acpi: add support for extended IRQ to PCI link
Subsystems (3)
PATCH v3 1/1 acpi: add support for extended IRQ to PCI link
The ACPI compiler uses the extended format when used interrupt numbers are greater than 256. The PCI link code currently only supports simple interrupt format. The IRQ numbers are represented using 32 bits when extended IRQ syntax. This patch changes the interrupt number type to 32 bits and places an upper limit of 1020 as possible interrupt id.
1020 is the maximum interrupt ID that can be assigned to an ARM SPI interrupt according to ARM architecture.
Additional checks have been placed to prevent out of bounds writes.
--- drivers/acpi/pci_link.c | 28 +++++++++++++++++++--------- 1 file changed, 19 insertions(+), 9 deletions(-)
drivers/acpi/pci_link.c +19 -9
@@ -1,6 +1,7 @@/* * pci_link.c - ACPI PCI Interrupt Link Device Driver ($Revision: 34 $) * +* Copyright (c) 2015, The Linux Foundation. All rights reserved. * Copyright (C) 2001, 2002 Andy Grover <[email protected]> * Copyright (C) 2001, 2002 Paul Diefenbaugh <[email protected]> * Copyright (C) 2002 Dominik Brodowski <[email protected]>
@@ -67,12 +68,12 @@ static struct acpi_scan_handler pci_link_handler = {* later even the link is disable. Instead, we just repick the active irq */ struct acpi_pci_link_irq { -u8 active;/* Current IRQ */ +u32 active;/* Current IRQ */ u8 triggering;/* All IRQs */ u8 polarity;/* All IRQs */ u8 resource_type;u8 possible_count; -u8 possible[ACPI_PCI_LINK_MAX_POSSIBLE ]; +u32 possible[ACPI_PCI_LINK_MAX_POSSIBLE ];u8 initialized:1 ;u8 reserved:7 ; };
@@ -437,7 +438,11 @@ static int acpi_pci_link_set(struct acpi_pci_link *link, int irq)* enabled system. */ -#define ACPI_MAX_IRQS 256 +/* +* 1020 is the maximum interrupt ID that can be assigned to +* an ARM SPI interrupt according to ARM architecture. +*/ +#define ACPI_MAX_IRQS 1020#define ACPI_MAX_ISA_IRQ 16#define PIRQ_PENALTY_PCI_AVAILABLE (0)
@@ -493,7 +498,8 @@ int __init acpi_irq_penalty_init(void) penalty; } - }else if (link->irq.active) { + }else if (link->irq.active && + (link->irq.active <ACPI_MAX_IRQS )) { acpi_irq_penalty[link->irq.active] +=PIRQ_PENALTY_PCI_POSSIBLE ; }
@@ -541,14 +547,16 @@ static int acpi_pci_link_allocate(struct acpi_pci_link *link)else irq = link->irq.possible[link->irq.possible_count -1 ]; -if (acpi_irq_balance || !link->irq.active) { +if ((acpi_irq_balance || !link->irq.active) && (irq <ACPI_MAX_IRQS )) {/* * Select the best IRQ. This is done in reverse to promote * the use of IRQs 9, 10, 11, and >15. */ -for (i = (link->irq.possible_count -1 ); i >=0 ; i--) { -if (acpi_irq_penalty[irq] > - acpi_irq_penalty[link->irq.possible[i]]) + i = link->irq.possible_count; +while (--i) { +if ((link->irq.possible[i] <ACPI_MAX_IRQS ) && + (acpi_irq_penalty[irq] > + acpi_irq_penalty[link->irq.possible[i]])) irq = link->irq.possible[i]; } }
@@ -568,7 +576,9 @@ static int acpi_pci_link_allocate(struct acpi_pci_link *link) acpi_device_bid(link->device));return -ENODEV ; }else { - acpi_irq_penalty[link->irq.active] +=PIRQ_PENALTY_PCI_USING ; +if (link->irq.active <ACPI_MAX_IRQS ) + acpi_irq_penalty[link->irq.active] += +PIRQ_PENALTY_PCI_USING ; printk(KERN_WARNING PREFIX "%s [%s] enabled at IRQ %d\n",acpi_device_name (link->device), acpi_device_bid(link->device), link->irq.active);
Signature · 2 lines
Qualcomm Technologies, Inc. on behalf of Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project
Quoted 8 lines · Sinan Kaya
The ACPI compiler uses the extended format when used interrupt numbers are greater than 256. The PCI link code currently only supports simple interrupt format. The IRQ numbers are represented using 32 bits when extended IRQ syntax. This patch changes the interrupt number type to 32 bits and places an upper limit of 1020 as possible interrupt id.
Quoted 5 lines
1020 is the maximum interrupt ID that can be assigned to an ARM SPI interrupt according to ARM architecture.
Additional checks have been placed to prevent out of bounds writes.
One comment below.
Quoted 5 lines
drivers/acpi/pci_link.c +0
-1@@ -541,14 +547,16 @@ static int acpi_pci_link_allocate(struct acpi_pci_link *link)else irq = link->irq.possible[link->irq.possible_count -1 ]; -if (acpi_irq_balance || !link->irq.active) {
drivers/acpi/pci_link.c static int acpi_pci_link_allocate(struct acpi_pci_link *link) · line 556
Quoted 10 lines
drivers/acpi/pci_link.c +3
-3+if ((acpi_irq_balance || !link->irq.active) && (irq <ACPI_MAX_IRQS )) {/* * Select the best IRQ. This is done in reverse to promote * the use of IRQs 9, 10, 11, and >15. */ -for (i = (link->irq.possible_count -1 ); i >=0 ; i--) { -if (acpi_irq_penalty[irq] > - acpi_irq_penalty[link->irq.possible[i]]) + i = link->irq.possible_count; +while (--i) {
Actually it should be (--i >= 0). Sorry if I misled you.
Quoted 6 lines
drivers/acpi/pci_link.c +3
-0+if ((link->irq.possible[i] <ACPI_MAX_IRQS ) && + (acpi_irq_penalty[irq] > + acpi_irq_penalty[link->irq.possible[i]])) irq = link->irq.possible[i]; } }
Signature · 2 lines
With Best Regards, Andy Shevchenko