From: Jiri Kosina Date: Sat, 29 Jun 2019 21:22:33 +0000 (+0200) Subject: ftrace/x86: Anotate text_mutex split between ftrace_arch_code_modify_post_process... X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=64219b370e89acbdd7385ddc5e2c759c7b5809b7;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git ftrace/x86: Anotate text_mutex split between ftrace_arch_code_modify_post_process() and ftrace_arch_code_modify_prepare() commit 074376ac0e1d1fcd4fafebca86ee6158e7c20680 upstream. 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) Cc: Guenter Roeck Signed-off-by: Greg Kroah-Hartman --- diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index ccc2b9d2956a..387340b1f6db 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -36,6 +36,7 @@ #ifdef CONFIG_DYNAMIC_FTRACE int ftrace_arch_code_modify_prepare(void) + __acquires(&text_mutex) { mutex_lock(&text_mutex); set_kernel_text_rw(); @@ -44,6 +45,7 @@ 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();