Nouveau - Jul 2017 - [regression drm/noveau] suspend to ram -> BOOM: exception RIP: drm_calc_vbltimestamp_from_scanoutpos+335

On Fri, 2017-07-14 at 18:10 +0200, Peter Zijlstra wrote:
> On Fri, Jul 14, 2017 at 05:58:18PM +0200, Mike Galbraith wrote:
> > On Fri, 2017-07-14 at 17:50 +0200, Peter Zijlstra wrote:
> 
> > > Urgh, is for some mysterious reason the __bug_table section of
modules
> > > ending up in RO memory?
> > > 
> > > I forever get lost in that link magic :/
> > 
> > +1
> > 
> > drm.ko
> >  20
__bug_table   00000630  0000000000000000  0000000000000000  0004bff3  2**0
> >                   CONTENTS, ALLOC, LOAD, RELOC, READONLY, DATA
> > vmlinux
> >  15 __bug_table   0000ba84  ffffffff81af26c0  0000000001af26c0 
00cf26c0  2**0
> >                   CONTENTS, ALLOC, LOAD, READONLY, DATA
> > 
> > Danged if I know... um um RELOC business mucks things up?
> 
> Argh, it shouldn't be READONLY for vmlinux either, but apparently that
> is working for mysterious reasons.
> 
> Some architectures were in fact complaining that I broke that, and hence
> patch:
> 
> b5effd3815cc ("debug: Fix __bug_table[] in arch linker scripts")
> 
> I think we need professional help with this linking stuff, but who to
> ask?
Andy Lutomirski?

On Fri, 2017-07-14 at 14:42 -0500, Josh Poimboeuf wrote:
> 
> Does this fix it?
Yup, both READONLY __bug_table and "extra stern" warning are gone.
> diff --git a/arch/x86/include/asm/bug.h b/arch/x86/include/asm/bug.h
> index 39e702d..aa6b202 100644
> --- a/arch/x86/include/asm/bug.h
> +++ b/arch/x86/include/asm/bug.h
> @@ -35,7 +35,7 @@
>  #define _BUG_FLAGS(ins, flags)						\
>  do {									\
>  	asm volatile("1:\t" ins "\n"					\
> -		     ".pushsection __bug_table,\"a\"\n"			\
> +		     ".pushsection __bug_table,\"aw\"\n"		\
>  		     "2:\t" __BUG_REL(1b) "\t#
bug_entry::bug_addr\n"	\
>  		     "\t"  __BUG_REL(%c0) "\t# bug_entry::file\n"	\
>  		     "\t.word %c1"        "\t# bug_entry::line\n"	\
> @@ -52,7 +52,7 @@ do {									\
>  #define _BUG_FLAGS(ins, flags)						\
>  do {									\
>  	asm volatile("1:\t" ins "\n"					\
> -		     ".pushsection __bug_table,\"a\"\n"			\
> +		     ".pushsection __bug_table,\"aw\"\n"		\
>  		     "2:\t" __BUG_REL(1b) "\t#
bug_entry::bug_addr\n"	\
>  		     "\t.word %c0"        "\t# bug_entry::flags\n"	\
>  		     "\t.org 2b+%c1\n"					\