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From: Song Liu <song@kernel.org>
Date: Fri, 26 Apr 2024 11:50:24 -0700
Message-ID: <CAPhsuW6FZqYXvk4anxby8MccwejPPK5DNU-NGmg7_6T1XDU=Hg@mail.gmail.com>
Subject: Re: [PATCH v6 06/16] mm: introduce execmem_alloc() and execmem_free()
To: Mike Rapoport <rppt@kernel.org>
Cc: linux-kernel@vger.kernel.org, Alexandre Ghiti <alexghiti@rivosinc.com>, 
	Andrew Morton <akpm@linux-foundation.org>, =?UTF-8?B?QmrDtnJuIFTDtnBlbA==?= <bjorn@kernel.org>, 
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On Fri, Apr 26, 2024 at 1:30=E2=80=AFAM Mike Rapoport <rppt@kernel.org> wro=
te:
>
> From: "Mike Rapoport (IBM)" <rppt@kernel.org>
>
> module_alloc() is used everywhere as a mean to allocate memory for code.
>
> Beside being semantically wrong, this unnecessarily ties all subsystems
> that need to allocate code, such as ftrace, kprobes and BPF to modules an=
d
> puts the burden of code allocation to the modules code.
>
> Several architectures override module_alloc() because of various
> constraints where the executable memory can be located and this causes
> additional obstacles for improvements of code allocation.
>
> Start splitting code allocation from modules by introducing execmem_alloc=
()
> and execmem_free() APIs.
>
> Initially, execmem_alloc() is a wrapper for module_alloc() and
> execmem_free() is a replacement of module_memfree() to allow updating all
> call sites to use the new APIs.
>
> Since architectures define different restrictions on placement,
> permissions, alignment and other parameters for memory that can be used b=
y
> different subsystems that allocate executable memory, execmem_alloc() tak=
es
> a type argument, that will be used to identify the calling subsystem and =
to
> allow architectures define parameters for ranges suitable for that
> subsystem.
>
> No functional changes.
>
> Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>

Acked-by: Song Liu <song@kernel.org>