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Date:   Wed, 27 Jul 2022 15:31:39 +0300
From:   Leon Romanovsky <leon@kernel.org>
To:     Christoph Lameter <cl@gentwo.de>
Cc:     Bart Van Assche <bvanassche@acm.org>,
        Jason Gunthorpe <jgg@ziepe.ca>, linux-rdma@vger.kernel.org,
        Li Zhijian <lizhijian@fujitsu.com>,
        Hillf Danton <hdanton@sina.com>,
        Mike Christie <michael.christie@oracle.com>
Subject: Re: [PATCH 3/3] RDMA/srpt: Fix a use-after-free
Message-ID: <YuEwK35/xuNe24/G@unreal>
References: <20220726212156.1318010-1-bvanassche@acm.org>
 <20220726212156.1318010-4-bvanassche@acm.org>
 <YuEHOM/iGFEtaGde@unreal>
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On Wed, Jul 27, 2022 at 02:26:43PM +0200, Christoph Lameter wrote:
> On Wed, 27 Jul 2022, Leon Romanovsky wrote:
> 
> > Please no BUG_ON() in new code.
> 
> Do we now prefer NULL pointer dereferences causing bugs?

There are two possible scenarios.
1. "NULL can be in this flow." - In such case, the code should deal with
such flow and do not crash whole machine.
2. "NULL can't be in this flow." - Put WARN_ON() which serves as a
documentation/debug help to catch situations that are not possible.

Thanks

>