Re: [PATCH] fix CONFIG_IO_STRICT_DEVMEM, do not enable by default

From: Dan Williams
Date: Wed Jan 20 2016 - 18:57:21 EST


On Wed, Jan 20, 2016 at 3:53 PM, Kees Cook <keescook@xxxxxxxxxxxx> wrote:
> On Wed, Jan 20, 2016 at 3:48 PM, Dan Williams <dan.j.williams@xxxxxxxxx> wrote:
>> On Wed, Jan 20, 2016 at 3:12 PM, Kees Cook <keescook@xxxxxxxxxxxx> wrote:
>>> On Wed, Jan 20, 2016 at 2:37 PM, Dan Williams <dan.j.williams@xxxxxxxxx> wrote:
>>>> Larry reports: "My PowerBook G4 Aluminum with a 32-bit PPC processor
>>>> fails to boot for the 4.4-git series". This is likely due to X still
>>>> needing /dev/mem access on this platform.
>>>>
>>>> CONFIG_IO_STRICT_DEVMEM is not yet safe to turn on when
>>>> CONFIG_STRICT_DEVMEM=y. Remove the default so that old configurations
>>>> do not change behavior.
>>>>
>>>> Fixes: 90a545e98126 ("restrict /dev/mem to idle io memory ranges")
>>>> Reported-by: Larry Finger <Larry.Finger@xxxxxxxxxxxx>
>>>> Tested-by: Larry Finger <Larry.Finger@xxxxxxxxxxxx>
>>>> Link: http://marc.info/?l=linux-kernel&m=145332012023825&w=2
>>>> Cc: Arnd Bergmann <arnd@xxxxxxxx>
>>>> Cc: Ingo Molnar <mingo@xxxxxxxxxx>
>>>> Cc: Kees Cook <keescook@xxxxxxxxxxxx>
>>>> Cc: Russell King <linux@xxxxxxxxxxxxxxxx>
>>>> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
>>>> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
>>>> Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
>>>
>>> Acked-by: Kees Cook <keescook@xxxxxxxxxxxx>
>>>
>>
>> Thanks!
>>
>>> This should probably be CC: stable, yes?
>>
>> No, this breakage is new for the current merge window.
>
> Ah! Okay, I misunderstood the "4.4" comment. Should that be 4.5-git?

I believe Larry meant latest-Linus (v4.4.0+) when he said 4.4-git.