| Message ID | 20211027085520.992974471@infradead.org (mailing list archive) |
|---|---|
| State | Not Applicable |
| Delegated to: | BPF |
| Headers | show |
| Series | x86: Rewrite the retpoline rewrite logic | expand |
--- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -492,9 +492,15 @@ void __init_or_module noinline apply_ret continue; } + DPRINTK("retpoline at: %pS (%px) len: %d to: %pS", + addr, addr, insn.length, + addr + insn.length + insn.immediate.value); + len = patch_retpoline(addr, &insn, bytes); if (len == insn.length) { optimize_nops(bytes, len); + DUMP_BYTES(((u8*)addr), len, "%px: orig: ", addr); + DUMP_BYTES(((u8*)bytes), len, "%px: repl: ", addr); text_poke_early(addr, bytes, len); } }
Make sure we can see the text changes when booting with 'debug-alternative'. Example output: [ ] SMP alternatives: retpoline at: __traceiter_initcall_level+0x1f/0x30 (ffffffff8100066f) len: 5 to: __x86_indirect_thunk_rax+0x0/0x20 [ ] SMP alternatives: ffffffff82603e58: [2:5) optimized NOPs: ff d0 0f 1f 00 [ ] SMP alternatives: ffffffff8100066f: orig: e8 cc 30 00 01 [ ] SMP alternatives: ffffffff8100066f: repl: ff d0 0f 1f 00 Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> --- arch/x86/kernel/alternative.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)