Subject: [PATCH 1/8] ARM: ftrace: ensure that ADR take Thumb bit into account

From: Ard Biesheuvel <[email-masked]>
Date: Tue, 25 Jan 2022 16:36:49 +0100

Using ADR to take the address of 'ftrace_stub' via a local label
produces an address that has the Thumb bit cleared, which means the
subsequent comparison is guaranteed to fail. Instead, use the badr
macro, which forces the Thumb bit to be set.

Fixes: a3ba87a61499 ("ARM: 6316/1: ftrace: add Thumb-2 support")
Signed-off-by: Ard Biesheuvel <[email-masked]>
---
 arch/arm/kernel/entry-ftrace.S | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/kernel/entry-ftrace.S b/arch/arm/kernel/entry-ftrace.S
index a74289ebc803..f4886fb6e9ba 100644
--- a/arch/arm/kernel/entry-ftrace.S
+++ b/arch/arm/kernel/entry-ftrace.S
@@ -40,7 +40,7 @@
 	mcount_enter
 	ldr	r0, =ftrace_trace_function
 	ldr	r2, [r0]
-	adr	r0, .Lftrace_stub
+	badr	r0, .Lftrace_stub
 	cmp	r0, r2
 	bne	1f
 
-- 
2.30.2

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