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* [PATCH v2] iommu-common: Do not use 64 bit  constant 0xffffffffffffffffl for computing align_mask
@ 2015-07-21  4:49 Sowmini Varadhan
  2015-07-21 19:59 ` Guenter Roeck
  0 siblings, 1 reply; 2+ messages in thread
From: Sowmini Varadhan @ 2015-07-21  4:49 UTC (permalink / raw)
  To: linux-kernel; +Cc: akpm, benh, davem, linux, linux, sowmini.varadhan

Using a 64 bit constant generates "warning: integer constant is too
large for 'long' type" on 32 bit platforms. Instead use ~0ul and
BITS_PER_LONG.

Detected by Andrew Morton on ARMD.

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
---
v2: use BITS_PER_LONG and ulong as discussed on mailing list.

 lib/iommu-common.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/lib/iommu-common.c b/lib/iommu-common.c
index df30632..ff19f66 100644
--- a/lib/iommu-common.c
+++ b/lib/iommu-common.c
@@ -119,7 +119,7 @@ unsigned long iommu_tbl_range_alloc(struct device *dev,
 	unsigned long align_mask = 0;
 
 	if (align_order > 0)
-		align_mask = 0xffffffffffffffffl >> (64 - align_order);
+		align_mask = ~0ul >> (BITS_PER_LONG - align_order);
 
 	/* Sanity check */
 	if (unlikely(npages == 0)) {
-- 
1.7.1


^ permalink raw reply related	[flat|nested] 2+ messages in thread

* Re: [PATCH v2] iommu-common: Do not use 64 bit  constant 0xffffffffffffffffl for computing align_mask
  2015-07-21  4:49 [PATCH v2] iommu-common: Do not use 64 bit constant 0xffffffffffffffffl for computing align_mask Sowmini Varadhan
@ 2015-07-21 19:59 ` Guenter Roeck
  0 siblings, 0 replies; 2+ messages in thread
From: Guenter Roeck @ 2015-07-21 19:59 UTC (permalink / raw)
  To: Sowmini Varadhan; +Cc: linux-kernel, akpm, benh, davem, linux

On Tue, Jul 21, 2015 at 06:49:41AM +0200, Sowmini Varadhan wrote:
> Using a 64 bit constant generates "warning: integer constant is too
> large for 'long' type" on 32 bit platforms. Instead use ~0ul and
> BITS_PER_LONG.
> 
> Detected by Andrew Morton on ARMD.
> 
> Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>

Looks ok afaics.

Reviewed-by: Guenter Roeck <linux@roeck-us.net>

> ---
> v2: use BITS_PER_LONG and ulong as discussed on mailing list.
> 
>  lib/iommu-common.c |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
> 
> diff --git a/lib/iommu-common.c b/lib/iommu-common.c
> index df30632..ff19f66 100644
> --- a/lib/iommu-common.c
> +++ b/lib/iommu-common.c
> @@ -119,7 +119,7 @@ unsigned long iommu_tbl_range_alloc(struct device *dev,
>  	unsigned long align_mask = 0;
>  
>  	if (align_order > 0)
> -		align_mask = 0xffffffffffffffffl >> (64 - align_order);
> +		align_mask = ~0ul >> (BITS_PER_LONG - align_order);
>  
>  	/* Sanity check */
>  	if (unlikely(npages == 0)) {
> -- 
> 1.7.1
> 

^ permalink raw reply	[flat|nested] 2+ messages in thread

end of thread, other threads:[~2015-07-21 20:03 UTC | newest]

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2015-07-21  4:49 [PATCH v2] iommu-common: Do not use 64 bit constant 0xffffffffffffffffl for computing align_mask Sowmini Varadhan
2015-07-21 19:59 ` Guenter Roeck

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