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From:   Arvind Sankar <nivedita@alum.mit.edu>
Date:   Sat, 29 Feb 2020 19:11:23 -0500
To:     Kees Cook <keescook@chromium.org>
Cc:     Arvind Sankar <nivedita@alum.mit.edu>, dave.hansen@linux.intel.com,
        kernel-hardening@lists.openwall.com, linux-kernel@vger.kernel.org,
        luto@kernel.org, me@tobin.cc, peterz@infradead.org, tycho@tycho.ws,
        x86@kernel.org
Subject: Re: [PATCH] x86/mm/init_32: Don't print out kernel memory layout if
 KASLR
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References: <20200226215039.2842351-1-nivedita@alum.mit.edu>
 <202002291534.ED372CC@keescook>
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On Sat, Feb 29, 2020 at 03:51:45PM -0800, Kees Cook wrote:
> Arvind Sankar said:
> > For security, only show the virtual kernel memory layout if KASLR is
> > disabled.
> 
> These have been entirely removed on other architectures, so let's
> just do the same for ia32 and remove it unconditionally.
> 
> 071929dbdd86 ("arm64: Stop printing the virtual memory layout")
> 1c31d4e96b8c ("ARM: 8820/1: mm: Stop printing the virtual memory layout")
> 31833332f798 ("m68k/mm: Stop printing the virtual memory layout")
> fd8d0ca25631 ("parisc: Hide virtual kernel memory layout")
> adb1fe9ae2ee ("mm/page_alloc: Remove kernel address exposure in free_reserved_area()")
> 
> -Kees
> 
> -- 
> Kees Cook

microblaze (arch/microblaze/mm/init.c) and PPC32 (arch/powerpc/mm/mem.c)
appear to still print it out. I can't test those, but will resubmit
x86-32 with it removed.