From: Qian Cai <cai@redhat.com>
To: Thomas Gleixner <tglx@linutronix.de>,
LKML <linux-kernel@vger.kernel.org>,
Heiko Carstens <hca@linux.ibm.com>,
Vasily Gorbik <gor@linux.ibm.com>,
Christian Borntraeger <borntraeger@de.ibm.com>,
linux-s390@vger.kernel.org,
Stephen Rothwell <sfr@canb.auug.org.au>,
linux-next@vger.kernel.org
Cc: Dimitri Sivanich <sivanich@hpe.com>,
linux-hyperv@vger.kernel.org, Steve Wahl <steve.wahl@hpe.com>,
linux-pci@vger.kernel.org, "K. Y. Srinivasan" <kys@microsoft.com>,
Dan Williams <dan.j.williams@intel.com>,
Wei Liu <wei.liu@kernel.org>,
Stephen Hemminger <sthemmin@microsoft.com>,
Baolu Lu <baolu.lu@intel.com>, Marc Zyngier <maz@kernel.org>,
x86@kernel.org, Jason Gunthorpe <jgg@mellanox.com>,
Megha Dey <megha.dey@intel.com>,
xen-devel@lists.xenproject.org, Kevin Tian <kevin.tian@intel.com>,
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
Haiyang Zhang <haiyangz@microsoft.com>,
Alex Williamson <alex.williamson@redhat.com>,
Stefano Stabellini <sstabellini@kernel.org>,
Bjorn Helgaas <bhelgaas@google.com>,
Dave Jiang <dave.jiang@intel.com>,
Boris Ostrovsky <boris.ostrovsky@oracle.com>,
Jon Derrick <jonathan.derrick@intel.com>,
Juergen Gross <jgross@suse.com>, Russ Anderson <rja@hpe.com>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
iommu@lists.linux-foundation.org,
Jacob Pan <jacob.jun.pan@intel.com>,
"Rafael J. Wysocki" <rafael@kernel.org>
Subject: Re: [patch V2 34/46] PCI/MSI: Make arch_.*_msi_irq[s] fallbacks selectable
Date: Fri, 25 Sep 2020 09:54:52 -0400 [thread overview]
Message-ID: <cdfd63305caa57785b0925dd24c0711ea02c8527.camel@redhat.com> (raw)
In-Reply-To: <20200826112333.992429909@linutronix.de>
On Wed, 2020-08-26 at 13:17 +0200, Thomas Gleixner wrote:
> From: Thomas Gleixner <tglx@linutronix.de>
>
> The arch_.*_msi_irq[s] fallbacks are compiled in whether an architecture
> requires them or not. Architectures which are fully utilizing hierarchical
> irq domains should never call into that code.
>
> It's not only architectures which depend on that by implementing one or
> more of the weak functions, there is also a bunch of drivers which relies
> on the weak functions which invoke msi_controller::setup_irq[s] and
> msi_controller::teardown_irq.
>
> Make the architectures and drivers which rely on them select them in Kconfig
> and if not selected replace them by stub functions which emit a warning and
> fail the PCI/MSI interrupt allocation.
>
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Today's linux-next will have some warnings on s390x:
.config: https://gitlab.com/cailca/linux-mm/-/blob/master/s390.config
WARNING: unmet direct dependencies detected for PCI_MSI_ARCH_FALLBACKS
Depends on [n]: PCI [=n]
Selected by [y]:
- S390 [=y]
WARNING: unmet direct dependencies detected for PCI_MSI_ARCH_FALLBACKS
Depends on [n]: PCI [=n]
Selected by [y]:
- S390 [=y]
> ---
> V2: Make the architectures (and drivers) which need the fallbacks select them
> and not the other way round (Bjorn).
