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SubjectRe: [PATCH] m68k/mm: Stop printing the virtual memory layout
Hi Finn,

On Tue, Feb 13, 2018 at 1:48 AM, Finn Thain <fthain@telegraphics.com.au> wrote:
> On Mon, 12 Feb 2018, Geert Uytterhoeven wrote:
>> Since commit ad67b74d2469d9b8 ("printk: hash addresses printed with
>> %p"), the virtual memory layout printed during boot up contains "ptrval"
>> instead of actual addresses:
>>
>> Memory: 268040K/276480K available (2979K kernel code, 310K rwdata, 784K rodata, 144K init, 172K bss, 8440K reserved, 0K cma-reserved)
>> Virtual kernel memory layout:
>> vector : 0x003d2e74 - 0x003d3274 ( 1 KiB)
>> kmap : 0xd0000000 - 0xf0000000 ( 512 MiB)
>> vmalloc : 0x11800000 - 0xd0000000 (3048 MiB)
>> lowmem : 0x00000000 - 0x11000000 ( 272 MiB)
>> .init : 0x(ptrval) - 0x(ptrval) ( 144 KiB)
>> .text : 0x(ptrval) - 0x(ptrval) (2980 KiB)
>> .data : 0x(ptrval) - 0x(ptrval) (1095 KiB)
>> .bss : 0x(ptrval) - 0x(ptrval) ( 173 KiB)
>>
>> Instead of changing the printing to "%px", and leaking virtual memory
>> layout information again,
>>
>> just remove the printing completely, cfr. e.g.
>> commit 071929dbdd865f77 ("arm64: Stop printing the virtual memory
>> layout").
>>
>> All interesting information (actual section sizes) is already printed by
>> mem_init_print_info() just above anyway.
>
> Or maybe revert to %lx with pr_debug instead of pr_notice. Just a thought;

(%px prints unhashed pointers, no need for %lx and cast)

> I don't have any preference.

Dynamic debug is hot these days, so that may be enabled by distros,
still leaking the info.

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds

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