From: Andreas Bießmann Date: Thu, 24 Oct 2013 10:31:04 +0000 (+0200) Subject: avr32: fix out-of-range jump in large kernels X-Git-Tag: v3.2.54~110 X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1c7fd3120a35b27aad3ed7b2a6e72714938c4e66;p=pandora-kernel.git avr32: fix out-of-range jump in large kernels commit d617b338bbfdd77e9cbd8e7dc949cee3dd73d575 upstream. This patch fixes following error (for big kernels): ---8<--- arch/avr32/boot/u-boot/head.o: In function `no_tag_table': (.init.text+0x44): relocation truncated to fit: R_AVR32_22H_PCREL against symbol `panic' defined in .text.unlikely section in kernel/built-in.o arch/avr32/kernel/built-in.o: In function `bad_return': (.ex.text+0x236): relocation truncated to fit: R_AVR32_22H_PCREL against symbol `panic' defined in .text.unlikely section in kernel/built-in.o --->8--- It comes up when the kernel increases and 'panic()' is too far away to fit in the +/- 2MiB range. Which in turn issues from the 21-bit displacement in 'br{cond4}' mnemonic which is one of the two ways to do jumps (rjmp has just 10-bit displacement and therefore a way smaller range). This fact was stated before in 8d29b7b9f81d6b83d869ff054e6c189d6da73f1f. One solution to solve this is to add a local storage for the symbol address and just load the $pc with that value. Signed-off-by: Andreas Bießmann Acked-by: Hans-Christian Egtvedt Cc: Haavard Skinnemoen Signed-off-by: Ben Hutchings --- diff --git a/arch/avr32/boot/u-boot/head.S b/arch/avr32/boot/u-boot/head.S index d36d865308df..2ffc298f061b 100644 --- a/arch/avr32/boot/u-boot/head.S +++ b/arch/avr32/boot/u-boot/head.S @@ -73,8 +73,11 @@ init_sr: .long 0x007f0000 /* Supervisor mode, everything masked */ stack_addr: .long init_thread_union +panic_addr: + .long panic no_tag_table: sub r12, pc, (. - 2f) - bral panic + /* branch to panic() which can be far away with that construct */ + lddpc pc, panic_addr 2: .asciz "Boot loader didn't provide correct magic number\n" diff --git a/arch/avr32/kernel/entry-avr32b.S b/arch/avr32/kernel/entry-avr32b.S index 169268c40ae2..a91e8980a590 100644 --- a/arch/avr32/kernel/entry-avr32b.S +++ b/arch/avr32/kernel/entry-avr32b.S @@ -399,9 +399,10 @@ handle_critical: /* We should never get here... */ bad_return: sub r12, pc, (. - 1f) - bral panic + lddpc pc, 2f .align 2 1: .asciz "Return from critical exception!" +2: .long panic .align 1 do_bus_error_write: