The alignment mask is calculated incorrectly. Fixing the calculation
makes strange hangs/lockups disappear during the boot with Amstrad E3
and 3.6-rc1 kernel.
Signed-off-by: Aaro Koskinen <[email protected]>
---
arch/arm/mm/dma-mapping.c | 6 +++---
1 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index 2cc77b7..0e0466d 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -423,7 +423,7 @@ static void *__alloc_from_pool(size_t size, struct page **ret_page)
unsigned int pageno;
unsigned long flags;
void *ptr = NULL;
- size_t align;
+ unsigned long align_mask;
if (!pool->vaddr) {
WARN(1, "coherent pool not initialised!\n");
@@ -435,11 +435,11 @@ static void *__alloc_from_pool(size_t size, struct page **ret_page)
* small, so align them to their order in pages, minimum is a page
* size. This helps reduce fragmentation of the DMA space.
*/
- align = PAGE_SIZE << get_order(size);
+ align_mask = (1 << get_order(size)) - 1;
spin_lock_irqsave(&pool->lock, flags);
pageno = bitmap_find_next_zero_area(pool->bitmap, pool->nr_pages,
- 0, count, (1 << align) - 1);
+ 0, count, align_mask);
if (pageno < pool->nr_pages) {
bitmap_set(pool->bitmap, pageno, count);
ptr = pool->vaddr + PAGE_SIZE * pageno;
--
1.7.2.5
Hi Aaro,
On Sunday, August 05, 2012 7:32 PM Aaro Koskinen wrote:
> The alignment mask is calculated incorrectly. Fixing the calculation
> makes strange hangs/lockups disappear during the boot with Amstrad E3
> and 3.6-rc1 kernel.
>
> Signed-off-by: Aaro Koskinen <[email protected]>
Again, thanks for spotting and fixing the issue. I've applied it to my fixes branch.
I'm really sorry for introducing such stupid bugs together with my changes.
Best regards
--
Marek Szyprowski
Samsung Poland R&D Center