linux-stable.git/drivers/cpuidle, branch linux-4.9.y Linux kernel stable tree cpuidle: dt: Return the correct numbers of parsed idle states 2023-01-07T11:07:13+00:00 Ulf Hansson ulf.hansson@linaro.org 2022-10-21T15:10:12+00:00 eea8631ca78e6cb7cc0dbe7a74559869ed4a967c [ Upstream commit ee3c2c8ad6ba6785f14a60e4081d7c82e88162a2 ] While we correctly skips to initialize an idle state from a disabled idle state node in DT, the returned value from dt_init_idle_driver() don't get adjusted accordingly. Instead the number of found idle state nodes are returned, while the callers are expecting the number of successfully initialized idle states from DT. This leads to cpuidle drivers unnecessarily continues to initialize their idle state specific data. Moreover, in the case when all idle states have been disabled in DT, we would end up registering a cpuidle driver, rather than relying on the default arch specific idle call. Fixes: 9f14da345599 ("drivers: cpuidle: implement DT based idle states infrastructure") Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit ee3c2c8ad6ba6785f14a60e4081d7c82e88162a2 ]

While we correctly skips to initialize an idle state from a disabled idle
state node in DT, the returned value from dt_init_idle_driver() don't get
adjusted accordingly. Instead the number of found idle state nodes are
returned, while the callers are expecting the number of successfully
initialized idle states from DT.

This leads to cpuidle drivers unnecessarily continues to initialize their
idle state specific data. Moreover, in the case when all idle states have
been disabled in DT, we would end up registering a cpuidle driver, rather
than relying on the default arch specific idle call.

Fixes: 9f14da345599 ("drivers: cpuidle: implement DT based idle states infrastructure")
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
cpuidle: Fix kobject memory leaks in error paths 2021-11-26T10:48:33+00:00 Anel Orazgaliyeva anelkz@amazon.de 2021-09-06T18:34:40+00:00 84d93e04986d415096b7b61f0010abade2ee250e [ Upstream commit e5f5a66c9aa9c331da5527c2e3fd9394e7091e01 ] Commit c343bf1ba5ef ("cpuidle: Fix three reference count leaks") fixes the cleanup of kobjects; however, it removes kfree() calls altogether, leading to memory leaks. Fix those and also defer the initialization of dev->kobj_dev until after the error check, so that we do not end up with a dangling pointer. Fixes: c343bf1ba5ef ("cpuidle: Fix three reference count leaks") Signed-off-by: Anel Orazgaliyeva <anelkz@amazon.de> Suggested-by: Aman Priyadarshi <apeureka@amazon.de> [ rjw: Subject edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit e5f5a66c9aa9c331da5527c2e3fd9394e7091e01 ]

Commit c343bf1ba5ef ("cpuidle: Fix three reference count leaks")
fixes the cleanup of kobjects; however, it removes kfree() calls
altogether, leading to memory leaks.

Fix those and also defer the initialization of dev->kobj_dev until
after the error check, so that we do not end up with a dangling
pointer.

Fixes: c343bf1ba5ef ("cpuidle: Fix three reference count leaks")
Signed-off-by: Anel Orazgaliyeva <anelkz@amazon.de>
Suggested-by: Aman Priyadarshi <apeureka@amazon.de>
[ rjw: Subject edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
cpuidle: Fix three reference count leaks 2020-06-20T08:24:18+00:00 Qiushi Wu wu000273@umn.edu 2020-05-28T18:20:46+00:00 42b548b9e9248ffd2f378bd4cbcb31d692ef3280 [ Upstream commit c343bf1ba5efcbf2266a1fe3baefec9cc82f867f ] kobject_init_and_add() takes reference even when it fails. If this function returns an error, kobject_put() must be called to properly clean up the memory associated with the object. Previous commit "b8eb718348b8" fixed a similar problem. Signed-off-by: Qiushi Wu <wu000273@umn.edu> [ rjw: Subject ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit c343bf1ba5efcbf2266a1fe3baefec9cc82f867f ]

kobject_init_and_add() takes reference even when it fails.
If this function returns an error, kobject_put() must be called to
properly clean up the memory associated with the object.

Previous commit "b8eb718348b8" fixed a similar problem.

