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User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.10) Gecko/20050716 Firefox/1.0.6

Description of problem:
Note: The fix already exists in the upstream kernel (2.6.17) and the i386 version of the RHEL4 U4 kernel (2.6.9-40.EL)

When using the boot parameter acpi=noirq, the kernel hangs (aka does not panic) in smp_read_mpc when trying to read the ES7000 MPConfig table (which has been moved higher in memory by an new firmware release).


Version-Release number of selected component (if applicable):
kernel-2.6.9-40

How reproducible:
Always


Steps to Reproduce:
1. Load new ES7000 BIOS (not released yet)
2. Boot the ES7000 with the boot parameter acpi=noirq
3. Machine hangs

Actual Results:

Machine Hangs

Expected Results:
The machine should have booted.

Additional info:
This patch changes the code to pass a virtual address to smp_read_mpc instead of a physical address.  This code has been copied directly from the i386 branch and works.  Excuse any spacing issues in this patch, I am writing this bug on windDOwS.

---
--- linux-2.6.9-40.orig/arch/x86_64/kernel/mpparse.c	2006-08-02 11:07:23.000000000 -0400
+++ linux-2.6.9-40.fixed/arch/x86_64/kernel/mpparse.c	2006-08-02 11:49:17.000000000 -0400
@@ -563,7 +563,7 @@
 		 * Read the physical hardware table.  Anything here will
 		 * override the defaults.
 		 */
-		if (!smp_read_mpc((void *)(unsigned long)mpf->mpf_physptr)) {
+		if (!smp_read_mpc((void *)phys_to_virt(mpf->mpf_physptr))) {
 			smp_found_config = 0;
 			printk(KERN_ERR "BIOS bug, MP table errors detected!...\n");
 			printk(KERN_ERR "... disabling SMP support. (tell your hw vendor)\n");