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Commit b70cd406 authored by Vladimir Murzin's avatar Vladimir Murzin Committed by Russell King
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ARM: 8671/1: V7M: Preserve registers across switch from Thread to Handler mode 



According to ARMv7 ARM, when exception is taken content of r0-r3, r12
is unknown (see ExceptionTaken() pseudocode). Even though existent
implementations keep these register unchanged, preserve them to be in
line with architecture.

Reported-by: default avatarDobromir Stefanov <dobromir.stefanov@arm.com>
Signed-off-by: default avatarVladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: default avatarRussell King <rmk+kernel@armlinux.org.uk>
parent 6f05d076

arch/arm/mm/proc-v7m.S

+2 −0
Original line number Diff line number Diff line
@@ -135,9 +135,11 @@ __v7m_setup_cont: 
	dsb

	mov	r6, lr			@ save LR

	ldr	sp, =init_thread_union + THREAD_START_SP

	stmia	sp, {r0-r3, r12}

	cpsie	i

	svc	#0

1:	cpsid	i

	ldmia	sp, {r0-r3, r12}

	str	r5, [r12, #11 * 4]	@ restore the original SVC vector entry

	mov	lr, r6			@ restore LR