diff options
| author |   Andi Kleen <ak@suse.de> | 2006-12-07 02:14:07 +0100 |
|---|---|---|
| committer |   Andi Kleen <andi@basil.nowhere.org> | 2006-12-07 02:14:07 +0100 |
| commit | d15512f442ef1ea60f6195b0444fb27b3cf8d0e6 (patch) | |
| tree | 71764761d19509d5ffcea0b6ef9965a2f489691c /arch/i386/kernel | |
| parent | [PATCH] x86: comment magic constants in delay.h (diff) | |
| download | linux-dev-d15512f442ef1ea60f6195b0444fb27b3cf8d0e6.tar.xz linux-dev-d15512f442ef1ea60f6195b0444fb27b3cf8d0e6.zip | |
[PATCH] i386: Fix race in IO-APIC routing entry setup.
Interrupt could happen between setting the IO-APIC entry
and setting its interrupt data.
Pointed out by Linus.
Signed-off-by: Andi Kleen <ak@suse.de>
Diffstat (limited to 'arch/i386/kernel')
| -rw-r--r-- | arch/i386/kernel/io_apic.c | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/arch/i386/kernel/io_apic.c b/arch/i386/kernel/io_apic.c index 3b7a63e0ed1a..e33b7a845299 100644 --- a/arch/i386/kernel/io_apic.c +++ b/arch/i386/kernel/io_apic.c @@ -153,14 +153,20 @@ static struct IO_APIC_route_entry ioapic_read_entry(int apic, int pin) * the interrupt, and we need to make sure the entry is fully populated * before that happens. */ -static void ioapic_write_entry(int apic, int pin, struct IO_APIC_route_entry e) +static void +__ioapic_write_entry(int apic, int pin, struct IO_APIC_route_entry e) { - unsigned long flags; union entry_union eu; eu.entry = e; - spin_lock_irqsave(&ioapic_lock, flags); io_apic_write(apic, 0x11 + 2*pin, eu.w2); io_apic_write(apic, 0x10 + 2*pin, eu.w1); +} + +static void ioapic_write_entry(int apic, int pin, struct IO_APIC_route_entry e) +{ + unsigned long flags; + spin_lock_irqsave(&ioapic_lock, flags); + __ioapic_write_entry(apic, pin, e); spin_unlock_irqrestore(&ioapic_lock, flags); } @@ -1360,8 +1366,8 @@ static void __init setup_IO_APIC_irqs(void) if (!apic && (irq < 16)) disable_8259A_irq(irq); } - ioapic_write_entry(apic, pin, entry); spin_lock_irqsave(&ioapic_lock, flags); + __ioapic_write_entry(apic, pin, entry); set_native_irq_info(irq, TARGET_CPUS); spin_unlock_irqrestore(&ioapic_lock, flags); } @@ -2856,8 +2862,8 @@ int io_apic_set_pci_routing (int ioapic, int pin, int irq, int edge_level, int a if (!ioapic && (irq < 16)) disable_8259A_irq(irq); - ioapic_write_entry(ioapic, pin, entry); spin_lock_irqsave(&ioapic_lock, flags); + __ioapic_write_entry(ioapic, pin, entry); set_native_irq_info(irq, TARGET_CPUS); spin_unlock_irqrestore(&ioapic_lock, flags); |