Re: linux-next: build failure after merge of the net-next tree

Jakub Kicinski
2022-03-21T23:13:23Z

On Mon, 21 Mar 2022 18:39:41 +1100 Stephen Rothwell wrote:
> Hi all,
>
> After merging the net-next tree, today's linux-next build (x86_64
> allmodconfig) failed like this:
>
> In file included from include/linux/string.h:253,
> from include/linux/bitmap.h:11,
> from include/linux/cpumask.h:12,
> from arch/x86/include/asm/cpumask.h:5,
> from arch/x86/include/asm/msr.h:11,
> from arch/x86/include/asm/processor.h:22,
> from arch/x86/include/asm/timex.h:5,
> from include/linux/timex.h:65,
> from include/linux/time32.h:13,
> from include/linux/time.h:60,
> from include/linux/ktime.h:24,
> from include/linux/timer.h:6,
> from include/linux/netdevice.h:24,
> from include/trace/events/xdp.h:8,
> from include/linux/bpf_trace.h:5,
> from drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c:33:
> In function 'fortify_memset_chk',
> inlined from 'mlx5e_xmit_xdp_frame' at drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c:438:3:
> include/linux/fortify-string.h:242:25: error: call to '__write_overflow_field' declared with attribute warning: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Werror=attribute-warning]
> 242 | __write_overflow_field(p_size_field, size);
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> Caused by commit
>
> 9ded70fa1d81 ("net/mlx5e: Don't prefill WQEs in XDP SQ in the multi buffer mode")
>
> exposed by the kspp tree.
>
> I have applied the following fix patch for today (a better one is
> probably possible).

Hi Saeed,

thoughts?

Would be great to get this sorted by tomorrow.

> From: Stephen Rothwell <sfr@canb.auug.org.au>
> Date: Mon, 21 Mar 2022 18:29:24 +1100
> Subject: [PATCH] fxup for "net/mlx5e: Don't prefill WQEs in XDP SQ in the multi buffer mode"
>
> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
> ---
> drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c | 3 +--
> include/linux/mlx5/qp.h | 5 +++++
> 2 files changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c
> index f35b62ce4c07..8f321a6c0809 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c
> @@ -435,8 +435,7 @@ mlx5e_xmit_xdp_frame(struct mlx5e_xdpsq *sq, struct mlx5e_xmit_data *xdptxd,
> u8 num_pkts = 1 + num_frags;
> int i;
>
> - memset(&cseg->signature, 0, sizeof(*cseg) -
> - sizeof(cseg->opmod_idx_opcode) - sizeof(cseg->qpn_ds));
> + memset(&cseg->trailer, 0, sizeof(cseg->trailer));
> memset(eseg, 0, sizeof(*eseg) - sizeof(eseg->trailer));
>
> eseg->inline_hdr.sz = cpu_to_be16(inline_hdr_sz);
> diff --git a/include/linux/mlx5/qp.h b/include/linux/mlx5/qp.h
> index 61e48d459b23..8bda3ba5b109 100644
> --- a/include/linux/mlx5/qp.h
> +++ b/include/linux/mlx5/qp.h
> @@ -202,6 +202,9 @@ struct mlx5_wqe_fmr_seg {
> struct mlx5_wqe_ctrl_seg {
> __be32 opmod_idx_opcode;
> __be32 qpn_ds;
> +
> + struct_group(trailer,
> +
> u8 signature;
> u8 rsvd[2];
> u8 fm_ce_se;
> @@ -211,6 +214,8 @@ struct mlx5_wqe_ctrl_seg {
> __be32 umr_mkey;
> __be32 tis_tir_num;
> };
> +
> + ); /* end of trailer group */
> };
>
> #define MLX5_WQE_CTRL_DS_MASK 0x3f