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Sender: Guenter Roeck <groeck7@gmail.com>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Richard Henderson <rth@twiddle.net>,
        Ivan Kokshaysky <ink@jurassic.park.msu.ru>,
        Matt Turner <mattst88@gmail.com>,
        "James E . J . Bottomley" <James.Bottomley@hansenpartnership.com>,
        Helge Deller <deller@gmx.de>,
        "David S . Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        alpha <linux-alpha@vger.kernel.org>,
        Geert Uytterhoeven <geert@linux-m68k.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-parisc@vger.kernel.org, Netdev <netdev@vger.kernel.org>,
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 <CAHk-=wjXr+NnNPTorhaW81eAbdF90foVo-5pQqRmXZi-ZGaX6Q@mail.gmail.com>
From:   Guenter Roeck <linux@roeck-us.net>
Subject: Re: [PATCH v2 0/4] Introduce and use absolute_pointer macro
Message-ID: <47fcc9cc-7d2e-bc79-122b-8eccfe00d8f3@roeck-us.net>
Date:   Wed, 15 Sep 2021 12:35:24 -0700
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On 9/15/21 12:18 PM, Linus Torvalds wrote:
> On Tue, Sep 14, 2021 at 8:52 PM Guenter Roeck <linux@roeck-us.net> wrote:
>>
>> This patch series introduces absolute_pointer() to fix the problem.
>> absolute_pointer() disassociates a pointer from its originating symbol
>> type and context, and thus prevents gcc from making assumptions about
>> pointers passed to memory operations.
> 
> Ok, I've applied this to my tree.
> 
> I note that the physical BOOT_PCB addresses in the alpha setup.h file
> might be useful for things like MILO in user space, but since I
> couldn't even find MILO sources any more, I couldn't really check.
> 
> I suspect alpha is basically on life support and presumably nobody
> would ever compile a bootloader anyway, so it's unlikely to matter.
> 
> If somebody does find any issues, we'll know better and we can ask
> where the user space sources are that might use that alpha setup.h
> file.
> 

FWIW, I did find a set of MILO sources. Search for milo-2.2-18.tar.bz2;
it points to a variety of gentoo mirrors.
That version does not reference BOOT_PCB. I thought about removing this
define as well as a couple of other unused defines, but wanted to keep
the changes minimal.

On a side note, we may revive the parisc patch. Helge isn't entirely
happy with the other solution for parisc; it is quite invasive and
touches a total of 19 files if I counted correctly.

Thanks,
Guenter