Commit 1c17f4d6 authored Jan 30, 2008 by Huang, Ying Committed by Ingo Molnar Jan 30, 2008

x86: ioremap_nocache fix



This patch fixes a bug of ioremap_nocache. ioremap_nocache() will call
__ioremap() with flags != 0 to do the real work, which will call
change_page_attr_addr() if phys_addr + size - 1 < (end_pfn_map << PAGE_SHIFT).
But some pages between 0 ~ end_pfn_map << PAGE_SHIFT are not mapped by
identity map, this will make change_page_attr_addr failed.

This patch is based on latest x86 git and has been tested on x86_64 platform.

Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

parent d2e626f4

arch/x86/mm/ioremap_64.c

+7 −0

Original line number	Diff line number	Diff line
		@@ -41,7 +41,14 @@ ioremap_change_attr(unsigned long phys_addr, unsigned long size,
		if (phys_addr + size - 1 < (end_pfn_map << PAGE_SHIFT)) {
		unsigned long npages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
		unsigned long vaddr = (unsigned long) __va(phys_addr);
		int level;

		/*
		* If there is no identity map for this address,
		* change_page_attr_addr is unnecessary
		*/
		if (!lookup_address(vaddr, &level))
		return err;
		/*
		* Must use a address here and not struct page because the phys addr
		* can be a in hole between nodes and not have an memmap entry.