Signed-off-by: Qiushi Wu <wu000273@umn.edu>
[ rjw: Subject ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
cpuidle: Do not unset the driver if it is there already 2019-12-21T09:42:04+00:00 Zhenzhong Duan zhenzhong.duan@oracle.com 2019-10-23T01:57:14+00:00 5751ba7db7d354dfdb491b9a83b24ea3d176d816 commit 918c1fe9fbbe46fcf56837ff21f0ef96424e8b29 upstream. Fix __cpuidle_set_driver() to check if any of the CPUs in the mask has a driver different from drv already and, if so, return -EBUSY before updating any cpuidle_drivers per-CPU pointers. Fixes: 82467a5a885d ("cpuidle: simplify multiple driver support") Cc: 3.11+ <stable@vger.kernel.org> # 3.11+ Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com> [ rjw: Subject & changelog ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 918c1fe9fbbe46fcf56837ff21f0ef96424e8b29 upstream.

Fix __cpuidle_set_driver() to check if any of the CPUs in the mask has
a driver different from drv already and, if so, return -EBUSY before
updating any cpuidle_drivers per-CPU pointers.

Fixes: 82467a5a885d ("cpuidle: simplify multiple driver support")
Cc: 3.11+ <stable@vger.kernel.org> # 3.11+
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
[ rjw: Subject & changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cpuidle: big.LITTLE: fix refcount leak 2019-02-12T18:44:55+00:00 Yangtao Li tiny.windzz@gmail.com 2018-12-10T16:26:41+00:00 da048fe9b871346d179d1f91122d9700e8b384d6 [ Upstream commit 9456823c842f346c74265fcd98d008d87a7eb6f5 ] of_find_node_by_path() acquires a reference to the node returned by it and that reference needs to be dropped by its caller. bl_idle_init() doesn't do that, so fix it. Signed-off-by: Yangtao Li <tiny.windzz@gmail.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 9456823c842f346c74265fcd98d008d87a7eb6f5 ]

of_find_node_by_path() acquires a reference to the node
returned by it and that reference needs to be dropped by its caller.
bl_idle_init() doesn't do that, so fix it.

Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
powerpc/pseries/cpuidle: Fix preempt warning 2019-01-26T08:38:33+00:00 Breno Leitao leitao@debian.org 2018-11-23T16:30:11+00:00 dc21489da678693c44a7feb8978c19006da30d3b [ Upstream commit 2b038cbc5fcf12a7ee1cc9bfd5da1e46dacdee87 ] When booting a pseries kernel with PREEMPT enabled, it dumps the following warning: BUG: using smp_processor_id() in preemptible [00000000] code: swapper/0/1 caller is pseries_processor_idle_init+0x5c/0x22c CPU: 13 PID: 1 Comm: swapper/0 Not tainted 4.20.0-rc3-00090-g12201a0128bc-dirty #828 Call Trace: [c000000429437ab0] [c0000000009c8878] dump_stack+0xec/0x164 (unreliable) [c000000429437b00] [c0000000005f2f24] check_preemption_disabled+0x154/0x160 [c000000429437b90] [c000000000cab8e8] pseries_processor_idle_init+0x5c/0x22c [c000000429437c10] [c000000000010ed4] do_one_initcall+0x64/0x300 [c000000429437ce0] [c000000000c54500] kernel_init_freeable+0x3f0/0x500 [c000000429437db0] [c0000000000112dc] kernel_init+0x2c/0x160 [c000000429437e20] [c00000000000c1d0] ret_from_kernel_thread+0x5c/0x6c This happens because the code calls get_lppaca() which calls get_paca() and it checks if preemption is disabled through check_preemption_disabled(). Preemption should be disabled because the per CPU variable may make no sense if there is a preemption (and a CPU switch) after it reads the per CPU data and when it is used. In this device driver specifically, it is not a problem, because this code just needs to have access to one lppaca struct, and it does not matter if it is the current per CPU lppaca struct or not (i.e. when there is a preemption and a CPU migration). That said, the most appropriate fix seems to be related to avoiding the debug_smp_processor_id() call at get_paca(), instead of calling preempt_disable() before get_paca(). Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 2b038cbc5fcf12a7ee1cc9bfd5da1e46dacdee87 ]

