[GIT PULL] x86/apic changes for v2.6.40

[GIT PULL] x86/apic changes for v2.6.40

[Ingo Molnar]

Linus,

Please pull the latest x86-apic-for-linus git tree from:

   git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip.git x86-apic-for-linus

 Thanks,

	Ingo

------------------>
Youquan Song (1):
      x86, apic: Print verbose error interrupt reason on apic=debug


 arch/x86/kernel/apic/apic.c |   41 ++++++++++++++++++++++++++---------------
 1 files changed, 26 insertions(+), 15 deletions(-)

diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index fabf01e..ae14712 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -1812,30 +1812,41 @@ void smp_spurious_interrupt(struct pt_regs *regs)
  */
 void smp_error_interrupt(struct pt_regs *regs)
 {
-	u32 v, v1;
+	u32 v0, v1;
+	u32 i = 0;
+	static const char * const error_interrupt_reason[] = {
+		"Send CS error",		/* APIC Error Bit 0 */
+		"Receive CS error",		/* APIC Error Bit 1 */
+		"Send accept error",		/* APIC Error Bit 2 */
+		"Receive accept error",		/* APIC Error Bit 3 */
+		"Redirectable IPI",		/* APIC Error Bit 4 */
+		"Send illegal vector",		/* APIC Error Bit 5 */
+		"Received illegal vector",	/* APIC Error Bit 6 */
+		"Illegal register address",	/* APIC Error Bit 7 */
+	};
 
 	exit_idle();
 	irq_enter();
 	/* First tickle the hardware, only then report what went on. -- REW */
-	v = apic_read(APIC_ESR);
+	v0 = apic_read(APIC_ESR);
 	apic_write(APIC_ESR, 0);
 	v1 = apic_read(APIC_ESR);
 	ack_APIC_irq();
 	atomic_inc(&irq_err_count);
 
-	/*
-	 * Here is what the APIC error bits mean:
-	 * 0: Send CS error
-	 * 1: Receive CS error
-	 * 2: Send accept error
-	 * 3: Receive accept error
-	 * 4: Reserved
-	 * 5: Send illegal vector
-	 * 6: Received illegal vector
-	 * 7: Illegal register address
-	 */
-	pr_debug("APIC error on CPU%d: %02x(%02x)\n",
-		smp_processor_id(), v , v1);
+	apic_printk(APIC_DEBUG, KERN_DEBUG "APIC error on CPU%d: %02x(%02x)",
+		    smp_processor_id(), v0 , v1);
+
+	v1 = v1 & 0xff;
+	while (v1) {
+		if (v1 & 0x1)
+			apic_printk(APIC_DEBUG, KERN_CONT " : %s", error_interrupt_reason[i]);
+		i++;
+		v1 >>= 1;
+	};
+
+	apic_printk(APIC_DEBUG, KERN_CONT "\n");
+
 	irq_exit();
 }