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| author | Jon Medhurst <tixy@linaro.org> | 2014-09-30 09:25:10 (GMT) |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2014-09-30 15:55:24 (GMT) |
| commit | ad684dce87fac52738649e62b4afa25081b52a28 (patch) | |
| tree | 42b37e2d471f9cdecc61018217cb4ad771f63149 | |
| parent | 9cc6d9e5daaa147a9a3e31557efcb331989e77be (diff) | |
| download | linux-ad684dce87fac52738649e62b4afa25081b52a28.tar.xz | |
ARM: 8179/1: kprobes-test: Fix compile error "bad immediate value for offset"
When compiling kprobes-test-arm.c the following error has been observed
/tmp/ccoT403o.s:21439: Error: bad immediate value for offset (4168)
This is caused by the compiler spilling it's literal pool too far away
from the site which is trying to reference it with a PC relative load.
This arises because the compiler is underestimating the size of the
inline assembler code present, which apparently it approximates as 4
bytes per line or instruction.
We fix this problem by moving the operations which generate more than
4 bytes out of the text section. Specifically, moving the .ascii
directives to the .rodata section.
Signed-off-by: Jon Medhurst <tixy@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
| -rw-r--r-- | arch/arm/kernel/kprobes-test.c | 16 | ||||
| -rw-r--r-- | arch/arm/kernel/kprobes-test.h | 5 |
2 files changed, 13 insertions, 8 deletions
diff --git a/arch/arm/kernel/kprobes-test.c b/arch/arm/kernel/kprobes-test.c index 08d7312..b206d77 100644 --- a/arch/arm/kernel/kprobes-test.c +++ b/arch/arm/kernel/kprobes-test.c @@ -110,10 +110,13 @@ * * @ TESTCASE_START * bl __kprobes_test_case_start - * @ start of inline data... + * .pushsection .rodata + * "10: * .ascii "mov r0, r7" @ text title for test case * .byte 0 - * .align 2, 0 + * .popsection + * @ start of inline data... + * .word 10b @ pointer to title in .rodata section * * @ TEST_ARG_REG * .byte ARG_TYPE_REG @@ -971,7 +974,7 @@ void __naked __kprobes_test_case_start(void) __asm__ __volatile__ ( "stmdb sp!, {r4-r11} \n\t" "sub sp, sp, #"__stringify(TEST_MEMORY_SIZE)"\n\t" - "bic r0, lr, #1 @ r0 = inline title string \n\t" + "bic r0, lr, #1 @ r0 = inline data \n\t" "mov r1, sp \n\t" "bl kprobes_test_case_start \n\t" "bx r0 \n\t" @@ -1349,15 +1352,14 @@ static unsigned long next_instruction(unsigned long pc) return pc + 4; } -static uintptr_t __used kprobes_test_case_start(const char *title, void *stack) +static uintptr_t __used kprobes_test_case_start(const char **title, void *stack) { struct test_arg *args; struct test_arg_end *end_arg; unsigned long test_code; - args = (struct test_arg *)PTR_ALIGN(title + strlen(title) + 1, 4); - - current_title = title; + current_title = *title++; + args = (struct test_arg *)title; current_args = args; current_stack = stack; diff --git a/arch/arm/kernel/kprobes-test.h b/arch/arm/kernel/kprobes-test.h index eecc90a..4430990 100644 --- a/arch/arm/kernel/kprobes-test.h +++ b/arch/arm/kernel/kprobes-test.h @@ -111,11 +111,14 @@ struct test_arg_end { #define TESTCASE_START(title) \ __asm__ __volatile__ ( \ "bl __kprobes_test_case_start \n\t" \ + ".pushsection .rodata \n\t" \ + "10: \n\t" \ /* don't use .asciz here as 'title' may be */ \ /* multiple strings to be concatenated. */ \ ".ascii "#title" \n\t" \ ".byte 0 \n\t" \ - ".align 2, 0 \n\t" + ".popsection \n\t" \ + ".word 10b \n\t" #define TEST_ARG_REG(reg, val) \ ".byte "__stringify(ARG_TYPE_REG)" \n\t" \ |