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Date: Mon, 19 Sep 2016 16:28:11 +0300
From: Leon Romanovsky <leon@kernel.org>
To: Arnd Bergmann <arnd@arndb.de>
Cc: Doug Ledford <dledford@redhat.com>, Sean Hefty <sean.hefty@intel.com>,
        Hal Rosenstock <hal.rosenstock@gmail.com>,
        Moni Shoua <monis@mellanox.com>, Yonatan Cohen <yonatanc@mellanox.com>,
        linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] IB/rxe: avoid putting a large struct rxe_qp on stack
Message-ID: <20160919132811.GI3273@leon.nu>
References: <20160919115826.553858-1-arnd@arndb.de>
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On Mon, Sep 19, 2016 at 01:57:26PM +0200, Arnd Bergmann wrote:
> A race condition fix added an rxe_qp structure to the stack in order
> to be able to perform rollback in rxe_requester(), but the structure
> is large enough to trigger the warning for possible stack overflow:
>
> drivers/infiniband/sw/rxe/rxe_req.c: In function 'rxe_requester':
> drivers/infiniband/sw/rxe/rxe_req.c:757:1: error: the frame size of 2064 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
>
> This changes the rollback function to only save the psn inside
> the qp, which is the only field we access in the rollback_qp
> anyway.
>
> Fixes: 3050b9985024 ("IB/rxe: Fix race condition between requester and completer")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Thanks Arnd,
It is much cleaner approach.
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>

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