Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit d2fae548 authored by Rusty Russell's avatar Rusty Russell Committed by Anton Blanchard
Browse files

powerpc: modules: change r2 save/restore offset for ELFv2 ABI. 



ELFv2 uses a different stack offset (24 vs 40) to save r2.

Signed-off-by: default avatarRusty Russell <rusty@rustcorp.com.au>
parent 5b12c5c6

arch/powerpc/kernel/module_64.c

+15 −8
Original line number Diff line number Diff line
@@ -41,6 +41,12 @@ 
#define DEBUGP(fmt , ...)

#endif



#if defined(_CALL_ELF) && _CALL_ELF == 2

#define R2_STACK_OFFSET 24

#else

#define R2_STACK_OFFSET 40

#endif



/* Like PPC32, we need little trampolines to do > 24-bit jumps (into

   the kernel itself).  But on PPC64, these need to be used for every

   jump, actually, to reset r2 (TOC+0x8000). */
@@ -64,7 +70,7 @@ static struct ppc64_stub_entry ppc64_stub = 
	0x3d820000,			/* addis   r12,r2, <high> */

	0x398c0000,			/* addi    r12,r12, <low> */

	/* Save current r2 value in magic place on the stack. */

	0xf8410028, /* std     r2,40(r1) */

	0xf8410000|R2_STACK_OFFSET,	/* std     r2,R2_STACK_OFFSET(r1) */

	0xe96c0020,			/* ld      r11,32(r12) */

	0xe84c0028,			/* ld      r2,40(r12) */

	0x7d6903a6,			/* mtctr   r11 */
@@ -338,7 +344,8 @@ static int restore_r2(u32 *instruction, struct module *me) 
		       me->name, *instruction);

		return 0;

	}

	*instruction = 0xe8410028;	/* ld r2,40(r1) */

	/* ld r2,R2_STACK_OFFSET(r1) */

	*instruction = 0xe8410000 | R2_STACK_OFFSET;

	return 1;

}