Fwd: patch for linux-2.6.30/arch/x86_64/mm/init.c

[jing zhang <zj.barak@gmail.com>]

hi,

I have no way sending to Andi Kleen, then try Mr. linux-kernel and Mr.
Ingo Molnar.

btw, AC's mailbox @ suse closed, and why?

thank you

---------- Forwarded message ----------
From: jing zhang <zj.barak@gmail.com>
Date: Sun, 21 Jun 2009 14:15:09 +0800
Subject: patch for linux-2.6.30/arch/x86_64/mm/init.c
To: ak@suse.de

Good Sunday Mr. Andi Kleen,

It seems that in function
    unsigned long __init_refok
    init_memory_mapping(unsigned long start, unsigned long end)

CONFIG_DEBUG_PAGEALLOC conflicts with use_pse and use_gbpages when
CONFIG_X86_32 also defined.

The following is my patch to you,

best

look forwar to your opion.
zj

//<<<<<<<<<<<<<<<<<<<<<

#ifdef CONFIG_DEBUG_PAGEALLOC
	/*
	 * For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages.
	 * This will simplify cpa(), which otherwise needs to support splitting
	 * large pages into small in interrupt context, etc.
	 */
	use_pse = use_gbpages = 0;
#else
	use_pse = cpu_has_pse;
	use_gbpages = direct_gbpages;
#endif

#ifdef CONFIG_X86_32
#ifdef CONFIG_X86_PAE
	set_nx();
	if (nx_enabled)
		printk(KERN_INFO "NX (Execute Disable) protection: active\n");
#endif
	/* Enable PSE if available */
-	if (cpu_has_pse)
+	/* and #ifdef CONFIG_DEBUG_PAGEALLOC */
+	if (cpu_has_pse && use_pse)
		set_in_cr4(X86_CR4_PSE);

	/* Enable PGE if available */
-	if (cpu_has_pge) {
+	/* and #ifdef CONFIG_DEBUG_PAGEALLOC */
+	if (cpu_has_pge && use_gbpages) {
		set_in_cr4(X86_CR4_PGE);
		__supported_pte_mask |= _PAGE_GLOBAL;
	}
#endif /* CONFIG_X86_32 */

//<<<<<<<<<<<<<<<<<<<<<