* [net-next PATCH 1/2] mlxsw: spectrum_kvdl: use div_u64() for 64-bit division
@ 2018-02-23 13:15 Arnd Bergmann
2018-02-23 13:15 ` [net-next PATCH 2/2] mlxsw: spectrum_kvdl: avoid uninitialized variable warning Arnd Bergmann
` (2 more replies)
0 siblings, 3 replies; 6+ messages in thread
From: Arnd Bergmann @ 2018-02-23 13:15 UTC (permalink / raw)
To: Arkadi Sharshevsky, Jiri Pirko, Ido Schimmel
Cc: Arnd Bergmann, David S. Miller, Wei Yongjun, netdev, linux-kernel
Calculating the number of entries now uses 64-bit arithmetic that
causes a link error on 32-bit architectures:
drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.o: In function `mlxsw_sp_kvdl_init':
spectrum_kvdl.c:(.text+0x51c): undefined reference to `__aeabi_uldivmod'
We could probably use a 32-bit division here as before, but since this is
not in a performance critical path, div_u64() seems cleaner here.
Fixes: 887839e6960d ("mlxsw: spectrum_kvdl: Add support for dynamic partition set")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.c
index d27fa57ad3c3..6fd701db90c9 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.c
@@ -278,7 +278,7 @@ static int mlxsw_sp_kvdl_part_init(struct mlxsw_sp *mlxsw_sp,
resource_size = info->end_index - info->start_index + 1;
}
- nr_entries = resource_size / info->alloc_size;
+ nr_entries = div_u64(resource_size, info->alloc_size);
usage_size = BITS_TO_LONGS(nr_entries) * sizeof(unsigned long);
part = kzalloc(sizeof(*part) + usage_size, GFP_KERNEL);
if (!part)
--
2.9.0
^ permalink raw reply related [flat|nested] 6+ messages in thread* [net-next PATCH 2/2] mlxsw: spectrum_kvdl: avoid uninitialized variable warning
2018-02-23 13:15 [net-next PATCH 1/2] mlxsw: spectrum_kvdl: use div_u64() for 64-bit division Arnd Bergmann
@ 2018-02-23 13:15 ` Arnd Bergmann
2018-02-25 10:04 ` Arkadi Sharshevsky
2018-02-26 16:33 ` David Miller
2018-02-25 10:04 ` [net-next PATCH 1/2] mlxsw: spectrum_kvdl: use div_u64() for 64-bit division Arkadi Sharshevsky
2018-02-26 16:33 ` David Miller
2 siblings, 2 replies; 6+ messages in thread
From: Arnd Bergmann @ 2018-02-23 13:15 UTC (permalink / raw)
To: Arkadi Sharshevsky, Jiri Pirko, Ido Schimmel
Cc: Arnd Bergmann, David S. Miller, Wei Yongjun, netdev, linux-kernel
gcc warns that 'resource_id' is not initialized if we don't come though
any of the three 'case' statements before:
drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.c: In function 'mlxsw_sp_kvdl_part_init':
drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.c:275:8: error: 'resource_id' may be used uninitialized in this function [-Werror=maybe-uninitialized]
In the current code, that won't happen, but it's more robust to explicitly
handle this by returning a failure from mlxsw_sp_kvdl_part_init.
