From: Nicolas Pitre Date: Sun, 13 Sep 2015 02:25:26 +0000 (+0100) Subject: ARM: 8432/1: move VMALLOC_END from 0xff000000 to 0xff800000 X-Git-Tag: firefly_0821_release~176^2~840^2^3~17 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=6ff0966052c46efb53980b8a1add2e7b49c9f560;p=firefly-linux-kernel-4.4.55.git ARM: 8432/1: move VMALLOC_END from 0xff000000 to 0xff800000 There is a 12MB unused region in our memory map between the vmalloc and fixmap areas. This became unused with commit e9da6e9905e6, confirmed with commit 64d3b6a3f480. We also have a 8MB guard area before the vmalloc area. With the default 240MB vmalloc area size and the current VMALLOC_END definition, that means the end of low memory ends up at 0xef800000 which is unfortunate for 768MB machines where 8MB of RAM is lost to himem. Let's move VMALLOC_END to 0xff800000 so the guard area won't chop the top of the 768MB low memory area while keeping the default vmalloc area size unchanged and still preserving a gap between the vmalloc and fixmap areas. Signed-off-by: Nicolas Pitre Signed-off-by: Russell King --- diff --git a/Documentation/arm/memory.txt b/Documentation/arm/memory.txt index 4178ebda6e66..546a39048eb0 100644 --- a/Documentation/arm/memory.txt +++ b/Documentation/arm/memory.txt @@ -54,7 +54,7 @@ VMALLOC_START VMALLOC_END-1 vmalloc() / ioremap() space. located here through iotable_init(). VMALLOC_START is based upon the value of the high_memory variable, and VMALLOC_END - is equal to 0xff000000. + is equal to 0xff800000. PAGE_OFFSET high_memory-1 Kernel direct-mapped RAM region. This maps the platforms RAM, and typically diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h index f40354198bad..348caabb7625 100644 --- a/arch/arm/include/asm/pgtable.h +++ b/arch/arm/include/asm/pgtable.h @@ -43,7 +43,7 @@ */ #define VMALLOC_OFFSET (8*1024*1024) #define VMALLOC_START (((unsigned long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)) -#define VMALLOC_END 0xff000000UL +#define VMALLOC_END 0xff800000UL #define LIBRARY_TEXT_START 0x0c000000