[PATCH] mm: nobootmem: Correct alloc_bootmem semantics.

From: David Miller
Date: Wed Apr 25 2012 - 16:10:55 EST



The comments above __alloc_bootmem_node() claim that the code will
first try the allocation using 'goal' and if that fails it will
try again but with the 'goal' requirement dropped.

Unfortunately, this is not what the code does, so fix it to do so.

This is important for nobootmem conversions to architectures such
as sparc where MAX_DMA_ADDRESS is infinity.

On such architectures all of the allocations done by generic spots,
such as the sparse-vmemmap implementation, will pass in:

__pa(MAX_DMA_ADDRESS)

as the goal, and with the limit given as "-1" this will always fail
unless we add the appropriate fallback logic here.

Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>

diff --git a/mm/nobootmem.c b/mm/nobootmem.c
index 24f0fc1..e53bb8a 100644
--- a/mm/nobootmem.c
+++ b/mm/nobootmem.c
@@ -298,13 +298,19 @@ void * __init __alloc_bootmem_node(pg_data_t *pgdat, unsigned long size,
if (WARN_ON_ONCE(slab_is_available()))
return kzalloc_node(size, GFP_NOWAIT, pgdat->node_id);

+again:
ptr = __alloc_memory_core_early(pgdat->node_id, size, align,
goal, -1ULL);
if (ptr)
return ptr;

- return __alloc_memory_core_early(MAX_NUMNODES, size, align,
- goal, -1ULL);
+ ptr = __alloc_memory_core_early(MAX_NUMNODES, size, align,
+ goal, -1ULL);
+ if (!ptr && goal) {
+ goal = 0;
+ goto again;
+ }
+ return ptr;
}

void * __init __alloc_bootmem_node_high(pg_data_t *pgdat, unsigned long size,
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/