When kprobes is used, most of the entry-armv.S file is put into the
.kprobes.text
section rather than .text, but the kuser_cmpxchg64_fixup and
kuser_cmpxchg32_fixup
code is not, which can lead to a link error when extremely large kernels get
built (typically for randconfig):
arch/arm/kernel/built-in.o: In function `__dabt_usr':
:(.kprobes.text+0x47c): relocation truncated to fit: R_ARM_JUMP24 against
`.text'
arch/arm/kernel/built-in.o: In function `__irq_usr':
:(.kprobes.text+0x4e4): relocation truncated to fit: R_ARM_JUMP24 against
`.text'
arch/arm/kernel/built-in.o: In function `__fiq_usr':
:(.kprobes.text+0x740): relocation truncated to fit: R_ARM_JUMP24 against
`.text'
This moves the two remaining functions into the same section as the rest,
to avoid the link error.
The current behavior has existed for many years and has not caused problems in
practice except for extreme randconfig builds, so the patch should not need to
get backported.
Signed-off-by: Arnd Bergmann <a...@arndb.de>
Fixes: b49c0f24cf67 ("[ARM] 4659/1: remove possibilities for spurious false
negative with __kuser_cmpxchg")
Fixes: 785d3cd286f0 ("ARM kprobes: prevent some functions involved with kprobes
from being probed")
---
arch/arm/kernel/entry-armv.S | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S
index e2550500486d..030e43a0dce8 100644
--- a/arch/arm/kernel/entry-armv.S
+++ b/arch/arm/kernel/entry-armv.S
@@ -895,7 +895,11 @@ __kuser_cmpxchg64: @ 0xffff0f60
rsbs r0, r3, #0 @ set return val and C flag
ldmfd sp!, {r4, r5, r6, pc}
+#ifdef CONFIG_KPROBES
+ .section .kprobes.text,"ax",%progbits
+#else
.text
+#endif
kuser_cmpxchg64_fixup:
@ Called from kuser_cmpxchg_fixup.
@ r4 = address of interrupted insn (must be preserved).
@@ -953,7 +957,11 @@ __kuser_cmpxchg: @ 0xffff0fc0
rsbs r0, r3, #0 @ set return val and C flag
usr_ret lr
+#ifdef CONFIG_KPROBES
+ .section .kprobes.text,"ax",%progbits
+#else
.text
+#endif
kuser_cmpxchg32_fixup:
@ Called from kuser_cmpxchg_check macro.
@ r4 = address of interrupted insn (must be preserved).
--
2.7.0
