On Sat, Jun 09, 2018 at 01:42:05PM +0200, Philip Müller wrote:

objtool ports introduced in v4.9.106 were not totally complete. Therefore they resulted in issues like:

module: overflow in relocation type 10 val XXXXXXXXXXX ‘usbcore’ likely not compiled with -mcmodel=kernel module: overflow in relocation type 10 val XXXXXXXXXXX ‘scsi_mod’ likely not compiled with -mcmodel=kernel

What is causing these messages? What arch and .config?

Missing part was the complete backport of commit e390f9a.

Ah, right, I missed those other parts of this commit, good catch.

Original notes by Josh Poimboeuf:

The '__unreachable' and '__func_stack_frame_non_standard' sections are only used at compile time. They're discarded for vmlinux but they should also be discarded for modules.

Since this is a recurring pattern, prefix the section names with ".discard.". It's a nice convention and vmlinux.lds.h already discards such sections.

Also remove the 'a' (allocatable) flag from the __unreachable section since it doesn't make sense for a discarded section.

Signed-off-by: Philip Müller philm@manjaro.org Fixes: d1091c7fa3d5 ("objtool: Improve detection of BUG() and other dead ends") Link: https://gitlab.manjaro.org/packages/core/linux49/issues/2

diff -Npur linux-4.9.106.orig/arch/x86/kernel/vmlinux.lds.S linux-4.9.106/arch/x86/kernel/vmlinux.lds.S --- linux-4.9.106.orig/arch/x86/kernel/vmlinux.lds.S 2018-06-09 12:43:04.238314000 +0200 +++ linux-4.9.106/arch/x86/kernel/vmlinux.lds.S 2018-06-09 12:44:39.034361441 +0200 @@ -352,8 +352,6 @@ SECTIONS DISCARDS /DISCARD/ : { *(.eh_frame)

• *(__func_stack_frame_non_standard)
  

• *(__unreachable)
  

  }

} diff -Npur linux-4.9.106.orig/include/linux/compiler-gcc.h linux-4.9.106/include/linux/compiler-gcc.h --- linux-4.9.106.orig/include/linux/compiler-gcc.h 2018-06-09 12:43:05.058337000 +0200 +++ linux-4.9.106/include/linux/compiler-gcc.h 2018-06-09 12:45:35.779367605 +0200 @@ -206,7 +206,7 @@ #ifdef CONFIG_STACK_VALIDATION #define annotate_unreachable() ({ \ asm("1:\t\n" \

•    ".pushsection __unreachable, \"a\"\t\n"			\
  

•    ".pushsection .discard.unreachable\t\n"			\
   ".long 1b\t\n"						\
   ".popsection\t\n");						\
  

})

What about the fix up to scripts/mod/modpost and module-common.lds? Are they not needed?

thanks,

greg k-h