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..f16fa7d 100644 --- a/arch/parisc/kernel/vmlinux.lds.S +++ b/arch/parisc/kernel/vmlinux.lds.S @@ -67,6 +78,10 @@ SECTIONS *(.fixup) *(.lock.text) /* out-of-line lock text */ *(.gnu.warning) +#if defined(CONFIG_64BIT) && !defined(CONFIG_MLONGCALLS) + INIT_TEXT + EXIT_TEXT +#endif } /* End of text section */ _etext = .; -- To unsubscribe from this list: send the line "unsubscribe linux-parisc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
