On Wed, Feb 22, 2023 at 11:56 AM <guoren@xxxxxxxxxx> wrote: > > From: Lai Jiangshan <laijs@xxxxxxxxxxxxxxxxx> > > Using __noinstr_section() doesn't automatically disable all > instrumentations on the section. Inhibition for some > instrumentations requires extra code. I.E. KPROBES explicitly > avoids instrumenting on .noinstr.text. > > Suggested-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> > Suggested-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx> > Reviewed-by: Miguel Ojeda <ojeda@xxxxxxxxxx> > Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx> > Reviewed-by: Björn Töpel <bjorn@xxxxxxxxxxxx> > Tested-by: Jisheng Zhang <jszhang@xxxxxxxxxx> > Tested-by: Guo Ren <guoren@xxxxxxxxxx> > Signed-off-by: Lai Jiangshan <laijs@xxxxxxxxxxxxxxxxx> > Signed-off-by: Guo Ren <guoren@xxxxxxxxxx> Hello The change has been made upstream as a part of the commit 2b5a0e425e6e(objtool/idle: Validate __cpuidle code as noinstr). https://lore.kernel.org/r/20230112195540.373461409@xxxxxxxxxxxxx Thanks Lai > --- > include/linux/compiler_types.h | 15 +++++++++++---- > 1 file changed, 11 insertions(+), 4 deletions(-) > > diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h > index 7c1afe0f4129..0a2ca5755be7 100644 > --- a/include/linux/compiler_types.h > +++ b/include/linux/compiler_types.h > @@ -231,12 +231,19 @@ struct ftrace_likely_data { > #define __no_sanitize_or_inline __always_inline > #endif > > -/* Section for code which can't be instrumented at all */ > -#define noinstr \ > - noinline notrace __attribute((__section__(".noinstr.text"))) \ > - __no_kcsan __no_sanitize_address __no_profile __no_sanitize_coverage \ > +/* > + * Using __noinstr_section() doesn't automatically disable all instrumentations > + * on the section. Inhibition for some instrumentations requires extra code. > + * I.E. KPROBES explicitly avoids instrumenting on .noinstr.text. > + */ > +#define __noinstr_section(section) \ > + noinline notrace __section(section) __no_profile \ > + __no_kcsan __no_sanitize_address __no_sanitize_coverage \ > __no_sanitize_memory > > +/* Section for code which can't be instrumented at all */ > +#define noinstr __noinstr_section(".noinstr.text") > + > #endif /* __KERNEL__ */ > > #endif /* __ASSEMBLY__ */ > -- > 2.36.1 >
