Re: [PATCH 12/13] x86/jitalloc: prepare to allocate exectuatble memory as ROX
From: Peter Zijlstra <peterz@infradead.org>
Date: 2023-06-01 10:31:56
Also in:
bpf, linux-arm-kernel, linux-mips, linux-modules, linux-riscv, linux-s390, linuxppc-dev, lkml, loongarch, netdev, sparclinux
On Thu, Jun 01, 2023 at 01:12:56PM +0300, Mike Rapoport wrote:
+static void __init_or_module do_text_poke(void *addr, const void *opcode, size_t len)
+{
+ if (system_state < SYSTEM_RUNNING) {
+ text_poke_early(addr, opcode, len);
+ } else {
+ mutex_lock(&text_mutex);
+ text_poke(addr, opcode, len);
+ mutex_unlock(&text_mutex);
+ }
+}So I don't much like do_text_poke(); why?
quoted hunk ↗ jump to hunk
diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index aa99536b824c..d50595f2c1a6 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c@@ -118,10 +118,13 @@ ftrace_modify_code_direct(unsigned long ip, const char *old_code, return ret; /* replace the text with the new text */ - if (ftrace_poke_late) + if (ftrace_poke_late) { text_poke_queue((void *)ip, new_code, MCOUNT_INSN_SIZE, NULL); - else - text_poke_early((void *)ip, new_code, MCOUNT_INSN_SIZE); + } else { + mutex_lock(&text_mutex); + text_poke((void *)ip, new_code, MCOUNT_INSN_SIZE); + mutex_unlock(&text_mutex); + } return 0; }
And in the above case it's actively wrong for loosing the _queue() thing.