Commit 8dcf86ca authored Sep 13, 2018 by Peter Oberparleiter Committed by Stephen Rothwell Oct 12, 2018

vmlinux.lds.h: Fix incomplete .text.exit discards



Enabling CONFIG_GCOV_PROFILE_ALL=y causes linker errors on ARM:

  `.text.exit' referenced in section `.ARM.exidx.text.exit':
  defined in discarded section `.text.exit'

  `.text.exit' referenced in section `.fini_array.00100':
  defined in discarded section `.text.exit'

And related errors on NDS32:

  `.text.exit' referenced in section `.dtors.65435':
  defined in discarded section `.text.exit'

The gcov compiler flags cause certain compiler versions to generate
additional destructor-related sections that are not yet handled by the
linker script, resulting in references between discarded and
non-discarded sections.

Since destructors are not used in the Linux kernel, fix this by
discarding these additional sections.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Reported-by: Greentime Hu <green.hu@gmail.com>
Tested-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>

parent 0778a9f2

arch/arm/kernel/vmlinux.lds.h

+2 −0

Original line number	Original line	Diff line number	Diff line
	@@ -49,6 +49,8 @@
	#define ARM_DISCARD \		#define ARM_DISCARD \
	*(.ARM.exidx.exit.text) \		*(.ARM.exidx.exit.text) \
	*(.ARM.extab.exit.text) \		*(.ARM.extab.exit.text) \
			*(.ARM.exidx.text.exit) \
			*(.ARM.extab.text.exit) \
	ARM_CPU_DISCARD(*(.ARM.exidx.cpuexit.text)) \		ARM_CPU_DISCARD(*(.ARM.exidx.cpuexit.text)) \
	ARM_CPU_DISCARD(*(.ARM.extab.cpuexit.text)) \		ARM_CPU_DISCARD(*(.ARM.extab.cpuexit.text)) \
	ARM_EXIT_DISCARD(EXIT_TEXT) \		ARM_EXIT_DISCARD(EXIT_TEXT) \

include/asm-generic/vmlinux.lds.h

+2 −2

Original line number	Original line	Diff line number	Diff line
	@@ -613,8 +613,8 @@

	#define EXIT_DATA \		#define EXIT_DATA \
	(.exit.data .exit.data.) \		(.exit.data .exit.data.) \
	*(.fini_array) \		(.fini_array .fini_array.) \
	*(.dtors) \		(.dtors .dtors.) \
	MEM_DISCARD(exit.data*) \		MEM_DISCARD(exit.data*) \
	MEM_DISCARD(exit.rodata*)		MEM_DISCARD(exit.rodata*)