From: Mark Rutland mark.rutland@arm.com
On Thu, Jul 11, 2013 at 04:10:51PM +0100, Hanjun Guo wrote:
Hi Mark,
Hi Hanjun,
I tested this patch set on the armv8 foundation model, it's panic.
I seems that we need to do something more, I'll also checkout what's going on here.
Thanks Hanjun
dump formation: root@genericarmv8:/sys/devices/system/cpu/cpu3# echo 0 > online CPU3: Booted secondary processor CPU3: shutdown BUG: failure at kernel/time/clockevents.c:284/clockevents_register_device()! Kernel panic - not syncing: BUG! CPU: 3 PID: 0 Comm: swapper/3 Not tainted 3.10.0+ #2 Call trace: [<ffffffc0000873e0>] dump_backtrace+0x0/0x12c [<ffffffc000087520>] show_stack+0x14/0x1c [<ffffffc0003f2e7c>] dump_stack+0x20/0x28 [<ffffffc0003efd24>] panic+0xe8/0x214 [<ffffffc0000d049c>] clockevents_set_mode+0x0/0x6c [<ffffffc0000d074c>] clockevents_config_and_register+0x24/0x30 [<ffffffc0003ef840>] arch_timer_setup+0xd8/0x140 [<ffffffc0003ef8f0>] arch_timer_cpu_notify+0x48/0xc8 [<ffffffc0000b83e4>] notifier_call_chain+0x48/0x88 [<ffffffc0000b8500>] __raw_notifier_call_chain+0xc/0x14 [<ffffffc0000973f0>] __cpu_notify+0x30/0x58 [<ffffffc00009742c>] cpu_notify+0x14/0x1c [<ffffffc0003ed46c>] notify_cpu_starting+0x14/0x1c [<ffffffc0003ece74>] secondary_start_kernel+0xc0/0xf4
That looks suspicious. It looks like the CPU didn't actually die and jumped immediately to secondary_start_kernel. At a guess, did you update your dts with a psci node and cpu enable-methods?
I can see the code's broken if you try hotplug with spin-table, because cpu_disable and cpu_die are both NULL, and the sanity checking doesn't attempt to deal with this case, so the cpu will end up getting into cpu_die, won't call anything, and jump straight back into the kernel. I'll fix up the op_cpu_disable checks to cover this.
The other possibility is that you're using PSCI but your function id for cpu_off is wrong, and thus the psci cpu_off call fails. Did you update your dts for PSCI? Below is a patch to do so.
Thanks, Mark. --- arch/arm64/boot/dts/foundation-v8.dts | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-)
diff --git a/arch/arm64/boot/dts/foundation-v8.dts b/arch/arm64/boot/dts/foundation-v8.dts index 84fcc50..335a88f 100644 --- a/arch/arm64/boot/dts/foundation-v8.dts +++ b/arch/arm64/boot/dts/foundation-v8.dts @@ -22,6 +22,13 @@ serial3 = &v2m_serial3; };
+ psci { + compatible = "arm,psci"; + method = "smc"; + cpu_off = <0x84000001>; + cpu_on = <0x84000002>; + }; + cpus { #address-cells = <2>; #size-cells = <0>; @@ -30,29 +37,25 @@ device_type = "cpu"; compatible = "arm,armv8"; reg = <0x0 0x0>; - enable-method = "spin-table"; - cpu-release-addr = <0x0 0x8000fff8>; + enable-method = "psci"; }; cpu@1 { device_type = "cpu"; compatible = "arm,armv8"; reg = <0x0 0x1>; - enable-method = "spin-table"; - cpu-release-addr = <0x0 0x8000fff8>; + enable-method = "psci"; }; cpu@2 { device_type = "cpu"; compatible = "arm,armv8"; reg = <0x0 0x2>; - enable-method = "spin-table"; - cpu-release-addr = <0x0 0x8000fff8>; + enable-method = "psci"; }; cpu@3 { device_type = "cpu"; compatible = "arm,armv8"; reg = <0x0 0x3>; - enable-method = "spin-table"; - cpu-release-addr = <0x0 0x8000fff8>; + enable-method = "psci"; }; };