linux-kernel - Re: [PATCH] m68knommu: fix undefined reference to `mach_get_rtc

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 16 May 2022 16:08:53 +1000
From:   Greg Ungerer <gerg@...ux-m68k.org>
To:     Arnd Bergmann <arnd@...db.de>
Cc:     Geert Uytterhoeven <geert@...ux-m68k.org>,
        Linux/m68k <linux-m68k@...r.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        kernel test robot <lkp@...el.com>
Subject: Re: [PATCH] m68knommu: fix undefined reference to `mach_get_rtc_pll'

Hi Arnd,

On 13/5/22 22:59, Arnd Bergmann wrote:
> On Fri, May 13, 2022 at 2:25 PM Greg Ungerer <gerg@...ux-m68k.org> wrote:
>> On 13/5/22 17:12, Geert Uytterhoeven wrote:
>>> read_persistent_clock64() uses mach_hwclk(), which is provided by
>>> both setup_mm.c and setup_no.c, so it's always available?> Albeit not populated by coldfire or nommu platform code, so I see
>>> the point in depending on MMU (no nommu Amiga support yet ;-).
>>
>> Yes, exactly. And even worse is that on ColdFire platforms it
>> is never set, so will be the startup value of NULL. It is called
>> without checking for NULL in both of rtc_generic_get_time() and
>> rtc_generic_set_time().
> 
> I think that's ok because rtc_generic_{get,set}_time is only called
> from the rtc_generic driver, but that is not registered when mach_hwclk()
> is NULL.
> 
> With your patch to add the CONFIG_MMU check, you can actually
> remove the mach_hwclk() symbol from setup_no.c, and move the
> remaining RTC related symbols from setup_mm.c into the #ifdef.

Yes, I think that would be a good idea.
Tidies thins up a little.

Regards
Greg