Here is an updated (complete) patch.
* Helge Deller <deller@xxxxxx>:
> When building the 64bit SMP kernel for debian it may happen that it becomes too
> big so that functions in the .init.text or .exit.text may not be able to reach
> important kernel functions in the .text section. Main reason why this happens
> with a 64bit kernel build is that we include the linkage tables (.opd, .plt,
> .dlt) in that data section. Those linkage tables tend to become huge, and
> since they are located between the .text and the .init sections the distance
> gets too far.
>
> If the linker fails to link vmlinux, it will either crash without any error
> message, or it will - with newer linker versions - report the following error:
>
> hppa64-linux-gnu-ld: drivers/built-in.o(.exit.text+0xc4): cannot reach _raw_read_lock
> drivers/built-in.o: In function `pdc_stable_exit':
> drivers/parisc/pdc_stable.o:(.exit.text+0xc4): relocation truncated to fit: R_PARISC_PCREL22F against symbol `_raw_read_lock' defined in .spinlock.text section in kernel/built-in.o
>
> We have three options to solve this issue:
> a) Turn on CONFIG_MLONGCALLS, which will instruct the compiler to use the
> -mlongcall option. But this option will hurt performance.
> b) Tell the linker (via vmlinux.lds.S) to move the .init.text and .exit.text
> sections into the normal .text section. Downside here is, that those sections
> will not be discarded at runtime.
> c) Move the linkage tables somewhere else. Even if this would be possible I did
> not find a nice solution without any other bad side effects.
>
> Since we are compiling a 64bit kernel which usually runs on machines with lots
> of memory, I preferred option b) since performance is usually more imortant than
> some lost memory area.
>
> Signed-off-by: Helge Deller <deller@xxxxxx>
diff --git a/arch/parisc/kernel/vmlinux.lds.S b/arch/parisc/kernel/vmlinux.lds.S
index 4bb095a..4d7a1f0 100644
--- a/arch/parisc/kernel/vmlinux.lds.S
+++ b/arch/parisc/kernel/vmlinux.lds.S
@@ -23,13 +23,23 @@
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
+
+/*
+ * Put page table entries (swapper_pg_dir) as the first thing in .bss. This
+ * will ensure that it has .bss alignment (PAGE_SIZE).
+ */
+#define BSS_FIRST_SECTIONS *(.data..vm0.pmd) \
+ *(.data..vm0.pgd) \
+ *(.data..vm0.pte)
+
#include <asm-generic/vmlinux.lds.h>
+
/* needed for the processor specific cache alignment size */
#include <asm/cache.h>
#include <asm/page.h>
#include <asm/asm-offsets.h>
#include <asm/thread_info.h>
-
+
/* ld script to make hppa Linux kernel */
#ifndef CONFIG_64BIT
OUTPUT_FORMAT("elf32-hppa-linux")
@@ -53,6 +63,7 @@ SECTIONS
.head ALIGN(16) : {
HEAD_TEXT
} = 0
+
.text ALIGN(16) : {
TEXT_TEXT
SCHED_TEXT
@@ -64,17 +75,23 @@ SECTIONS
*(.text.do_sigaltstack)
*(.text.do_fork)
*(.text.*)
+#if defined(CONFIG_64BIT) && !defined(CONFIG_MLONGCALLS)
+ EXIT_TEXT
+#endif
*(.fixup)
*(.lock.text) /* out-of-line lock text */
*(.gnu.warning)
}
+#if defined(CONFIG_64BIT) && !defined(CONFIG_MLONGCALLS)
+ INIT_TEXT_SECTION(16)
+#endif
/* End of text section */
_etext = .;
/* Start of data section */
_sdata = .;
- RODATA
+ RO_DATA_SECTION(PAGE_SIZE)
/* writeable */
/* Make sure this is page aligned so
@@ -107,45 +124,36 @@ SECTIONS
_edata = .;
/* BSS */
- __bss_start = .;
- /* page table entries need to be PAGE_SIZE aligned */
- . = ALIGN(PAGE_SIZE);
- .data..vmpages : {
- *(.data..vm0.pmd)
- *(.data..vm0.pgd)
- *(.data..vm0.pte)
- }
- .bss : {
- *(.bss)
- *(COMMON)
- }
- __bss_stop = .;
+ BSS_SECTION(16, PAGE_SIZE, 16)
+
#ifdef CONFIG_64BIT
+ /* Linkage tables are huge. */
. = ALIGN(16);
/* Linkage tables */
.opd : {
*(.opd)
- } PROVIDE (__gp = .);
+ } PROVIDE (__gp = .);
.plt : {
*(.plt)
- }
+ }
.dlt : {
*(.dlt)
}
#endif
- /* reserve space for interrupt stack by aligning __init* to 16k */
- . = ALIGN(16384);
- __init_begin = .;
- INIT_TEXT_SECTION(16384)
. = ALIGN(PAGE_SIZE);
- INIT_DATA_SECTION(16)
+ __init_begin = .;
+
+#if !defined(CONFIG_64BIT) || defined(CONFIG_MLONGCALLS)
+ INIT_TEXT_SECTION(16)
/* we have to discard exit text and such at runtime, not link time */
.exit.text :
{
EXIT_TEXT
}
+#endif
+ INIT_DATA_SECTION(16)
.exit.data :
{
EXIT_DATA
--
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