> ---
> arch/ia64/Kconfig | 1 +
> arch/mips/Kconfig | 1 +
> arch/powerpc/Kconfig | 1 +
> arch/s390/Kconfig | 1 +
> arch/sparc/Kconfig | 1 +
> arch/x86/Kconfig | 1 +
> drivers/pci/Kconfig | 3 +++
> drivers/pci/controller/Kconfig | 3 +++
> drivers/pci/msi.c | 3 ++-
> include/linux/msi.h | 31 ++++++++++++++++++++++++++-----
> 10 files changed, 40 insertions(+), 6 deletions(-)
>
> --- a/arch/ia64/Kconfig
> +++ b/arch/ia64/Kconfig
> @@ -56,6 +56,7 @@ config IA64
> select NEED_DMA_MAP_STATE
> select NEED_SG_DMA_LENGTH
> select NUMA if !FLATMEM
> + select PCI_MSI_ARCH_FALLBACKS
> default y
> help
> The Itanium Processor Family is Intel's 64-bit successor to
> --- a/arch/mips/Kconfig
> +++ b/arch/mips/Kconfig
> @@ -86,6 +86,7 @@ config MIPS
> select MODULES_USE_ELF_REL if MODULES
> select MODULES_USE_ELF_RELA if MODULES && 64BIT
> select PERF_USE_VMALLOC
> + select PCI_MSI_ARCH_FALLBACKS
> select RTC_LIB
> select SYSCTL_EXCEPTION_TRACE
> select VIRT_TO_BUS
> --- a/arch/powerpc/Kconfig
> +++ b/arch/powerpc/Kconfig
> @@ -246,6 +246,7 @@ config PPC
> select OLD_SIGACTION if PPC32
> select OLD_SIGSUSPEND
> select PCI_DOMAINS if PCI
> + select PCI_MSI_ARCH_FALLBACKS
> select PCI_SYSCALL if PCI
> select PPC_DAWR if PPC64
> select RTC_LIB
> --- a/arch/s390/Kconfig
> +++ b/arch/s390/Kconfig
> @@ -185,6 +185,7 @@ config S390
> select OLD_SIGSUSPEND3
> select PCI_DOMAINS if PCI
> select PCI_MSI if PCI
> + select PCI_MSI_ARCH_FALLBACKS
> select SPARSE_IRQ
> select SYSCTL_EXCEPTION_TRACE
> select THREAD_INFO_IN_TASK
> --- a/arch/sparc/Kconfig
> +++ b/arch/sparc/Kconfig
> @@ -43,6 +43,7 @@ config SPARC
> select GENERIC_STRNLEN_USER
> select MODULES_USE_ELF_RELA
> select PCI_SYSCALL if PCI
> + select PCI_MSI_ARCH_FALLBACKS
> select ODD_RT_SIGACTION
> select OLD_SIGSUSPEND
> select CPU_NO_EFFICIENT_FFS
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -225,6 +225,7 @@ config X86
> select NEED_SG_DMA_LENGTH
> select PCI_DOMAINS if PCI
> select PCI_LOCKLESS_CONFIG if PCI
> + select PCI_MSI_ARCH_FALLBACKS
> select PERF_EVENTS
> select RTC_LIB
> select RTC_MC146818_LIB
> --- a/drivers/pci/Kconfig
> +++ b/drivers/pci/Kconfig
> @@ -56,6 +56,9 @@ config PCI_MSI_IRQ_DOMAIN
> depends on PCI_MSI
> select GENERIC_MSI_IRQ_DOMAIN
>
> +config PCI_MSI_ARCH_FALLBACKS
> + bool
> +
> config PCI_QUIRKS
> default y
> bool "Enable PCI quirk workarounds" if EXPERT
> --- a/drivers/pci/controller/Kconfig
> +++ b/drivers/pci/controller/Kconfig
> @@ -41,6 +41,7 @@ config PCI_TEGRA
> bool "NVIDIA Tegra PCIe controller"
> depends on ARCH_TEGRA || COMPILE_TEST
> depends on PCI_MSI_IRQ_DOMAIN
> + select PCI_MSI_ARCH_FALLBACKS
> help
> Say Y here if you want support for the PCIe host controller found
> on NVIDIA Tegra SoCs.
> @@ -67,6 +68,7 @@ config PCIE_RCAR_HOST
> bool "Renesas R-Car PCIe host controller"
> depends on ARCH_RENESAS || COMPILE_TEST
> depends on PCI_MSI_IRQ_DOMAIN
> + select PCI_MSI_ARCH_FALLBACKS
> help
> Say Y here if you want PCIe controller support on R-Car SoCs in host
> mode.
> @@ -103,6 +105,7 @@ config PCIE_XILINX_CPM
> bool "Xilinx Versal CPM host bridge support"
> depends on ARCH_ZYNQMP || COMPILE_TEST
> select PCI_HOST_COMMON
> + select PCI_MSI_ARCH_FALLBACKS
> help
> Say 'Y' here if you want kernel support for the
> Xilinx Versal CPM host bridge.
