[RFC PATCH 2/4] x86/alternatives: Print containing function

From: Borislav Petkov
Date: Tue Dec 11 2018 - 17:23:50 EST


From: Borislav Petkov <bp@xxxxxxx>

... in the "debug-alternative" output so that one can find her way
easier when staring at the vmlinux disassembly.

For example:

apply_alternatives: feat: 3*32+18, old: (read_tsc+0x0/0x10 (ffffffff8101d1c0) len: 5), repl: (ffffffff824e6d33, len: 5)
^^^^^^^^^^^^^^^^^
ffffffff8101d1c0: old_insn: 0f 31 90 90 90
ffffffff824e6d33: rpl_insn: 0f ae e8 0f 31
ffffffff8101d1c0: final_insn: 0f ae e8 0f 31

No functional changes.

Signed-off-by: Borislav Petkov <bp@xxxxxxx>
---
arch/x86/kernel/alternative.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index ebeac487a20c..d458c7973c56 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -393,10 +393,10 @@ void __init_or_module noinline apply_alternatives(struct alt_instr *start,
continue;
}

- DPRINTK("feat: %d*32+%d, old: (%px len: %d), repl: (%px, len: %d), pad: %d",
+ DPRINTK("feat: %d*32+%d, old: (%pS (%px) len: %d), repl: (%px, len: %d), pad: %d",
a->cpuid >> 5,
a->cpuid & 0x1f,
- instr, a->instrlen,
+ instr, instr, a->instrlen,
replacement, a->replacementlen, a->padlen);

DUMP_BYTES(instr, a->instrlen, "%px: old_insn: ", instr);
--
2.19.1