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Date: Tue, 11 Jun 2024 19:43:12 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Rafael Aquini <aquini@redhat.com>
Cc: linux-kernel@vger.kernel.org, Arnd Bergmann <arnd@arndb.de>, Heiko
 Carstens <hca@linux.ibm.com>, Petr Mladek <pmladek@suse.com>, Mike Rapoport
 <rppt@kernel.org>, Paul McKenney <paulmck@kernel.org>, Samuel Holland
 <samuel.holland@sifive.com>
Subject: Re: [PATCH v2] mm: mmap: allow for the maximum number of bits for
 randomizing mmap_base by default
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On Tue, 11 Jun 2024 21:35:24 -0400 Rafael Aquini <aquini@redhat.com> wrote:

> > Shouldn't we make this the default (at least for 32-bit) so the
> > regressed kernels are fixed simply by applying this patch?
> > 
> 
> That is a fair take, indeed. I guess we could do something like
> 
>  config FORCE_MAX_MMAP_RND_BITS
>         bool "Force maximum number of bits to use for ASLR of mmap base address"
> -       default n
> +       default y if !64BIT

"something like" != "exhaustively tested" ;)

I'll toss that in there, but please do let me know when it is suitable
for an upstream merge.

I also added cc:stable.