Commit cdcb07e4 authored May 14, 2020 by Vincent Whitchurch Committed by Russell King May 19, 2020

ARM: 8975/1: module: fix handling of unwind init sections



Unwind information for init sections is placed in .ARM.exidx.init.text
and .ARM.extab.init.text.  The module core doesn't know that these are
init sections so they are allocated along with the core sections, and if
the core and init sections get allocated in different memory regions
(which is possible with CONFIG_ARM_MODULE_PLTS=y) and they can't reach
each other, relocation fails:

  final section addresses:
  	...
  	0x7f800000 .init.text
	..
  	0xcbb54078 .ARM.exidx.init.text
	..

 section 16 reloc 0 sym '': relocation 42 out of range (0xcbb54078 ->
 0x7f800000)

Fix this by informing the module core that these sections are init
sections, and by removing the init unwind tables before the module core
frees the init sections.

Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

parent 0697e5e0

arch/arm/kernel/module.c

+19 −3

Original line number	Diff line number	Diff line
		@@ -55,6 +55,13 @@ void *module_alloc(unsigned long size)
		}
		#endif

		bool module_init_section(const char *name)
		{
		return strstarts(name, ".init") \|\|
		strstarts(name, ".ARM.extab.init") \|\|
		strstarts(name, ".ARM.exidx.init");
		}

		bool module_exit_section(const char *name)
		{
		return strstarts(name, ".exit") \|\|
		@@ -409,8 +416,17 @@ module_arch_cleanup(struct module *mod)
		#ifdef CONFIG_ARM_UNWIND
		int i;

		for (i = 0; i < ARM_SEC_MAX; i++)
		if (mod->arch.unwind[i])
		for (i = 0; i < ARM_SEC_MAX; i++) {
		unwind_table_del(mod->arch.unwind[i]);
		mod->arch.unwind[i] = NULL;
		}
		#endif
		}

		void __weak module_arch_freeing_init(struct module *mod)
		{
		#ifdef CONFIG_ARM_UNWIND
		unwind_table_del(mod->arch.unwind[ARM_SEC_INIT]);
		mod->arch.unwind[ARM_SEC_INIT] = NULL;
		#endif
		}

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