_LIB
 	default ARM_GIC_V3
+	select IRQ_MSI_IOMMU
 
 config ARM_GIC_V3_ITS_FSL_MC
 	bool
@@ -407,6 +410,7 @@ config LS_EXTIRQ
 
 config LS_SCFG_MSI
 	def_bool y if SOC_LS1021A || ARCH_LAYERSCAPE
+	select IRQ_MSI_IOMMU
 	depends on PCI_MSI
 
 config PARTITION_PERCPU
diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig
index 529adb1f5859..045b37073d4a 100644
--- a/kernel/irq/Kconfig
+++ b/kernel/irq/Kconfig
@@ -96,6 +96,7 @@ config GENERIC_MSI_IRQ
 	bool
 	select IRQ_DOMAIN_HIERARCHY
 
+# irqchip drivers should select this if they call iommu_dma_prepare_msi()
 config IRQ_MSI_IOMMU
 	bool
 
-- 
2.43.0