On 9/13/22 6:27 PM, Xu Kuohai wrote:
This series adds ftrace direct call for arm64, which is required to attach bpf trampoline to fentry. Although there is no agreement on how to support ftrace direct call on arm64, no patch has been posted except the one I posted in [1], so this series continues the work of [1] with the addition of long jump support. Now ftrace direct call works regardless of the distance between the callsite and custom trampoline. [1] https://lore.kernel.org/bpf/20220518131638.3401509-2-xukuohai@xxxxxxxxxx/ v2: - Fix compile and runtime errors caused by ftrace_rec_arch_init v1: https://lore.kernel.org/bpf/20220913063146.74750-1-xukuohai@xxxxxxxxxxxxxxx/ Xu Kuohai (4): ftrace: Allow users to disable ftrace direct call arm64: ftrace: Support long jump for ftrace direct call arm64: ftrace: Add ftrace direct call support ftrace: Fix dead loop caused by direct call in ftrace selftest
Given there's just a tiny fraction touching BPF JIT and most are around core arm64, it probably makes sense that this series goes via Catalin/Will through arm64 tree instead of bpf-next if it looks good to them. Catalin/Will, thoughts (Ack + bpf-next could work too, but I'd presume this just results in merge conflicts)?
arch/arm64/Kconfig | 2 + arch/arm64/Makefile | 4 + arch/arm64/include/asm/ftrace.h | 35 ++++-- arch/arm64/include/asm/patching.h | 2 + arch/arm64/include/asm/ptrace.h | 6 +- arch/arm64/kernel/asm-offsets.c | 1 + arch/arm64/kernel/entry-ftrace.S | 39 ++++-- arch/arm64/kernel/ftrace.c | 198 ++++++++++++++++++++++++++++-- arch/arm64/kernel/patching.c | 14 +++ arch/arm64/net/bpf_jit_comp.c | 4 + include/linux/ftrace.h | 2 + kernel/trace/Kconfig | 7 +- kernel/trace/ftrace.c | 9 +- kernel/trace/trace_selftest.c | 2 + 14 files changed, 296 insertions(+), 29 deletions(-)
Thanks, Daniel
