[PATCH 01/11] memblock: Don't adjust size in memblock_find_base()

Yinghai Lu
2011-02-07T23:52:20Z

While applying patch to use memblock to find aperture for 64bit x86.
Ingo found system with 1g + force_iommu

> No AGP bridge found
> Node 0: aperture @ 38000000 size 32 MB
> Aperture pointing to e820 RAM. Ignoring.
> Your BIOS doesn't leave a aperture memory hole
> Please enable the IOMMU option in the BIOS setup
> This costs you 64 MB of RAM
> Cannot allocate aperture memory hole (0,65536K)

the corresponding code:
addr = memblock_find_in_range(0, 1ULL<<32, aper_size, 512ULL<<20);
if (addr == MEMBLOCK_ERROR || addr + aper_size > 0xffffffff) {
printk(KERN_ERR
"Cannot allocate aperture memory hole (%lx,%uK)\n",
addr, aper_size>>10);
return 0;
}
memblock_x86_reserve_range(addr, addr + aper_size, "aperture64")

it failes because memblock core code align the size with 512M. that could make
size way too big.

So don't align the size in that case.

acctually __memblock_alloc_base, the another caller already align that before calling that function.

BTW. x86 does not use __memblock_alloc_base...

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
mm/memblock.c | 2 --
1 files changed, 0 insertions(+), 2 deletions(-)

diff --git a/mm/memblock.c b/mm/memblock.c
index bdba245..4618fda 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -137,8 +137,6 @@ static phys_addr_t __init_memblock memblock_find_base(phys_addr_t size,

BUG_ON(0 == size);

- size = memblock_align_up(size, align);
-
/* Pump up max_addr */
if (end == MEMBLOCK_ALLOC_ACCESSIBLE)
end = memblock.current_limit;
--
1.7.1