When CONFIG_FSL_PMC is set to n, no value is assigned to cpu_up_prepare
in the mpc85xx_pm_ops structure. As a result, oops is triggered in
smp_85xx_start_cpu().
[ 0.627233] smp: Bringing up secondary CPUs ...
[ 0.681659] kernel tried to execute user page (0) - exploit attempt? (uid: 0)
[ 0.766618] BUG: Unable to handle kernel instruction fetch (NULL pointer?)
[ 0.848899] Faulting instruction address: 0x00000000
[ 0.908273] Oops: Kernel access of bad area, sig: 11 [#1]
...
[ 1.758220] NIP [00000000] 0x0
[ 1.794688] LR [c0021d2c] smp_85xx_kick_cpu+0xe8/0x568
[ 1.856126] Call Trace:
[ 1.885295] [c1051da8] [c0021cb8] smp_85xx_kick_cpu+0x74/0x568 (unreliable)
[ 1.968633] [c1051de8] [c0011460] __cpu_up+0xc0/0x228
[ 2.029038] [c1051e18] [c0031bbc] bringup_cpu+0x30/0x224
[ 2.092572] [c1051e48] [c0031f3c] cpu_up.constprop.0+0x180/0x33c
[ 2.164443] [c1051e88] [c00322e8] bringup_nonboot_cpus+0x88/0xc8
[ 2.236326] [c1051eb8] [c07e67bc] smp_init+0x30/0x78
[ 2.295698] [c1051ed8] [c07d9e28] kernel_init_freeable+0x118/0x2a8
[ 2.369641] [c1051f18] [c00032d8] kernel_init+0x14/0x124
[ 2.433176] [c1051f38] [c0010278] ret_from_kernel_thread+0x14/0x1c
Fixes: c45361abb9185b ("powerpc/85xx: fix timebase sync issue when
CONFIG_HOTPLUG_CPU=n")
Link: https://lore.kernel.org/lkml/CANA18Uyba4kMJQrbCSZVTFep2Exe5izE45whNJgwwUvNSEcNLg@xxxxxxxxxxxxxx/
Reported-by: Martin Kennedy <hurricos@xxxxxxxxx>
Signed-off-by: Xiaoming Ni <nixiaoming@xxxxxxxxxx>
Tested-by: Martin Kennedy <hurricos@xxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
---
arch/powerpc/platforms/85xx/smp.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/platforms/85xx/smp.c b/arch/powerpc/platforms/85xx/smp.c
index 83f4a6389a28..d7081e9af65c 100644
--- a/arch/powerpc/platforms/85xx/smp.c
+++ b/arch/powerpc/platforms/85xx/smp.c
@@ -220,7 +220,7 @@ static int smp_85xx_start_cpu(int cpu)
local_irq_save(flags);
hard_irq_disable();
- if (qoriq_pm_ops)
+ if (qoriq_pm_ops && qoriq_pm_ops->cpu_up_prepare)
qoriq_pm_ops->cpu_up_prepare(cpu);
/* if cpu is not spinning, reset it */
@@ -292,7 +292,7 @@ static int smp_85xx_kick_cpu(int nr)
booting_thread_hwid = cpu_thread_in_core(nr);
primary = cpu_first_thread_sibling(nr);
- if (qoriq_pm_ops)
+ if (qoriq_pm_ops && qoriq_pm_ops->cpu_up_prepare)
qoriq_pm_ops->cpu_up_prepare(nr);
/*
--
2.27.0
