Commit ee408c79 authored by Andi Kleen's avatar Andi Kleen Committed by Linus Torvalds
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[PATCH] x86_64: Don't try to put kernel page tables beyond ZONE_DMA32. 



For not fully explained reasons it broke mem=... on several setups.

Also minor cleanup.

Cc: axboe@suse.de

Signed-off-by: default avatarAndi Kleen <ak@suse.de>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 142a64a6

arch/x86_64/mm/init.c

+5 −13
Original line number Diff line number Diff line
@@ -262,19 +262,11 @@ static void __init find_early_table_space(unsigned long end) 
	tables = round_up(puds * sizeof(pud_t), PAGE_SIZE) +

		 round_up(pmds * sizeof(pmd_t), PAGE_SIZE);



	/* Put page tables beyond the DMA zones if possible.

	   RED-PEN might be better to spread them out more over

	   memory to avoid hotspots */

	if (end > MAX_DMA32_PFN<<PAGE_SHIFT)

		start = MAX_DMA32_PFN << PAGE_SHIFT;

	else if (end > MAX_DMA_PFN << PAGE_SHIFT)

		start = MAX_DMA_PFN << PAGE_SHIFT;

	else

 	/* RED-PEN putting page tables only on node 0 could

 	   cause a hotspot and fill up ZONE_DMA. The page tables

 	   need roughly 0.5KB per GB. */

 	start = 0x8000;



 	table_start = find_e820_area(start, end, tables);

	if (table_start == -1)

		table_start = find_e820_area(0x8000, end, tables);

	if (table_start == -1UL)

		panic("Cannot find space for the kernel page tables");