[PATCH bpf-next v3 0/5] bpf, x86: enable EXECMEM_ROX_CACHE for BPF allocations

["Mike Rapoport (Microsoft)" <rppt@kernel.org>]

Hi,

BPF allocations of executable memory on x86 are essentially read-only. Most
paths that call bpf_jit_alloc_exec() immediately make it ROX with
set_memory_rox().

The code generation, at least on x86, uses separately allocated writable
buffers and then updates the actual text memory with text_poke().

These patches do several small adjustments to how BPF allocates executable
memory and enable EXECMEM_ROX_CACHE for BPF allocations on x86.

---
v3 changes:
* replace vmalloc() with vzalloc() in bpf_dispatcher_change_prog()
* rebase on the current bpf-next

v2: https://patch.msgid.link/20260711-execmem-x86-rox-bpf-v0-v2-0-bfd956d35119@kernel.org
* rebase on the current bpf-next

v1: https://patch.msgid.link/20260626-execmem-x86-rox-bpf-v0-v1-0-45a0b0ed4fe9@kernel.org

---

---
Mike Rapoport (Microsoft) (5):
      bpf: dispatcher: allocate bpf_dispatcher->rw_image with vzalloc()
      bpf: drop __weak from bpf_jit_alloc_exec() and bpf_jit_free_exec()
      bpf: alloc_prog_pack(): skip ROX management for already ROX memory
      bpf, x86: make sure allocation in arch_bpf_trampoline_size() is writable
      x86/bpf: enable EXECMEM_ROX_CACHE for BPF allocations

 arch/x86/mm/init.c          |  4 ++--
 arch/x86/net/bpf_jit_comp.c |  5 ++---
 include/linux/filter.h      |  1 +
 kernel/bpf/core.c           | 30 +++++++++++++++++++++---------
 kernel/bpf/dispatcher.c     |  5 ++++-
 5 files changed, 30 insertions(+), 15 deletions(-)
---
base-commit: d1f4b56417a3dc1a0600f960b14f46bd25eda89d
change-id: 20260626-execmem-x86-rox-bpf-v0-b4241ade80df

--
Sincerely yours,
Mike.