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From:   Song Liu <songliubraving@fb.com>
To:     Peter Zijlstra <peterz@infradead.org>
CC:     Linux-MM <linux-mm@kvack.org>, lkml <linux-kernel@vger.kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        X86 ML <x86@kernel.org>, Christoph Hellwig <hch@lst.de>,
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        "Edgecombe, Rick P" <rick.p.edgecombe@intel.com>,
        Luis Chamberlain <mcgrof@kernel.org>,
        Dave Hansen <dave.hansen@intel.com>, Song Liu <song@kernel.org>
Subject: Re: [RFC 0/5] vmalloc_exec for modules and BPF programs
Thread-Topic: [RFC 0/5] vmalloc_exec for modules and BPF programs
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Date:   Mon, 22 Aug 2022 15:46:38 +0000
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References: <20220818224218.2399791-1-song@kernel.org>
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> On Aug 18, 2022, at 3:42 PM, Song Liu <song@kernel.org> wrote:
> 
> This set is a prototype that allows dynamic kernel text (modules, bpf
> programs, various trampolines, etc.) to share huge pages. The idea is
> similar to Peter's suggestion in [1]. Please refer to each patch for
> more detais.
> 
> The ultimate goal is to only host kernel text in 2MB pages (for x86_64).
> 
> Please share your comments on this.
> 
> Thanks!
> 
> [1] https://lore.kernel.org/bpf/Ys6cWUMHO8XwyYgr@hirez.programming.kicks-ass.net/

Hi Peter, 

Could you please share your feedback on this? 

Thanks,
Song

PS: I guess vger dropped my patch again. :( The set is also available at

https://git.kernel.org/pub/scm/linux/kernel/git/song/linux.git 

branch vmalloc_exec. 

> 
> Song Liu (5):
>  vmalloc: introduce vmalloc_exec and vfree_exec
>  bpf: use vmalloc_exec
>  modules, x86: use vmalloc_exec for module core
>  vmalloc_exec: share a huge page with kernel text
>  vmalloc: vfree_exec: free unused vm_struct
> 
> arch/x86/Kconfig              |   1 +
> arch/x86/kernel/alternative.c |  30 ++++-
> arch/x86/kernel/module.c      |   1 +
> arch/x86/mm/init_64.c         |   3 +-
> include/linux/vmalloc.h       |  16 +--
> kernel/bpf/core.c             | 155 ++------------------------
> kernel/module/main.c          |  23 ++--
> kernel/module/strict_rwx.c    |   3 -
> kernel/trace/ftrace.c         |   3 +-
> mm/nommu.c                    |   7 ++
> mm/vmalloc.c                  | 200 +++++++++++++++++++++++++++++-----
> 11 files changed, 239 insertions(+), 203 deletions(-)
> 
> --
> 2.30.2