Commit 80375980 authored Feb 08, 2014 by Joe Mario Committed by H. Peter Anvin Feb 13, 2014

lto: Handle LTO common symbols in module loader



Here is the workaround I made for having the kernel not reject modules
built with -flto.  The clean solution would be to get the compiler to not
emit the symbol.  Or if it has to emit the symbol, then emit it as
initialized data but put it into a comdat/linkonce section.

Minor tweaks by AK over Joe's patch.

Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1391846481-31491-5-git-send-email-ak@linux.intel.com


Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

parent ef1b893c

kernel/module.c

+4 −0

Original line number	Diff line number	Diff line
		@@ -1948,6 +1948,10 @@ static int simplify_symbols(struct module mod, const struct load_info info)

		switch (sym[i].st_shndx) {
		case SHN_COMMON:
		/* Ignore common symbols */
		if (!strncmp(name, "__gnu_lto", 9))
		break;

		/* We compiled with -fno-common. These are not
		supposed to happen. */
		pr_debug("Common symbol: %s\n", name);

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