Fixes: 887839e6960d ("mlxsw: spectrum_kvdl: Add support for dynamic partition set")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.c
index 6fd701db90c9..059eb3214328 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.c
@@ -270,6 +270,8 @@ static int mlxsw_sp_kvdl_part_init(struct mlxsw_sp *mlxsw_sp,
case MLXSW_SP_KVDL_PART_LARGE_CHUNKS:
resource_id = MLXSW_SP_RESOURCE_KVD_LINEAR_LARGE_CHUNKS;
break;
+ default:
+ return -EINVAL;
}
err = devlink_resource_size_get(devlink, resource_id, &resource_size);
--
2.9.0
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [net-next PATCH 2/2] mlxsw: spectrum_kvdl: avoid uninitialized variable warning
2018-02-23 13:15 ` [net-next PATCH 2/2] mlxsw: spectrum_kvdl: avoid uninitialized variable warning Arnd Bergmann
@ 2018-02-25 10:04 ` Arkadi Sharshevsky
2018-02-26 16:33 ` David Miller
1 sibling, 0 replies; 6+ messages in thread
From: Arkadi Sharshevsky @ 2018-02-25 10:04 UTC (permalink / raw)
To: Arnd Bergmann, Jiri Pirko, Ido Schimmel
Cc: David S. Miller, Wei Yongjun, netdev, linux-kernel
On 02/23/2018 03:15 PM, Arnd Bergmann wrote:
> gcc warns that 'resource_id' is not initialized if we don't come though
> any of the three 'case' statements before:
>
> drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.c: In function 'mlxsw_sp_kvdl_part_init':
> drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.c:275:8: error: 'resource_id' may be used uninitialized in this function [-Werror=maybe-uninitialized]
>
> In the current code, that won't happen, but it's more robust to explicitly
> handle this by returning a failure from mlxsw_sp_kvdl_part_init.
>
> Fixes: 887839e6960d ("mlxsw: spectrum_kvdl: Add support for dynamic partition set")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
> drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.c
> index 6fd701db90c9..059eb3214328 100644
> --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.c
> +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.c
> @@ -270,6 +270,8 @@ static int mlxsw_sp_kvdl_part_init(struct mlxsw_sp *mlxsw_sp,
> case MLXSW_SP_KVDL_PART_LARGE_CHUNKS:
> resource_id = MLXSW_SP_RESOURCE_KVD_LINEAR_LARGE_CHUNKS;
> break;
> + default:
> + return -EINVAL;
> }
>
> err = devlink_resource_size_get(devlink, resource_id, &resource_size);
>
Acked-by: Arkadi Sharshevsky <arkadis@mellanox.com>
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [net-next PATCH 2/2] mlxsw: spectrum_kvdl: avoid uninitialized variable warning
2018-02-23 13:15 ` [net-next PATCH 2/2] mlxsw: spectrum_kvdl: avoid uninitialized variable warning Arnd Bergmann
2018-02-25 10:04 ` Arkadi Sharshevsky
@ 2018-02-26 16:33 ` David Miller
1 sibling, 0 replies; 6+ messages in thread
From: David Miller @ 2018-02-26 16:33 UTC (permalink / raw)
To: arnd; +Cc: arkadis, jiri, idosch, weiyongjun1, netdev, linux-kernel
From: Arnd Bergmann <arnd@arndb.de>
Date: Fri, 23 Feb 2018 14:15:32 +0100
> gcc warns that 'resource_id' is not initialized if we don't come though
> any of the three 'case' statements before:
>
> drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.c: In function 'mlxsw_sp_kvdl_part_init':
> drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.c:275:8: error: 'resource_id' may be used uninitialized in this function [-Werror=maybe-uninitialized]
>
> In the current code, that won't happen, but it's more robust to explicitly
> handle this by returning a failure from mlxsw_sp_kvdl_part_init.
>
> Fixes: 887839e6960d ("mlxsw: spectrum_kvdl: Add support for dynamic partition set")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Applied.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [net-next PATCH 1/2] mlxsw: spectrum_kvdl: use div_u64() for 64-bit division
2018-02-23 13:15 [net-next PATCH 1/2] mlxsw: spectrum_kvdl: use div_u64() for 64-bit division Arnd Bergmann
2018-02-23 13:15 ` [net-next PATCH 2/2] mlxsw: spectrum_kvdl: avoid uninitialized variable warning Arnd Bergmann
@ 2018-02-25 10:04 ` Arkadi Sharshevsky
2018-02-26 16:33 ` David Miller
2 siblings, 0 replies; 6+ messages in thread
From: Arkadi Sharshevsky @ 2018-02-25 10:04 UTC (permalink / raw)
To: Arnd Bergmann, Jiri Pirko, Ido Schimmel
Cc: David S. Miller, Wei Yongjun, netdev, linux-kernel
On 02/23/2018 03:15 PM, Arnd Bergmann wrote:
> Calculating the number of entries now uses 64-bit arithmetic that
> causes a link error on 32-bit architectures:
>
> drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.o: In function `mlxsw_sp_kvdl_init':
> spectrum_kvdl.c:(.text+0x51c): undefined reference to `__aeabi_uldivmod'
>
> We could probably use a 32-bit division here as before, but since this is
> not in a performance critical path, div_u64() seems cleaner here.
