Commit faaae2a5 authored Nov 29, 2016 by Linus Torvalds

Re-enable CONFIG_MODVERSIONS in a slightly weaker form



This enables CONFIG_MODVERSIONS again, but allows for missing symbol CRC
information in order to work around the issue that newer binutils
versions seem to occasionally drop the CRC on the floor.  binutils 2.26
seems to work fine, while binutils 2.27 seems to break MODVERSIONS of
symbols that have been defined in assembler files.

[ We've had random missing CRC's before - it may be an old problem that
  just is now reliably triggered with the weak asm symbols and a new
  version of binutils ]

Some day I really do want to remove MODVERSIONS entirely.  Sadly, today
does not appear to be that day: Debian people apparently do want the
option to enable MODVERSIONS to make it easier to have external modules
across kernel versions, and this seems to be a fairly minimal fix for
the annoying problem.

Cc: Ben Hutchings <ben@decadent.org.uk>
Acked-by: Michal Marek <mmarek@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 22d3d4fb

init/Kconfig

+0 −1

Original line number	Diff line number	Diff line
		@@ -1945,7 +1945,6 @@ config MODULE_FORCE_UNLOAD

		config MODVERSIONS
		bool "Module versioning support"
		depends on BROKEN
		help
		Usually, you have to use modules compiled with your kernel.
		Saying Y here makes it sometimes possible to use modules

kernel/module.c

+3 −2

Original line number	Diff line number	Diff line
		@@ -1301,8 +1301,9 @@ static int check_version(Elf_Shdr *sechdrs,
		goto bad_version;
		}

		pr_warn("%s: no symbol version for %s\n", mod->name, symname);
		return 0;
		/* Broken toolchain. Warn once, then let it go.. */
		pr_warn_once("%s: no symbol version for %s\n", mod->name, symname);
		return 1;

		bad_version:
		pr_warn("%s: disagrees about version of symbol %s\n",

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