Commit ea094d53 authored Apr 17, 2019 by Wenwen Wang Committed by Bjorn Helgaas Apr 17, 2019

x86/PCI: Fix PCI IRQ routing table memory leak



In pcibios_irq_init(), the PCI IRQ routing table 'pirq_table' is first
found through pirq_find_routing_table().  If the table is not found and
CONFIG_PCI_BIOS is defined, the table is then allocated in
pcibios_get_irq_routing_table() using kmalloc().  Later, if the I/O APIC is
used, this table is actually not used.  In that case, the allocated table
is not freed, which is a memory leak.

Free the allocated table if it is not used.

Signed-off-by: Wenwen Wang <wang6495@umn.edu>
[bhelgaas: added Ingo's reviewed-by, since the only change since v1 was to
use the irq_routing_table local variable name he suggested]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>

parent 804ee5be

arch/x86/pci/irq.c

+8 −2

Original line number	Diff line number	Diff line
		@@ -1119,6 +1119,8 @@ static const struct dmi_system_id pciirq_dmi_table[] __initconst = {

		void __init pcibios_irq_init(void)
		{
		struct irq_routing_table *rtable = NULL;

		DBG(KERN_DEBUG "PCI: IRQ init\n");

		if (raw_pci_ops == NULL)
		@@ -1129,8 +1131,10 @@ void __init pcibios_irq_init(void)
		pirq_table = pirq_find_routing_table();

		#ifdef CONFIG_PCI_BIOS
		if (!pirq_table && (pci_probe & PCI_BIOS_IRQ_SCAN))
		if (!pirq_table && (pci_probe & PCI_BIOS_IRQ_SCAN)) {
		pirq_table = pcibios_get_irq_routing_table();
		rtable = pirq_table;
		}
		#endif
		if (pirq_table) {
		pirq_peer_trick();
		@@ -1145,9 +1149,11 @@ void __init pcibios_irq_init(void)
		* If we're using the I/O APIC, avoid using the PCI IRQ
		* routing table
		*/
		if (io_apic_assign_pci_irqs)
		if (io_apic_assign_pci_irqs) {
		kfree(rtable);
		pirq_table = NULL;
		}
		}

		x86_init.pci.fixup_irqs();