From 2e8cb2cf1bd6e90f58bd517eb9ca1938e64fa51c Mon Sep 17 00:00:00 2001 From: Rob Herring Date: Mon, 14 Jan 2019 15:35:46 -0600 Subject: [PATCH 1/3] PCI: Fix PCI kconfig menu organization After commit eb01d42a7778 ("PCI: consolidate PCI config entry in drivers/pci"), all the PCI kconfig options appear below "PCI support" rather than within a sub-menu. This is because menuconfig expects all kconfig entries to be enclosed in an if/endif section. Add the missing if/endif. With this, "depends on PCI" is redundant in the sub-menu entries and can be removed. Fixes: eb01d42a7778 ("PCI: consolidate PCI config entry in drivers/pci") Signed-off-by: Rob Herring Signed-off-by: Bjorn Helgaas Reviewed-by: Christoph Hellwig --- drivers/pci/Kconfig | 22 ++++++++-------------- 1 file changed, 8 insertions(+), 14 deletions(-) diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig index 4310c7a4212e..2ab92409210a 100644 --- a/drivers/pci/Kconfig +++ b/drivers/pci/Kconfig @@ -21,13 +21,14 @@ menuconfig PCI support for PCI-X and the foundations for PCI Express support. Say 'Y' here unless you know what you are doing. +if PCI + config PCI_DOMAINS bool depends on PCI config PCI_DOMAINS_GENERIC bool - depends on PCI select PCI_DOMAINS config PCI_SYSCALL @@ -37,7 +38,6 @@ source "drivers/pci/pcie/Kconfig" config PCI_MSI bool "Message Signaled Interrupts (MSI and MSI-X)" - depends on PCI select GENERIC_MSI_IRQ help This allows device drivers to enable MSI (Message Signaled @@ -59,7 +59,6 @@ config PCI_MSI_IRQ_DOMAIN config PCI_QUIRKS default y bool "Enable PCI quirk workarounds" if EXPERT - depends on PCI help This enables workarounds for various PCI chipset bugs/quirks. Disable this only if your target machine is unaffected by PCI @@ -67,7 +66,7 @@ config PCI_QUIRKS config PCI_DEBUG bool "PCI Debugging" - depends on PCI && DEBUG_KERNEL + depends on DEBUG_KERNEL help Say Y here if you want the PCI core to produce a bunch of debug messages to the system log. Select this if you are having a @@ -77,7 +76,6 @@ config PCI_DEBUG config PCI_REALLOC_ENABLE_AUTO bool "Enable PCI resource re-allocation detection" - depends on PCI depends on PCI_IOV help Say Y here if you want the PCI core to detect if PCI resource @@ -90,7 +88,6 @@ config PCI_REALLOC_ENABLE_AUTO config PCI_STUB tristate "PCI Stub driver" - depends on PCI help Say Y or M here if you want be able to reserve a PCI device when it is going to be assigned to a guest operating system. @@ -99,7 +96,6 @@ config PCI_STUB config PCI_PF_STUB tristate "PCI PF Stub driver" - depends on PCI depends on PCI_IOV help Say Y or M here if you want to enable support for devices that @@ -111,7 +107,7 @@ config PCI_PF_STUB config XEN_PCIDEV_FRONTEND tristate "Xen PCI Frontend" - depends on PCI && X86 && XEN + depends on X86 && XEN select PCI_XEN select XEN_XENBUS_FRONTEND default y @@ -133,7 +129,6 @@ config PCI_BRIDGE_EMUL config PCI_IOV bool "PCI IOV support" - depends on PCI select PCI_ATS help I/O Virtualization is a PCI feature supported by some devices @@ -144,7 +139,6 @@ config PCI_IOV config PCI_PRI bool "PCI PRI support" - depends on PCI select PCI_ATS help PRI is the PCI Page Request Interface. It allows PCI devices that are @@ -154,7 +148,6 @@ config PCI_PRI config PCI_PASID bool "PCI PASID support" - depends on PCI select PCI_ATS help Process Address Space Identifiers (PASIDs) can be used by PCI devices @@ -167,7 +160,7 @@ config PCI_PASID config PCI_P2PDMA bool "PCI peer-to-peer transfer support" - depends on PCI && ZONE_DEVICE + depends on ZONE_DEVICE select GENERIC_ALLOCATOR help Enableѕ drivers to do PCI peer-to-peer transactions to and from @@ -184,12 +177,11 @@ config PCI_P2PDMA config PCI_LABEL def_bool y if (DMI || ACPI) - depends on PCI select NLS config PCI_HYPERV tristate "Hyper-V PCI Frontend" - depends on PCI && X86 && HYPERV && PCI_MSI && PCI_MSI_IRQ_DOMAIN && X86_64 + depends on X86 && HYPERV && PCI_MSI && PCI_MSI_IRQ_DOMAIN && X86_64 help The PCI device frontend driver allows the kernel to import arbitrary PCI devices from a PCI backend to support PCI driver domains. @@ -198,3 +190,5 @@ source "drivers/pci/hotplug/Kconfig" source "drivers/pci/controller/Kconfig" source "drivers/pci/endpoint/Kconfig" source "drivers/pci/switch/Kconfig" + +endif From 77f88abd4a6f73a1a68dbdc0e3f21575fd508fc3 Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Tue, 15 Jan 2019 17:31:29 -0600 Subject: [PATCH 2/3] PCI/MSI: Return -ENOSPC from pci_alloc_irq_vectors_affinity() The API of pci_alloc_irq_vectors_affinity() says it returns -ENOSPC if fewer than @min_vecs interrupt vectors are available for @dev. However, if a device supports MSI-X but not MSI and a caller requests @min_vecs that can't be satisfied by MSI-X, we previously returned -EINVAL (from the failed