ARM: 7113/1: mm: Align bank start to MAX_ORDER_NR_PAGES

The VM subsystem assumes that there are valid memmap entries from
the bank start aligned to MAX_ORDER_NR_PAGES.

On the Ux500 we have a lot of mem=N arguments on the commandline
triggering this bug several times over and causing kernel
oops messages.

Cc: stable@kernel.org
Cc: Michael Bohan <mbohan@codeaurora.org>
Cc: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Johan Palsson <johan.palsson@stericsson.com>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c
index cc7e2d8be9aa6f55cd1f670c998e1c065acec75e..f8037ba338ac9dbc8b31cff97bd159375ae2c461 100644 (file)
--- a/arch/arm/mm/init.c
+++ b/arch/arm/mm/init.c
@@ -496,6 +496,13 @@ static void __init free_unused_memmap(struct meminfo *mi)
                 */
                bank_start = min(bank_start,
                                 ALIGN(prev_bank_end, PAGES_PER_SECTION));
+#else
+               /*
+                * Align down here since the VM subsystem insists that the
+                * memmap entries are valid from the bank start aligned to
+                * MAX_ORDER_NR_PAGES.
+                */
+               bank_start = round_down(bank_start, MAX_ORDER_NR_PAGES);
 #endif
                /*
                 * If we had a previous bank, and there is a space