Re: [PATCH] module: set __jump_table alignment to 8

[Jessica Yu]

+++ David Daney [02/03/17 11:24 -0800]:
> On 03/02/2017 10:26 AM, Jessica Yu wrote:
> > +++ Steven Rostedt [02/03/17 13:11 -0500]:
> > > Can I get an Ack from a module maintainer?
> >
> > Acked-by: Jessica Yu <jeyu@xxxxxxxxxx>
> >
> > Thanks!
> >
> > Jessica
>
> Thanks Jessica,
>
> Can you also add scripts/module-common.lds to MAINTAINERS so that 
> get_maintainers.pl will indicate that Jessica Yu and Rusty Russell be 
> CCed on things like this in the future?

Sure thing. Thanks for the heads up!

Jessica

> > > On Wed,  1 Mar 2017 14:04:53 -0800
> > > David Daney <david.daney@xxxxxxxxxx> wrote:
> > >
> > > > For powerpc the __jump_table section in modules is not aligned, this
> > > > causes a WARN_ON() splat when loading a module containing a
> > > > __jump_table.
> > > >
> > > > Strict alignment became necessary with commit 3821fd35b58d
> > > > ("jump_label: Reduce the size of struct static_key"), currently in
> > > > linux-next, which uses the two least significant bits of pointers to
> > > > __jump_table elements.
> > > >
> > > > Fix by forcing __jump_table to 8, which is the same alignment used for
> > > > this section in the kernel proper.
> > > >
> > > > Signed-off-by: David Daney <david.daney@xxxxxxxxxx>
> > > > Tested-by: Sachin Sant <sachinp@xxxxxxxxxxxxxxxxxx>
> > > > ---
> > > > scripts/module-common.lds | 2 ++
> > > > 1 file changed, 2 insertions(+)
> > > >
> > > > diff --git a/scripts/module-common.lds b/scripts/module-common.lds
> > > > index 73a2c7d..53234e8 100644
> > > > --- a/scripts/module-common.lds
> > > > +++ b/scripts/module-common.lds
> > > > @@ -19,4 +19,6 @@ SECTIONS {
> > > >
> > > >     . = ALIGN(8);
> > > >     .init_array        0 : { *(SORT(.init_array.*)) *(.init_array) }
> > > > +
> > > > +    __jump_table        0 : ALIGN(8) { KEEP(*(__jump_table)) }
> > > > }