> --- a/drivers/pci/msi.c
> +++ b/drivers/pci/msi.c
> @@ -58,8 +58,8 @@ static void pci_msi_teardown_msi_irqs(st
> #define pci_msi_teardown_msi_irqs arch_teardown_msi_irqs
> #endif
>
> +#ifdef CONFIG_PCI_MSI_ARCH_FALLBACKS
> /* Arch hooks */
> -
> int __weak arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc)
> {
> struct msi_controller *chip = dev->bus->msi;
> @@ -132,6 +132,7 @@ void __weak arch_teardown_msi_irqs(struc
> {
> return default_teardown_msi_irqs(dev);
> }
> +#endif /* CONFIG_PCI_MSI_ARCH_FALLBACKS */
>
> static void default_restore_msi_irq(struct pci_dev *dev, int irq)
> {
> --- a/include/linux/msi.h
> +++ b/include/linux/msi.h
> @@ -193,17 +193,38 @@ void pci_msi_mask_irq(struct irq_data *d
> void pci_msi_unmask_irq(struct irq_data *data);
>
> /*
> - * The arch hooks to setup up msi irqs. Those functions are
> - * implemented as weak symbols so that they /can/ be overriden by
> - * architecture specific code if needed.
> + * The arch hooks to setup up msi irqs. Default functions are implemented
> + * as weak symbols so that they /can/ be overriden by architecture specific
> + * code if needed. These hooks must be enabled by the architecture or by
> + * drivers which depend on them via msi_controller based MSI handling.
> + *
> + * If CONFIG_PCI_MSI_ARCH_FALLBACKS is not selected they are replaced by
> + * stubs with warnings.
> */
> +#ifdef CONFIG_PCI_MSI_DISABLE_ARCH_FALLBACKS
> int arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc);
> void arch_teardown_msi_irq(unsigned int irq);
> int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type);
> void arch_teardown_msi_irqs(struct pci_dev *dev);
> -void arch_restore_msi_irqs(struct pci_dev *dev);
> -
> void default_teardown_msi_irqs(struct pci_dev *dev);
> +#else
> +static inline int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int
> type)
> +{
> + WARN_ON_ONCE(1);
> + return -ENODEV;
> +}
> +
> +static inline void arch_teardown_msi_irqs(struct pci_dev *dev)
> +{
> + WARN_ON_ONCE(1);
> +}
> +#endif
> +
> +/*
> + * The restore hooks are still available as they are useful even
> + * for fully irq domain based setups. Courtesy to XEN/X86.
> + */
> +void arch_restore_msi_irqs(struct pci_dev *dev);
> void default_restore_msi_irqs(struct pci_dev *dev);
>
> struct msi_controller {
>
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next prev parent reply other threads:[~2020-09-25 14:54 UTC|newest]
Thread overview: 121+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-08-26 11:16 [patch V2 00/46] x86, PCI, XEN, genirq ...: Prepare for device MSI Thomas Gleixner
2020-08-26 11:16 ` [patch V2 01/46] iommu/amd: Prevent NULL pointer dereference Thomas Gleixner
2020-08-27 14:57 ` Joerg Roedel
2020-08-26 11:16 ` [patch V2 02/46] x86/init: Remove unused init ops Thomas Gleixner
2020-08-26 11:16 ` [patch V2 03/46] PCI: vmd: Dont abuse vector irqomain as parent Thomas Gleixner
2020-08-26 11:16 ` [patch V2 04/46] genirq/chip: Use the first chip in irq_chip_compose_msi_msg() Thomas Gleixner
2020-08-26 19:50 ` Marc Zyngier
2020-08-26 21:19 ` Thomas Gleixner
2020-08-26 21:32 ` Marc Zyngier
2020-08-26 11:16 ` [patch V2 05/46] x86/msi: Move compose message callback where it belongs Thomas Gleixner
2020-08-26 11:16 ` [patch V2 06/46] x86/msi: Remove pointless vcpu_affinity callback Thomas Gleixner
