4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eugeniy Paltsev <Eugeniy.Paltsev@xxxxxxxxxxxx> commit 252f6e8eae909bc075a1b1e3b9efb095ae4c0b56 upstream. It is currently done in arc_init_IRQ() which might be too late considering gcc 7.3.1 onwards (GNU 2018.03) generates unaligned memory accesses by default Cc: stable@xxxxxxxxxxxxxxx #4.4+ Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@xxxxxxxxxxxx> Signed-off-by: Vineet Gupta <vgupta@xxxxxxxxxxxx> [vgupta: rewrote changelog] Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/arc/kernel/head.S | 10 ++++++++++ 1 file changed, 10 insertions(+) --- a/arch/arc/kernel/head.S +++ b/arch/arc/kernel/head.S @@ -17,6 +17,7 @@ #include <asm/entry.h> #include <asm/arcregs.h> #include <asm/cache.h> +#include <asm/irqflags.h> .macro CPU_EARLY_SETUP @@ -47,6 +48,15 @@ sr r5, [ARC_REG_DC_CTRL] 1: + +#ifdef CONFIG_ISA_ARCV2 + ; Unaligned access is disabled at reset, so re-enable early as + ; gcc 7.3.1 (ARC GNU 2018.03) onwards generates unaligned access + ; by default + lr r5, [status32] + bset r5, r5, STATUS_AD_BIT + kflag r5 +#endif .endm .section .init.text, "ax",@progbits