4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: James Morse <james.morse@xxxxxxx> commit a6002ec5a8c68e69706b2efd6db6d682d0ab672c upstream. arm and arm64 use different config options to specify big endian. This needs taking into account when including code/headers between the two architectures. A case in point is PAN, which uses the __instr_arm() macro to output instructions. The macro comes from opcodes.h, which lives under arch/arm. On a big-endian build the mismatched config options mean the instruction isn't byte swapped correctly, resulting in undefined instruction exceptions during boot: | alternatives: patching kernel code | kdevtmpfs[87]: undefined instruction: pc=ffffffc0004505b4 | kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c | kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c | kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c | kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c | kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c | kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c | kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c | kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c | kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c | Internal error: Oops - undefined instruction: 0 [#1] SMP | Modules linked in: | CPU: 0 PID: 87 Comm: kdevtmpfs Not tainted 4.1.16+ #5 | Hardware name: Hisilicon PhosphorHi1382 EVB (DT) | task: ffffffc336591700 ti: ffffffc3365a4000 task.ti: ffffffc3365a4000 | PC is at dump_instr+0x68/0x100 | LR is at do_undefinstr+0x1d4/0x2a4 | pc : [<ffffffc00076231c>] lr : [<ffffffc0000811d4>] pstate: 604001c5 | sp : ffffffc3365a6450 Reported-by: Hanjun Guo <guohanjun@xxxxxxxxxx> Tested-by: Xuefeng Wang <wxf.wang@xxxxxxxxxxxxx> Signed-off-by: James Morse <james.morse@xxxxxxx> Signed-off-by: Will Deacon <will.deacon@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/arm64/include/asm/opcodes.h | 4 ++++ 1 file changed, 4 insertions(+) --- a/arch/arm64/include/asm/opcodes.h +++ b/arch/arm64/include/asm/opcodes.h @@ -1 +1,5 @@ +#ifdef CONFIG_CPU_BIG_ENDIAN +#define CONFIG_CPU_ENDIAN_BE8 CONFIG_CPU_BIG_ENDIAN +#endif + #include <../../arm/include/asm/opcodes.h> -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html