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

[Song Liu <song@kernel.org>]

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/

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(-)

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2.30.2