2020-08-26 11:16 ` [patch V2 07/46] x86/irq: Rename X86_IRQ_ALLOC_TYPE_MSI* to reflect PCI dependency Thomas Gleixner
2020-08-26 11:16 ` [patch V2 08/46] x86/irq: Add allocation type for parent domain retrieval Thomas Gleixner
2020-08-26 11:16 ` [patch V2 09/46] iommu/vt-d: Consolidate irq domain getter Thomas Gleixner
2020-08-26 11:16 ` [patch V2 10/46] iommu/amd: " Thomas Gleixner
2020-08-26 11:16 ` [patch V2 11/46] iommu/irq_remapping: Consolidate irq domain lookup Thomas Gleixner
2020-08-26 11:16 ` [patch V2 12/46] x86/irq: Prepare consolidation of irq_alloc_info Thomas Gleixner
2020-08-26 11:16 ` [patch V2 13/46] x86/msi: Consolidate HPET allocation Thomas Gleixner
2020-08-26 11:16 ` [patch V2 14/46] x86/ioapic: Consolidate IOAPIC allocation Thomas Gleixner
2020-09-08 13:35 ` Wei Liu
2020-08-26 11:16 ` [patch V2 15/46] x86/irq: Consolidate DMAR irq allocation Thomas Gleixner
2020-08-26 16:50 ` Dey, Megha
2020-08-26 18:32 ` Thomas Gleixner
2020-08-26 20:50 ` Thomas Gleixner
2020-08-28 0:12 ` Dey, Megha
2020-08-26 11:16 ` [patch V2 16/46] x86/irq: Consolidate UV domain allocation Thomas Gleixner
2020-08-26 11:16 ` [patch V2 17/46] PCI/MSI: Rework pci_msi_domain_calc_hwirq() Thomas Gleixner
2020-08-26 20:24 ` Marc Zyngier
2020-08-26 11:16 ` [patch V2 18/46] x86/msi: Consolidate MSI allocation Thomas Gleixner
2020-09-08 13:36 ` Wei Liu
2020-08-26 11:16 ` [patch V2 19/46] x86/msi: Use generic MSI domain ops Thomas Gleixner
2020-08-26 20:21 ` Marc Zyngier
2020-08-26 20:43 ` Thomas Gleixner
2020-08-26 11:16 ` [patch V2 20/46] x86/irq: Move apic_post_init() invocation to one place Thomas Gleixner
2020-08-26 11:16 ` [patch V2 21/46] x86/pci: Reducde #ifdeffery in PCI init code Thomas Gleixner
2020-08-26 11:16 ` [patch V2 22/46] x86/irq: Initialize PCI/MSI domain at PCI init time Thomas Gleixner
2020-08-26 11:16 ` [patch V2 23/46] irqdomain/msi: Provide DOMAIN_BUS_VMD_MSI Thomas Gleixner
2020-08-26 20:42 ` Marc Zyngier
2020-08-26 20:57 ` Derrick, Jonathan
2020-08-26 11:16 ` [patch V2 24/46] PCI: vmd: Mark VMD irqdomain with DOMAIN_BUS_VMD_MSI Thomas Gleixner
2020-08-26 20:47 ` Marc Zyngier
2020-08-31 14:39 ` Jason Gunthorpe
2020-09-30 12:45 ` Derrick, Jonathan
2020-09-30 12:57 ` Jason Gunthorpe
2020-09-30 13:08 ` Derrick, Jonathan
2020-09-30 18:47 ` Jason Gunthorpe
2020-08-26 11:16 ` [patch V2 25/46] PCI/MSI: Provide pci_dev_has_special_msi_domain() helper Thomas Gleixner
2020-08-26 11:16 ` [patch V2 26/46] x86/xen: Make xen_msi_init() static and rename it to xen_hvm_msi_init() Thomas Gleixner
2020-08-26 11:16 ` [patch V2 27/46] x86/xen: Rework MSI teardown Thomas Gleixner
2020-08-27 7:46 ` Jürgen Groß
2020-08-26 11:16 ` [patch V2 28/46] x86/xen: Consolidate XEN-MSI init Thomas Gleixner
2020-08-27 7:47 ` Jürgen Groß
2020-08-26 11:16 ` [patch V2 29/46] irqdomain/msi: Allow to override msi_domain_alloc/free_irqs() Thomas Gleixner
2020-08-26 19:06 ` Marc Zyngier
2020-08-26 19:47 ` Thomas Gleixner
2020-08-26 21:33 ` Marc Zyngier
2020-08-28 0:24 ` Dey, Megha
2020-08-26 11:16 ` [patch V2 30/46] x86/xen: Wrap XEN MSI management into irqdomain Thomas Gleixner
2020-08-26 11:16 ` [patch V2 31/46] iommm/vt-d: Store irq domain in struct device Thomas Gleixner
2020-08-26 11:17 ` [patch V2 32/46] iommm/amd: " Thomas Gleixner