attempt to enable MSI), not -ENOSPC. When -ENOSPC is returned, callers may reduce the number IRQs they request and try again. Most callers can use the @min_vecs and @max_vecs parameters to avoid this retry loop, but that doesn't work when using IRQ affinity "nr_sets" because rebalancing the sets is driver-specific. This return value bug has been present since pci_alloc_irq_vectors() was added in v4.10 by aff171641d18 ("PCI: Provide sensible IRQ vector alloc/free routines"), but it wasn't an issue because @min_vecs/@max_vecs removed the need for callers to iteratively reduce the number of IRQs requested and retry the allocation, so they didn't need to distinguish -ENOSPC from -EINVAL. In v5.0, 6da4b3ab9a6e ("genirq/affinity: Add support for allocating interrupt sets") added IRQ sets to the interface, which reintroduced the need to check for -ENOSPC and possibly reduce the number of IRQs requested and retry the allocation. Signed-off-by: Ming Lei [bhelgaas: changelog] Signed-off-by: Bjorn Helgaas Cc: Jens Axboe Cc: Keith Busch Cc: Christoph Hellwig --- drivers/pci/msi.c | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-) diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 7a1c8a09efa5..4c0b47867258 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -1168,7 +1168,8 @@ int pci_alloc_irq_vectors_affinity(struct pci_dev *dev, unsigned int min_vecs, const struct irq_affinity *affd) { static const struct irq_affinity msi_default_affd; - int vecs = -ENOSPC; + int msix_vecs = -ENOSPC; + int msi_vecs = -ENOSPC; if (flags & PCI_IRQ_AFFINITY) { if (!affd) @@ -1179,16 +1180,17 @@ int pci_alloc_irq_vectors_affinity(struct pci_dev *dev, unsigned int min_vecs, } if (flags & PCI_IRQ_MSIX) { - vecs = __pci_enable_msix_range(dev, NULL, min_vecs, max_vecs, - affd); - if (vecs > 0) - return vecs; + msix_vecs = __pci_enable_msix_range(dev, NULL, min_vecs, + max_vecs, affd); + if (msix_vecs > 0) + return msix_vecs; } if (flags & PCI_IRQ_MSI) { - vecs = __pci_enable_msi_range(dev, min_vecs, max_vecs, affd); - if (vecs > 0) - return vecs; + msi_vecs = __pci_enable_msi_range(dev, min_vecs, max_vecs, + affd); + if (msi_vecs > 0) + return msi_vecs; } /* use legacy irq if allowed */ @@ -1199,7 +1201,9 @@ int pci_alloc_irq_vectors_affinity(struct pci_dev *dev, unsigned int min_vecs, } } - return vecs; + if (msix_vecs == -ENOSPC) + return -ENOSPC; + return msi_vecs; } EXPORT_SYMBOL(pci_alloc_irq_vectors_affinity); From d2fd6e81912a665993b24dcdc1c1384a42a54f7e Mon Sep 17 00:00:00 2001 From: Logan Gunthorpe Date: Thu, 17 Jan 2019 08:46:34 -0600 Subject: [PATCH 3/3] PCI: Fix __initdata issue with "pci=disable_acs_redir" parameter The disable_acs_redir parameter stores a pointer to the string passed to pci_setup(). However, the string passed to PCI setup is actually a temporary copy allocated in static __initdata memory. After init, once the memory is freed, it is no longer valid to reference this pointer. This bug was noticed in v5.0-rc1 after a change in commit c5eb1190074c ("PCI / PM: Allow runtime PM without callback functions") caused pci_disable_acs_redir() to be called during shutdown which manifested as an unable to handle kernel paging request at: RIP: 0010:pci_enable_acs+0x3f/0x1e0 Call Trace: pci_restore_state.part.44+0x159/0x3c0 pci_restore_standard_config+0x33/0x40 pci_pm_runtime_resume+0x2b/0xd0 ? pci_restore_standard_config+0x40/0x40 __rpm_callback+0xbc/0x1b0 rpm_callback+0x1f/0x70 ? pci_restore_standard_config+0x40/0x40 rpm_resume+0x4f9/0x710 ? pci_conf1_read+0xb6/0xf0 ? pci_conf1_write+0xb2/0xe0 __pm_runtime_resume+0x47/0x70 pci_device_shutdown+0x1e/0x60 device_shutdown+0x14a/0x1f0 kernel_restart+0xe/0x50 __do_sys_reboot+0x1ee/0x210 ? __fput+0x144/0x1d0 do_writev+0x5e/0xf0 ? do_writev+0x5e/0xf0 do_syscall_64+0x48/0xf0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 It was also likely possible to trigger this bug when hotplugging PCI devices. To fix this, instead of storing a pointer, we use kstrdup() to copy the disable_acs_redir_param to its own buffer which will never be freed. Fixes: aaca43fda742 ("PCI: Add "pci=disable_acs_redir=" parameter for peer-to-peer support") Tested-by: Jarkko Nikula Signed-off-by: Logan Gunthorpe Signed-off-by: Bjorn Helgaas Reviewed-by: Jarkko Nikula --- drivers/pci/pci.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index c9d8e3c837de..c25acace7d91 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -6195,7 +6195,8 @@ static int __init pci_setup(char *str) } else if (!strncmp(str, "pcie_scan_all", 13)) { pci_add_flags(PCI_SCAN_ALL_PCIE_DEVS); } else if (!strncmp(str, "disable_acs_redir=", 18)) { - disable_acs_redir_param = str + 18; + disable_acs_redir_param = + kstrdup(str + 18, GFP_KERNEL); } else { printk(KERN_ERR "PCI: Unknown option `%s'\n", str);