Re: linux-next: Tree for June 13: IO APIC breakage on HP nx6325
From: Thomas Gleixner <hidden>
Date: 2008-06-17 07:17:17
Also in:
linux-acpi, lkml
Subsystem:
the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
On Tue, 17 Jun 2008, Rafael J. Wysocki wrote:
BTW, with the C1E patches reverted I don't get the WARNING: at /home/rafael/src/linux-next/kernel/smp.c:215 smp_call_function_single+0x3d/0xa2 in the log. Thomas?
Yeah, my bad. Fix below. Thanks, tglx -------------------> Subject: x86: c1e_idle, run BROADCAST_FORCE notify with irqs enabled From: Thomas Gleixner <redacted> Date: Tue, 17 Jun 2008 09:07:53 +0200 The BROADCAST_FORCE notification uses smp_function_call and therefor must be run with interrupts enabled. While at it, add a comment for the BROADCAST_EXIT notifier as well. Signed-off-by: Thomas Gleixner <redacted> ---
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 57fa86d..1450e0f 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c@@ -267,17 +267,29 @@ static void c1e_idle(void) if (!cpu_isset(cpu, c1e_mask)) { cpu_set(cpu, c1e_mask); - /* Force broadcast so ACPI can not interfere */ + /* + * Force broadcast so ACPI can not interfere. Needs + * to run with interrupts enabled as it uses + * smp_function_call. + */ + local_irq_enable(); clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_FORCE, &cpu); printk(KERN_INFO "Switch to broadcast mode on CPU%d\n", cpu); + local_irq_disable(); } clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &cpu); + default_idle(); - local_irq_disable(); - clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &cpu); - local_irq_enable(); + + /* + * The switch back from broadcast mode needs to be + * called with interrupts disabled. + */ + local_irq_disable(); + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &cpu); + local_irq_enable(); } else default_idle(); }