From 04e448d9a386640a79a4aa71251aa1cdd314f662 Mon Sep 17 00:00:00 2001 From: Tim Abbott Date: Sun, 12 Jul 2009 18:23:33 -0400 Subject: vmlinux.lds.h: restructure BSS linker script macros The BSS section macros in vmlinux.lds.h currently place the .sbss input section outside the bounds of [__bss_start, __bss_end]. On all architectures except for microblaze that handle both .sbss and __bss_start/__bss_end, this is wrong: the .sbss input section is within the range [__bss_start, __bss_end]. Relatedly, the example code at the top of the file actually has __bss_start/__bss_end defined twice; I believe the right fix here is to define them in the BSS_SECTION macro but not in the BSS macro. Another problem with the current macros is that several architectures have an ALIGN(4) or some other small number just before __bss_stop in their linker scripts. The BSS_SECTION macro currently hardcodes this to 4; while it should really be an argument. It also ignores its sbss_align argument; fix that. mn10300 is the only user at present of any of the macros touched by this patch. It looks like mn10300 actually was incorrectly converted to use the new BSS() macro (the alignment of 4 prior to conversion was a __bss_stop alignment, but the argument to the BSS macro is a start alignment). So fix this as well. I'd like acks from Sam and David on this one. Also CCing Paul, since he has a patch from me which will need to be updated to use BSS_SECTION(0, PAGE_SIZE, 4) once this gets merged. Signed-off-by: Tim Abbott Cc: Paul Mundt Cc: David Howells Signed-off-by: Sam Ravnborg --- include/asm-generic/vmlinux.lds.h | 19 +++++++++---------- 1 file changed, 9 insertions(+), 10 deletions(-) (limited to 'include/asm-generic') diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index a553f1041cf..6ad76bf5fb4 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -30,9 +30,7 @@ * EXCEPTION_TABLE(...) * NOTES * - * __bss_start = .; - * BSS_SECTION(0, 0) - * __bss_stop = .; + * BSS_SECTION(0, 0, 0) * _end = .; * * /DISCARD/ : { @@ -489,7 +487,8 @@ * bss (Block Started by Symbol) - uninitialized data * zeroed during startup */ -#define SBSS \ +#define SBSS(sbss_align) \ + . = ALIGN(sbss_align); \ .sbss : AT(ADDR(.sbss) - LOAD_OFFSET) { \ *(.sbss) \ *(.scommon) \ @@ -498,12 +497,10 @@ #define BSS(bss_align) \ . = ALIGN(bss_align); \ .bss : AT(ADDR(.bss) - LOAD_OFFSET) { \ - VMLINUX_SYMBOL(__bss_start) = .; \ *(.bss.page_aligned) \ *(.dynbss) \ *(.bss) \ *(COMMON) \ - VMLINUX_SYMBOL(__bss_stop) = .; \ } /* @@ -735,8 +732,10 @@ INIT_RAM_FS \ } -#define BSS_SECTION(sbss_align, bss_align) \ - SBSS \ +#define BSS_SECTION(sbss_align, bss_align, stop_align) \ + . = ALIGN(sbss_align); \ + VMLINUX_SYMBOL(__bss_start) = .; \ + SBSS(sbss_align) \ BSS(bss_align) \ - . = ALIGN(4); - + . = ALIGN(stop_align); \ + VMLINUX_SYMBOL(__bss_stop) = .; -- cgit v1.2.3-70-g09d2