2020-08-26 11:17 ` [patch V2 33/46] x86/pci: Set default irq domain in pcibios_add_device() Thomas Gleixner
2020-08-26 11:17 ` [patch V2 34/46] PCI/MSI: Make arch_.*_msi_irq[s] fallbacks selectable Thomas Gleixner
2020-08-26 15:53 ` Thomas Gleixner
2020-08-26 21:14 ` Marc Zyngier
2020-08-26 21:27 ` Thomas Gleixner
2020-08-27 18:20 ` Bjorn Helgaas
2020-08-28 11:21 ` Lorenzo Pieralisi
2020-08-28 12:19 ` Jason Gunthorpe
2020-08-28 12:47 ` Marc Zyngier
2020-08-28 12:54 ` Jason Gunthorpe
2020-08-28 13:52 ` Marc Zyngier
2020-08-28 18:29 ` Thomas Gleixner
2020-09-25 13:54 ` Qian Cai [this message]
2020-09-26 12:38 ` Vasily Gorbik
2020-09-28 10:11 ` Thomas Gleixner
2020-08-26 11:17 ` [patch V2 35/46] x86/irq: Cleanup the arch_*_msi_irqs() leftovers Thomas Gleixner
2020-08-26 11:17 ` [patch V2 36/46] x86/irq: Make most MSI ops XEN private Thomas Gleixner
2020-08-26 11:17 ` [patch V2 37/46] iommu/vt-d: Remove domain search for PCI/MSI[X] Thomas Gleixner
2020-08-26 11:17 ` [patch V2 38/46] iommu/amd: Remove domain search for PCI/MSI Thomas Gleixner
2020-08-26 11:17 ` [patch V2 39/46] x86/irq: Add DEV_MSI allocation type Thomas Gleixner
2020-08-26 11:17 ` [patch V2 40/46] x86/msi: Rename and rework pci_msi_prepare() to cover non-PCI MSI Thomas Gleixner
2020-08-26 11:17 ` [patch V2 41/46] platform-msi: Provide default irq_chip:: Ack Thomas Gleixner
2020-08-26 21:25 ` Marc Zyngier
2020-08-26 11:17 ` [patch V2 42/46] genirq/proc: Take buslock on affinity write Thomas Gleixner
2020-08-26 11:17 ` [patch V2 43/46] genirq/msi: Provide and use msi_domain_set_default_info_flags() Thomas Gleixner
2020-08-27 8:17 ` Marc Zyngier
2020-08-28 18:42 ` Thomas Gleixner
2020-08-26 11:17 ` [patch V2 44/46] platform-msi: Add device MSI infrastructure Thomas Gleixner
2020-08-26 11:17 ` [patch V2 45/46] irqdomain/msi: Provide msi_alloc/free_store() callbacks Thomas Gleixner
2020-08-26 11:17 ` [patch V2 46/46] irqchip: Add IMS (Interrupt Message Storm) driver - NOT FOR MERGING Thomas Gleixner
2020-08-31 14:45 ` Jason Gunthorpe
2020-08-28 11:41 ` [patch V2 00/46] x86, PCI, XEN, genirq ...: Prepare for device MSI Joerg Roedel
2020-08-31 0:51 ` Lu Baolu
2020-08-31 7:10 ` Thomas Gleixner
2020-08-31 7:29 ` Lu Baolu
2020-09-01 9:06 ` Boqun Feng
2020-09-03 16:35 ` Raj, Ashok
2020-09-03 18:12 ` Thomas Gleixner
2020-09-08 3:39 ` Russ Anderson
2020-09-25 15:29 ` Qian Cai
2020-09-25 15:49 ` Peter Zijlstra
2020-09-25 23:14 ` Thomas Gleixner
2020-09-27 8:46 ` [PATCH] x86/apic/msi: Unbreak DMAR and HPET MSI Thomas Gleixner
2020-09-29 23:03 ` [patch V2 00/46] x86, PCI, XEN, genirq ...: Prepare for device MSI Dey, Megha
2020-09-30 6:41 ` Thomas Gleixner
2020-09-30 11:43 ` Jason Gunthorpe
2020-09-30 15:20 ` Thomas Gleixner
2020-09-30 17:25 ` Dey, Megha
2020-09-30 18:11 ` Thomas Gleixner
2020-11-12 12:55 ` REGRESSION: " Jason Gunthorpe
2020-11-12 14:15 ` Thomas Gleixner
2020-11-12 15:18 ` Thomas Gleixner
2020-11-12 19:15 ` iommu/vt-d: Cure VF irqdomain hickup Thomas Gleixner
2020-11-12 21:34 ` Thomas Gleixner
2020-11-13 9:19 ` Marc Zyngier
2020-11-13 13:52 ` Thomas Gleixner
2020-11-13 7:20 ` Lu Baolu
2020-11-16 9:47 ` Geert Uytterhoeven
2020-11-16 12:50 ` Thomas Gleixner
2020-11-16 12:50 ` Lu Baolu
2020-11-16 23:22 ` Jason Gunthorpe
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