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Date:   Wed, 2 Aug 2023 13:41:30 +0300
From:   Dan Carpenter <dan.carpenter@linaro.org>
To:     Su Hui <suhui@nfschina.com>
Cc:     chuck.lever@oracle.com, jlayton@kernel.org, neilb@suse.de,
        kolga@netapp.com, Dai.Ngo@oracle.com, tom@talpey.com,
        trond.myklebust@hammerspace.com, anna@kernel.org,
        nathan@kernel.org, ndesaulniers@google.com, trix@redhat.com,
        bfields@fieldses.org, linux-nfs@vger.kernel.org,
        linux-kernel@vger.kernel.org, llvm@lists.linux.dev,
        kernel-janitors@vger.kernel.org
Subject: Re: [PATCH] fs: lockd: avoid possible wrong NULL parameter
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There was a big fight about memcpy() in 2010.

https://lwn.net/Articles/416821/

It's sort of related but also sort of different.  My understanding is
that the glibc memcpy() says that memcpy() always does a dereference so
it can delete all the NULL checks which come after.  The linux kernel
uses -fno-delete-null-pointer-checks to turn this behavior off.

regards,
dan carpenter