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Commit 3260e529 authored by Michael Bohan's avatar Michael Bohan Committed by Daniel Walker
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arm: mm: Don't free prohibited memmap entries 



The VM subsystem assumes that there are valid memmap entries to
the bank end aligned to MAX_ORDER_NR_PAGES. It will try and read
these page structs, and so we cannot free any memmap entries that
it may inspect.

Signed-off-by: default avatarMichael Bohan <mbohan@codeaurora.org>
Signed-off-by: default avatarDaniel Walker <dwalker@codeaurora.org>
parent 923a081c

arch/arm/mm/init.c

+9 −10
Original line number Diff line number Diff line
@@ -495,28 +495,27 @@ static void __init free_unused_memmap_node(int node, struct meminfo *mi) 
	unsigned int i;



	/*

	 * [FIXME] This relies on each bank being in address order.  This

	 * may not be the case, especially if the user has provided the

	 * information on the command line.

	 * This relies on each bank being in address order.

	 * The banks are sorted previously in bootmem_init().

	 */

	for_each_nodebank(i, mi, node) {

		struct membank *bank = &mi->bank[i];



		bank_start = bank_pfn_start(bank);

		if (bank_start < prev_bank_end) {

			printk(KERN_ERR "MEM: unordered memory banks.  "

				"Not freeing memmap.\n");

			break;

		}



		/*

		 * If we had a previous bank, and there is a space

		 * between the current bank and the previous, free it.

		 */

		if (prev_bank_end && prev_bank_end != bank_start)

		if (prev_bank_end && prev_bank_end < bank_start)

			free_memmap(node, prev_bank_end, bank_start);



		prev_bank_end = bank_pfn_end(bank);

		/*

		 * Align up here since the VM subsystem insists that the

		 * memmap entries are valid from the bank end aligned to

		 * MAX_ORDER_NR_PAGES.

		 */

		prev_bank_end = ALIGN(bank_pfn_end(bank), MAX_ORDER_NR_PAGES);

	}

}