Hi Greg, as discussed on LKML [1], I made a backport of below patch for 3.18.y. It fixes several odd issues when running as Xen dom0 which started with 3.17. It should also apply to 3.17 but as far as I know there is nobody around maintaining that version. Sander and I tested the backport and it was fixing the issues we were seeing in 3.18. Could you please add the backport to the 3.18 stable tree? Thanks, Stefan [1] https://lkml.org/lkml/2015/2/5/597 --- >From 8b5b328b62248d95743ca9af7aa71c06dd808dfe Mon Sep 17 00:00:00 2001 From: Jiang Liu <jiang.liu@xxxxxxxxxxxxxxx> Date: Tue, 20 Jan 2015 10:21:05 +0800 Subject: [PATCH] x86/xen: Treat SCI interrupt as normal GSI interrupt Currently Xen Domain0 has special treatment for ACPI SCI interrupt, that is initialize irq for ACPI SCI at early stage in a special way as: xen_init_IRQ() ->pci_xen_initial_domain() ->xen_setup_acpi_sci() Allocate and initialize irq for ACPI SCI Function xen_setup_acpi_sci() calls acpi_gsi_to_irq() to get an irq number for ACPI SCI. But unfortunately acpi_gsi_to_irq() depends on IOAPIC irqdomains through following path acpi_gsi_to_irq() ->mp_map_gsi_to_irq() ->mp_map_pin_to_irq() ->check IOAPIC irqdomain For PV domains, it uses Xen event based interrupt manangement and doesn't make uses of native IOAPIC, so no irqdomains created for IOAPIC. This causes Xen domain0 fail to install interrupt handler for ACPI SCI and all ACPI events will be lost. Please refer to: https://lkml.org/lkml/2014/12/19/178 So the fix is to get rid of special treatment for ACPI SCI, just treat ACPI SCI as normal GSI interrupt as: acpi_gsi_to_irq() ->acpi_register_gsi() ->acpi_register_gsi_xen() ->xen_register_gsi() With above change, there's no need for xen_setup_acpi_sci() anymore. The above change also works with bare metal kernel too. Signed-off-by: Jiang Liu <jiang.liu@xxxxxxxxxxxxxxx> Tested-by: Sander Eikelenboom <linux@xxxxxxxxxxxxxx> Cc: Tony Luck <tony.luck@xxxxxxxxx> Cc: xen-devel@xxxxxxxxxxxxxxxxxxxx Cc: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx> Cc: David Vrabel <david.vrabel@xxxxxxxxxx> Cc: Rafael J. Wysocki <rjw@xxxxxxxxxxxxx> Cc: Len Brown <len.brown@xxxxxxxxx> Cc: Pavel Machek <pavel@xxxxxx> Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> Link: http://lkml.kernel.org/r/1421720467-7709-2-git-send-email-jiang.liu@xxxxxxxxxxxxxxx Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> (backported from commit b568b8601f05a591a7ff09d8ee1cedb5b2e815fe) Signed-off-by: Stefan Bader <stefan.bader@xxxxxxxxxxxxx> --- arch/x86/kernel/acpi/boot.c | 23 +++++++++++----------- arch/x86/pci/xen.c | 47 --------------------------------------------- 2 files changed, 12 insertions(+), 58 deletions(-) diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c index a142e77..460f498 100644 --- a/arch/x86/kernel/acpi/boot.c +++ b/arch/x86/kernel/acpi/boot.c @@ -604,18 +604,19 @@ void __init acpi_pic_sci_set_trigger(unsigned int irq, u16 trigger) int acpi_gsi_to_irq(u32 gsi, unsigned int *irqp) { - int irq; - - if (acpi_irq_model == ACPI_IRQ_MODEL_PIC) { - *irqp = gsi; - } else { - irq = mp_map_gsi_to_irq(gsi, - IOAPIC_MAP_ALLOC | IOAPIC_MAP_CHECK); - if (irq < 0) - return -1; - *irqp = irq; + int rc, irq, trigger, polarity; + + rc = acpi_get_override_irq(gsi, &trigger, &polarity); + if (rc == 0) { + trigger = trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE; + polarity = polarity ? ACPI_ACTIVE_LOW : ACPI_ACTIVE_HIGH; + irq = acpi_register_gsi(NULL, gsi, trigger, polarity); + if (irq >= 0) { + *irqp = irq; + return 0; + } } - return 0; + return -1; } EXPORT_SYMBOL_GPL(acpi_gsi_to_irq); diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c index 093f5f4..6b3cf7c 100644 --- a/arch/x86/pci/xen.c +++ b/arch/x86/pci/xen.c @@ -452,52 +452,6 @@ int __init pci_xen_hvm_init(void) } #ifdef CONFIG_XEN_DOM0 -static __init void xen_setup_acpi_sci(void) -{ - int rc; - int trigger, polarity; - int gsi = acpi_sci_override_gsi; - int irq = -1; - int gsi_override = -1; - - if (!gsi) - return; - - rc = acpi_get_override_irq(gsi, &trigger, &polarity); - if (rc) { - printk(KERN_WARNING "xen: acpi_get_override_irq failed for acpi" - " sci, rc=%d\n", rc); - return; - } - trigger = trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE; - polarity = polarity ? ACPI_ACTIVE_LOW : ACPI_ACTIVE_HIGH; - - printk(KERN_INFO "xen: sci override: global_irq=%d trigger=%d " - "polarity=%d\n", gsi, trigger, polarity); - - /* Before we bind the GSI to a Linux IRQ, check whether - * we need to override it with bus_irq (IRQ) value. Usually for - * IRQs below IRQ_LEGACY_IRQ this holds IRQ == GSI, as so: - * ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 low level) - * but there are oddballs where the IRQ != GSI: - * ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 20 low level) - * which ends up being: gsi_to_irq[9] == 20 - * (which is what acpi_gsi_to_irq ends up calling when starting the - * the ACPI interpreter and keels over since IRQ 9 has not been - * setup as we had setup IRQ 20 for it). - */ - if (acpi_gsi_to_irq(gsi, &irq) == 0) { - /* Use the provided value if it's valid. */ - if (irq >= 0) - gsi_override = irq; - } - - gsi = xen_register_gsi(gsi, gsi_override, trigger, polarity); - printk(KERN_INFO "xen: acpi sci %d\n", gsi); - - return; -} - int __init pci_xen_initial_domain(void) { int irq; @@ -509,7 +463,6 @@ int __init pci_xen_initial_domain(void) x86_msi.msi_mask_irq = xen_nop_msi_mask_irq; x86_msi.msix_mask_irq = xen_nop_msix_mask_irq; #endif - xen_setup_acpi_sci(); __acpi_register_gsi = acpi_register_gsi_xen; /* Pre-allocate legacy irqs */ for (irq = 0; irq < nr_legacy_irqs(); irq++) { -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html