This is a note to let you know that I've just added the patch titled bus: mbus: fix window size calculation for 4GB windows to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: bus-mbus-fix-window-size-calculation-for-4gb-windows.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 2bbbd96357ce76cc45ec722c00f654aa7b189112 Mon Sep 17 00:00:00 2001 From: Jan Luebbe <jlu@xxxxxxxxxxxxxx> Date: Mon, 28 Aug 2017 17:25:16 +0200 Subject: bus: mbus: fix window size calculation for 4GB windows From: Jan Luebbe <jlu@xxxxxxxxxxxxxx> commit 2bbbd96357ce76cc45ec722c00f654aa7b189112 upstream. At least the Armada XP SoC supports 4GB on a single DRAM window. Because the size register values contain the actual size - 1, the MSB is set in that case. For example, the SDRAM window's control register's value is 0xffffffe1 for 4GB (bits 31 to 24 contain the size). The MBUS driver reads back each window's size from registers and calculates the actual size as (control_reg | ~DDR_SIZE_MASK) + 1, which overflows for 32 bit values, resulting in other miscalculations further on (a bad RAM window for the CESA crypto engine calculated by mvebu_mbus_setup_cpu_target_nooverlap() in my case). This patch changes the type in 'struct mbus_dram_window' from u32 to u64, which allows us to keep using the same register calculation code in most MBUS-using drivers (which calculate ->size - 1 again). Fixes: fddddb52a6c4 ("bus: introduce an Marvell EBU MBus driver") Signed-off-by: Jan Luebbe <jlu@xxxxxxxxxxxxxx> Signed-off-by: Gregory CLEMENT <gregory.clement@xxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/bus/mvebu-mbus.c | 2 +- include/linux/mbus.h | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) --- a/drivers/bus/mvebu-mbus.c +++ b/drivers/bus/mvebu-mbus.c @@ -720,7 +720,7 @@ mvebu_mbus_default_setup_cpu_target(stru if (mbus->hw_io_coherency) w->mbus_attr |= ATTR_HW_COHERENCY; w->base = base & DDR_BASE_CS_LOW_MASK; - w->size = (size | ~DDR_SIZE_MASK) + 1; + w->size = (u64)(size | ~DDR_SIZE_MASK) + 1; } } mvebu_mbus_dram_info.num_cs = cs; --- a/include/linux/mbus.h +++ b/include/linux/mbus.h @@ -29,8 +29,8 @@ struct mbus_dram_target_info struct mbus_dram_window { u8 cs_index; u8 mbus_attr; - u32 base; - u32 size; + u64 base; + u64 size; } cs[4]; }; Patches currently in stable-queue which might be from jlu@xxxxxxxxxxxxxx are queue-4.4/bus-mbus-fix-window-size-calculation-for-4gb-windows.patch