From: Mike Rapoport <rppt@kernel.org>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>,
linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] execmem: enforce allocation size aligment to PAGE_SIZE
Date: Thu, 24 Apr 2025 08:50:40 +0300 [thread overview]
Message-ID: <aAnRMGGaytI3ELMu@kernel.org> (raw)
In-Reply-To: <20250423143650.6595dcc7178351b62c31782c@linux-foundation.org>
On Wed, Apr 23, 2025 at 02:36:50PM -0700, Andrew Morton wrote:
> On Wed, 23 Apr 2025 17:48:07 +0300 Mike Rapoport <rppt@kernel.org> wrote:
>
> > Before introduction of ROX cache execmem allocation size was always
> > implicitly aligned to PAGE_SIZE inside vmalloc.
> >
> > However, when allocation happens from the ROX cache, this is not
> > enforced.
> >
> > Make sure that the allocation size is always consistently aligned to
> > PAGE_SIZE.
>
> Does this have any known runtime effect?
Right now it'll make the maple trees in execmem_cache more compact.
And it's a precaution for the case when execmem callers would want to
change permissions on unaligned range because that would WARN_ON() loudly.
--
Sincerely yours,
Mike.
next prev parent reply other threads:[~2025-04-24 5:50 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-04-23 14:48 Mike Rapoport
2025-04-23 14:56 ` Peter Zijlstra
2025-04-23 21:36 ` Andrew Morton
2025-04-24 5:50 ` Mike Rapoport [this message]
2025-04-24 8:53 ` Peter Zijlstra
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