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Date:   Sat, 4 Apr 2020 02:31:05 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Daniel Borkmann <daniel@iogearbox.net>
Cc:     Christoph Hellwig <hch@infradead.org>,
        Alexei Starovoitov <ast@kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Masami Hiramatsu <mhiramat@kernel.org>, x86@kernel.org,
        linux-kernel@vger.kernel.org, bpf@vger.kernel.org,
        bgregg@netflix.com
Subject: Re: Question on "uaccess: Add strict non-pagefault kernel-space read
 function"
Message-ID: <20200404093105.GA445@infradead.org>
References: <20200403133533.GA3424@infradead.org>
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On Fri, Apr 03, 2020 at 04:20:24PM +0200, Daniel Borkmann wrote:
> With crazy old functions I presume you mean the old bpf_probe_read()
> which is mapped to BPF_FUNC_probe_read helper or something else entirely?

I couldn't care less about bpf, this is about the kernel API.

What I mean is that your new probe_kernel_read_strict and
strncpy_from_unsafe_strict helpers are good and useful.  But for this
to actually make sense we need to get rid of the non-strict versions,
and we also need to get rid of some of the weak alias magic.