Re: [RFC 0/5] vmalloc_exec for modules and BPF programs

[Song Liu <songliubraving@fb.com>]

> 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