>
> Fixes: 887839e6960d ("mlxsw: spectrum_kvdl: Add support for dynamic partition set")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
> drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.c
> index d27fa57ad3c3..6fd701db90c9 100644
> --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.c
> +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.c
> @@ -278,7 +278,7 @@ static int mlxsw_sp_kvdl_part_init(struct mlxsw_sp *mlxsw_sp,
> resource_size = info->end_index - info->start_index + 1;
> }
>
> - nr_entries = resource_size / info->alloc_size;
> + nr_entries = div_u64(resource_size, info->alloc_size);
> usage_size = BITS_TO_LONGS(nr_entries) * sizeof(unsigned long);
> part = kzalloc(sizeof(*part) + usage_size, GFP_KERNEL);
> if (!part)
>
Acked-by: Arkadi Sharshevsky <arkadis@mellanox.com>
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [net-next PATCH 1/2] mlxsw: spectrum_kvdl: use div_u64() for 64-bit division
2018-02-23 13:15 [net-next PATCH 1/2] mlxsw: spectrum_kvdl: use div_u64() for 64-bit division Arnd Bergmann
2018-02-23 13:15 ` [net-next PATCH 2/2] mlxsw: spectrum_kvdl: avoid uninitialized variable warning Arnd Bergmann
2018-02-25 10:04 ` [net-next PATCH 1/2] mlxsw: spectrum_kvdl: use div_u64() for 64-bit division Arkadi Sharshevsky
@ 2018-02-26 16:33 ` David Miller
2 siblings, 0 replies; 6+ messages in thread
From: David Miller @ 2018-02-26 16:33 UTC (permalink / raw)
To: arnd; +Cc: arkadis, jiri, idosch, weiyongjun1, netdev, linux-kernel
From: Arnd Bergmann <arnd@arndb.de>
Date: Fri, 23 Feb 2018 14:15:31 +0100
> Calculating the number of entries now uses 64-bit arithmetic that
> causes a link error on 32-bit architectures:
>
> drivers/net/ethernet/mellanox/mlxsw/spectrum_kvdl.o: In function `mlxsw_sp_kvdl_init':
> spectrum_kvdl.c:(.text+0x51c): undefined reference to `__aeabi_uldivmod'
>
> We could probably use a 32-bit division here as before, but since this is
> not in a performance critical path, div_u64() seems cleaner here.
>
> Fixes: 887839e6960d ("mlxsw: spectrum_kvdl: Add support for dynamic partition set")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Applied.
^ permalink raw reply [flat|nested] 6+ messages in thread
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2018-02-23 13:15 [net-next PATCH 1/2] mlxsw: spectrum_kvdl: use div_u64() for 64-bit division Arnd Bergmann
2018-02-23 13:15 ` [net-next PATCH 2/2] mlxsw: spectrum_kvdl: avoid uninitialized variable warning Arnd Bergmann
2018-02-25 10:04 ` Arkadi Sharshevsky
2018-02-26 16:33 ` David Miller
2018-02-25 10:04 ` [net-next PATCH 1/2] mlxsw: spectrum_kvdl: use div_u64() for 64-bit division Arkadi Sharshevsky
2018-02-26 16:33 ` David Miller
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