From 074376ac0e1d1fcd4fafebca86ee6158e7c20680 Mon Sep 17 00:00:00 2001 From: Jiri Kosina Date: Sat, 29 Jun 2019 23:22:33 +0200 Subject: [PATCH] ftrace/x86: Anotate text_mutex split between ftrace_arch_code_modify_post_process() and ftrace_arch_code_modify_prepare() ftrace_arch_code_modify_prepare() is acquiring text_mutex, while the corresponding release is happening in ftrace_arch_code_modify_post_process(). This has already been documented in the code, but let's also make the fact that this is intentional clear to the semantic analysis tools such as sparse. Link: http://lkml.kernel.org/r/nycvar.YFH.7.76.1906292321170.27227@cbobk.fhfr.pm Fixes: 39611265edc1a ("ftrace/x86: Add a comment to why we take text_mutex in ftrace_arch_code_modify_prepare()") Fixes: d5b844a2cf507 ("ftrace/x86: Remove possible deadlock between register_kprobe() and ftrace_run_update_code()") Signed-off-by: Jiri Kosina Signed-off-by: Steven Rostedt (VMware) --- arch/x86/kernel/ftrace.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index d7e93b2783fd..76228525acd0 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -35,6 +35,7 @@ #ifdef CONFIG_DYNAMIC_FTRACE int ftrace_arch_code_modify_prepare(void) + __acquires(&text_mutex) { /* * Need to grab text_mutex to prevent a race from module loading @@ -48,6 +49,7 @@ int ftrace_arch_code_modify_prepare(void) } int ftrace_arch_code_modify_post_process(void) + __releases(&text_mutex) { set_all_modules_text_ro(); set_kernel_text_ro(); -- GitLab