From ecafe3e9b27644b51282b539878b7671ea28ac34 Mon Sep 17 00:00:00 2001 From: Paul Burton <paul.burton@imgtec.com> Date: Tue, 22 Sep 2015 11:58:43 -0700 Subject: [PATCH] MIPS: Malta: Register UP SMP ops if all else fails If we fail to register any real SMP implementations, fall back to registering the dummy UP implementation. Otherwise when we build an SMP kernel & run it on a system where the SMP implementations fail to probe (eg. QEMU) the kernel will perform a NULL dereference attempting to call mp_ops->smp_setup() from plat_smp_setup(). Notably this fixes booting kernels with CPS SMP enabled on QEMU, which doesn't currently implement the CM, CPC or GIC. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Rob Herring <robh@kernel.org> Cc: linux-kernel@vger.kernel.org Cc: Markos Chandras <markos.chandras@imgtec.com> Patchwork: https://patchwork.linux-mips.org/patch/11223/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org> --- arch/mips/Kconfig | 1 + arch/mips/mti-malta/malta-init.c | 1 + 2 files changed, 2 insertions(+) diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index 703438a9698e..9322d267e774 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -425,6 +425,7 @@ config MIPS_MALTA select MIPS_L1_CACHE_SHIFT_6 select PCI_GT64XXX_PCI0 select MIPS_MSC + select SMP_UP if SMP select SWAP_IO_SPACE select SYS_HAS_CPU_MIPS32_R1 select SYS_HAS_CPU_MIPS32_R2 diff --git a/arch/mips/mti-malta/malta-init.c b/arch/mips/mti-malta/malta-init.c index 53c24784a2f7..571148c5fd0b 100644 --- a/arch/mips/mti-malta/malta-init.c +++ b/arch/mips/mti-malta/malta-init.c @@ -302,6 +302,7 @@ void __init prom_init(void) return; if (!register_vsmp_smp_ops()) return; + register_up_smp_ops(); } void platform_early_l2_init(void)