linux/drivers/cpuidle
Vaidyanathan Srinivasan ad0a45fd9c cpuidle: Validate cpu_dev in cpuidle_add_sysfs()
If a given cpu is not in cpu_present and cpu hotplug
is disabled, arch can skip setting up the cpu_dev.

Arch cpuidle driver should pass correct cpu mask
for registration, but failing to do so by the driver
causes error to propagate and crash like this:

[   30.076045] Unable to handle kernel paging request for data at address 0x00000048
[   30.076100] Faulting instruction address: 0xc0000000007b2f30
cpu 0x4d: Vector: 300 (Data Access) at [c000003feb18b670]
    pc: c0000000007b2f30: kobject_get+0x20/0x70
    lr: c0000000007b3c94: kobject_add_internal+0x54/0x3f0
    sp: c000003feb18b8f0
   msr: 9000000000009033
   dar: 48
 dsisr: 40000000
  current = 0xc000003fd2ed8300
  paca    = 0xc00000000fbab500   softe: 0        irq_happened: 0x01
    pid   = 1, comm = swapper/0
Linux version 4.11.0-rc2-svaidy+ (sv@sagarika) (gcc version 6.2.0
20161005 (Ubuntu 6.2.0-5ubuntu12) ) #10 SMP Sun Mar 19 00:08:09 IST 2017
enter ? for help
[c000003feb18b960] c0000000007b3c94 kobject_add_internal+0x54/0x3f0
[c000003feb18b9f0] c0000000007b43a4 kobject_init_and_add+0x64/0xa0
[c000003feb18ba70] c000000000e284f4 cpuidle_add_sysfs+0xb4/0x130
[c000003feb18baf0] c000000000e26038 cpuidle_register_device+0x118/0x1c0
[c000003feb18bb30] c000000000e26c48 cpuidle_register+0x78/0x120
[c000003feb18bbc0] c00000000168fd9c powernv_processor_idle_init+0x110/0x1c4
[c000003feb18bc40] c00000000000cff8 do_one_initcall+0x68/0x1d0
[c000003feb18bd00] c0000000016242f4 kernel_init_freeable+0x280/0x360
[c000003feb18bdc0] c00000000000d864 kernel_init+0x24/0x160
[c000003feb18be30] c00000000000b4e8 ret_from_kernel_thread+0x5c/0x74

Validating cpu_dev fixes the crash and reports correct error message like:

[   30.163506] Failed to register cpuidle device for cpu136
[   30.173329] Registration of powernv driver failed.

Signed-off-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
[ rjw: Comment massage ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-03-21 22:26:37 +01:00
..
governors Merge branch 'WIP.sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-03-03 10:16:38 -08:00
coupled.c cpuidle/coupled: Convert to hotplug state machine 2016-09-06 18:30:24 +02:00
cpuidle-arm.c Merge branches 'pm-cpuidle', 'pm-opp' and 'pm-avs' 2016-10-02 01:43:16 +02:00
cpuidle-at91.c
cpuidle-big_little.c
cpuidle-calxeda.c ARM: migrate to common PSCI client code 2015-08-03 15:38:39 +01:00
cpuidle-clps711x.c drivers/cpuidle: make cpuidle-clps711x.c explicitly non-modular 2015-12-15 00:22:21 +01:00
cpuidle-cps.c cpuidle: cpuidle-cps: Enable use with MIPSr6 CPUs. 2016-10-04 16:13:57 +02:00
cpuidle-exynos.c drivers/cpuidle: make cpuidle-exynos.c explicitly non-modular 2015-12-15 00:22:22 +01:00
cpuidle-kirkwood.c
cpuidle-mvebu-v7.c cpuidle: mvebu: disable the bind/unbind attributes and use builtin_platform_driver 2015-10-23 12:40:48 +02:00
cpuidle-powernv.c powernv: Pass PSSCR value and mask to power9_idle_stop 2017-01-31 08:32:13 +11:00
cpuidle-pseries.c cpuidle/pseries: Convert to hotplug state machine 2016-09-06 18:30:24 +02:00
cpuidle-ux500.c drivers/cpuidle: make cpuidle-ux500.c explicitly non-modular 2015-12-15 00:22:22 +01:00
cpuidle-zynq.c
cpuidle.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/clock.h> 2017-03-02 08:42:27 +01:00
cpuidle.h cpuidle/coupled: Add sanity check for safe_state_index 2015-09-03 03:05:47 +02:00
driver.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/idle.h> 2017-03-02 08:42:26 +01:00
dt_idle_states.c cpuidle: dt: assign ->enter_freeze to same as ->enter callback function 2016-11-23 02:03:11 +01:00
dt_idle_states.h
governor.c cpuidle: governors: Remove remaining old module code 2016-10-21 14:49:51 +02:00
Kconfig cpuidle: Don't enable all governors by default 2016-01-15 22:39:58 +01:00
Kconfig.arm
Kconfig.mips cpuidle: cpuidle-cps: Enable use with MIPSr6 CPUs. 2016-10-04 16:13:57 +02:00
Kconfig.powerpc
Makefile
sysfs.c cpuidle: Validate cpu_dev in cpuidle_add_sysfs() 2017-03-21 22:26:37 +01:00