On Mon, Oct 10, 2016 at 8:17 PM, Saeed Mahameed <sae...@dev.mellanox.co.il> wrote: > > > On Tuesday, October 11, 2016, Tom Herbert <t...@herbertland.com> wrote: >> >> On Mon, Oct 10, 2016 at 4:41 PM, Tom Herbert <t...@herbertland.com> wrote: >> > I am hitting this in mlx5 >> > >> > drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c: In function >> > ‘reclaim_pages_cmd.clone.0’: >> > drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c:346: error: call >> > to ‘__compiletime_assert_346’ declared with attribute error: >> > BUILD_BUG_ON failed: __mlx5_bit_off(manage_pages_out, pas[i]) % 64 >> > drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c: In function >> > ‘give_pages’: >> > drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c:291: error: call >> > to ‘__compiletime_assert_291’ declared with attribute error: >> > BUILD_BUG_ON failed: __mlx5_bit_off(manage_pages_in, pas[i]) % 64 >> > >> >> The expression in BUILD_BUG_ON expands to "((unsigned)(unsigned >> long)(&(((struct mlx5_ifc_manage_pages_in_bits *)0)->pas[i]))) % 64". >> The variable array index to pas makes this expression non-constant, I >> imagine that is where the problem lies. >> >> > Bisecting points to: >> > >> > commit a533ed5e179cd15512d40282617909d3482a771c >> > Author: Saeed Mahameed <sae...@mellanox.com> >> > Date: Sun Jul 17 13:27:25 2016 +0300 >> > >> > net/mlx5: Pages management commands via mlx5 ifc > > > Hi Tom, > We know about this issue, it happens only with gcc4.4 or gcc 4.2 i don't > remember exactly which. > Most likely it is a gcc issue. > I don't believe that is the case. As I pointed out this is giving BUILD_BUG_ON a non-constant expression. To fix this should just be a matter of using a constant argument for the BUILD_BUG_ON. AFAICT there's only two instances of MLX5_SET64 where this can be a problem. I will post a fix shortly.
Tom > Anyway, we are working on the issue and we will provide a fix or a W/A > hopefully next week. This week most of the team are on vacation. > > Thanks > Saeed.
