Re: [PATCH v2] srcu: avoid escaped section names

From: Nick Desaulniers
Date: Mon Oct 05 2020 - 14:29:44 EST


On Fri, Oct 2, 2020 at 1:51 PM Paul E. McKenney <paulmck@xxxxxxxxxx> wrote:
>
> On Wed, Sep 30, 2020 at 01:55:48PM -0700, Nick Desaulniers wrote:
> > On Wed, Sep 30, 2020 at 1:40 PM Paul E. McKenney <paulmck@xxxxxxxxxx> wrote:
> > >
> > > On Tue, Sep 29, 2020 at 12:25:49PM -0700, Nick Desaulniers wrote:
> > > > The stringification operator, `#`, in the preprocessor escapes strings.
> > > > For example, `# "foo"` becomes `"\"foo\""`. GCC and Clang differ in how
> > > > they treat section names that contain \".
> > > >
> > > > The portable solution is to not use a string literal with the
> > > > preprocessor stringification operator.
> > > >
> > > > Link: https://bugs.llvm.org/show_bug.cgi?id=42950
> > > > Fixes: commit fe15b50cdeee ("srcu: Allocate per-CPU data for DEFINE_SRCU() in modules")
> > > > Signed-off-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
> > >
> > > I am guessing that this needs to go up with other patches. If so:
> > >
> > > Acked-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
> > >
> > > If not, let me know and I will queue it.
> >
> > I could have bundled them up as a series. I think you can pick it up,
> > and I'll owe you a beer?
>
> It is queued, thank you!
>
> When does it need to hit mainline? (Your default is the v5.11 merge
> window, that is, the one following the upcoming merge window.)

No rush, this patch wasn't blocking any known issue, just a cleanup
while I was in the neighborhood. 100 years ago, I was an Eagle scout.
Pretty sure there was a motto about "leaving things better than you
found them." Thanks for help resolving the merge conflict reported in
-next related to it.

>
>
> Thanx, Paul
>
> > > > ---
> > > > Changes V1->V2:
> > > > * drop unrelated Kconfig changes accidentally committed in v1.
> > > >
> > > > include/linux/srcutree.h | 2 +-
> > > > 1 file changed, 1 insertion(+), 1 deletion(-)
> > > >
> > > > diff --git a/include/linux/srcutree.h b/include/linux/srcutree.h
> > > > index 9cfcc8a756ae..9de652f4e1bd 100644
> > > > --- a/include/linux/srcutree.h
> > > > +++ b/include/linux/srcutree.h
> > > > @@ -124,7 +124,7 @@ struct srcu_struct {
> > > > # define __DEFINE_SRCU(name, is_static) \
> > > > is_static struct srcu_struct name; \
> > > > struct srcu_struct * const __srcu_struct_##name \
> > > > - __section("___srcu_struct_ptrs") = &name
> > > > + __section(___srcu_struct_ptrs) = &name
> > > > #else
> > > > # define __DEFINE_SRCU(name, is_static) \
> > > > static DEFINE_PER_CPU(struct srcu_data, name##_srcu_data); \
> > > > --
> > > > 2.28.0.709.gb0816b6eb0-goog
> > > >
> >
> >
> >
> > --
> > Thanks,
> > ~Nick Desaulniers



--
Thanks,
~Nick Desaulniers