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Date:   Wed, 18 Jan 2023 08:49:20 +0200
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Subject: Re: [PATCH] [v2] mlx5: reduce stack usage in mlx5_setup_tc
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To:     Arnd Bergmann <arnd@kernel.org>,
        Saeed Mahameed <saeedm@nvidia.com>,
        Leon Romanovsky <leon@kernel.org>
Cc:     Arnd Bergmann <arnd@arndb.de>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Nathan Chancellor <nathan@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Tom Rix <trix@redhat.com>, Tariq Toukan <tariqt@nvidia.com>,
        Maxim Mikityanskiy <maximmi@nvidia.com>,
        Gal Pressman <gal@nvidia.com>, Lama Kayal <lkayal@nvidia.com>,
        Moshe Tal <moshet@nvidia.com>, netdev@vger.kernel.org,
        linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org,
        llvm@lists.linux.dev
References: <20230117210324.1371169-1-arnd@kernel.org>
From:   Tariq Toukan <ttoukan.linux@gmail.com>
In-Reply-To: <20230117210324.1371169-1-arnd@kernel.org>
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On 17/01/2023 23:01, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@arndb.de>
> 
> Clang warns about excessive stack usage on 32-bit targets:
> 
> drivers/net/ethernet/mellanox/mlx5/core/en_main.c:3597:12: error: stack frame size (1184) exceeds limit (1024) in 'mlx5e_setup_tc' [-Werror,-Wframe-larger-than]
> static int mlx5e_setup_tc(struct net_device *dev, enum tc_setup_type type,
> 
> It turns out that both the mlx5e_setup_tc_mqprio_dcb() function and
> the mlx5e_safe_switch_params() function it calls have a copy of
> 'struct mlx5e_params' on the stack, and this structure is fairly
> large.
> 
> Use dynamic allocation for the inner one.
> 
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
> v2: simplify the patch
> ---
>   .../net/ethernet/mellanox/mlx5/core/en_main.c   | 17 +++++++++++------
>   1 file changed, 11 insertions(+), 6 deletions(-)
> 

Thanks for your patch.
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>