When booting a pseries kernel with PREEMPT enabled, it dumps the
following warning:

   BUG: using smp_processor_id() in preemptible [00000000] code: swapper/0/1
   caller is pseries_processor_idle_init+0x5c/0x22c
   CPU: 13 PID: 1 Comm: swapper/0 Not tainted 4.20.0-rc3-00090-g12201a0128bc-dirty #828
   Call Trace:
   [c000000429437ab0] [c0000000009c8878] dump_stack+0xec/0x164 (unreliable)
   [c000000429437b00] [c0000000005f2f24] check_preemption_disabled+0x154/0x160
   [c000000429437b90] [c000000000cab8e8] pseries_processor_idle_init+0x5c/0x22c
   [c000000429437c10] [c000000000010ed4] do_one_initcall+0x64/0x300
   [c000000429437ce0] [c000000000c54500] kernel_init_freeable+0x3f0/0x500
   [c000000429437db0] [c0000000000112dc] kernel_init+0x2c/0x160
   [c000000429437e20] [c00000000000c1d0] ret_from_kernel_thread+0x5c/0x6c

This happens because the code calls get_lppaca() which calls
get_paca() and it checks if preemption is disabled through
check_preemption_disabled().

Preemption should be disabled because the per CPU variable may make no
sense if there is a preemption (and a CPU switch) after it reads the
per CPU data and when it is used.

In this device driver specifically, it is not a problem, because this
code just needs to have access to one lppaca struct, and it does not
matter if it is the current per CPU lppaca struct or not (i.e. when
there is a preemption and a CPU migration).

That said, the most appropriate fix seems to be related to avoiding
the debug_smp_processor_id() call at get_paca(), instead of calling
preempt_disable() before get_paca().

Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
cpuidle: powernv: Fix promotion from snooze if next state disabled 2018-07-03T09:23:08+00:00 Gautham R. Shenoy ego@linux.vnet.ibm.com 2018-05-31T12:15:09+00:00 443004a666ede252f85bcdf8faab85d8174f0367 commit 0a4ec6aa035a52c422eceb2ed51ed88392a3d6c2 upstream. The commit 78eaa10f027c ("cpuidle: powernv/pseries: Auto-promotion of snooze to deeper idle state") introduced a timeout for the snooze idle state so that it could be eventually be promoted to a deeper idle state. The snooze timeout value is static and set to the target residency of the next idle state, which would train the cpuidle governor to pick the next idle state eventually. The unfortunate side-effect of this is that if the next idle state(s) is disabled, the CPU will forever remain in snooze, despite the fact that the system is completely idle, and other deeper idle states are available. This patch fixes the issue by dynamically setting the snooze timeout to the target residency of the next enabled state on the device. Before Patch: POWER8 : Only nap disabled. $ cpupower monitor sleep 30 sleep took 30.01297 seconds and exited with status 0 |Idle_Stats PKG |CORE|CPU | snoo | Nap | Fast 0| 8| 0| 96.41| 0.00| 0.00 0| 8| 1| 96.43| 0.00| 0.00 0| 8| 2| 96.47| 0.00| 0.00 0| 8| 3| 96.35| 0.00| 0.00 0| 8| 4| 96.37| 0.00| 0.00 0| 8| 5| 96.37| 0.00| 0.00 0| 8| 6| 96.47| 0.00| 0.00 0| 8| 7| 96.47| 0.00| 0.00 POWER9: Shallow states (stop0lite, stop1lite, stop2lite, stop0, stop1, stop2) disabled: $ cpupower monitor sleep 30 sleep took 30.05033 seconds and exited with status 0 |Idle_Stats PKG |CORE|CPU | snoo | stop | stop | stop | stop | stop | stop | stop | stop 0| 16| 0| 89.79| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00 0| 16| 1| 90.12| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00 0| 16| 2| 90.21| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00 0| 16| 3| 90.29| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00 After Patch: POWER8 : Only nap disabled. $ cpupower monitor sleep 30 sleep took 30.01200 seconds and exited with status 0 |Idle_Stats PKG |CORE|CPU | snoo | Nap | Fast 0| 8| 0| 16.58| 0.00| 77.21 0| 8| 1| 18.42| 0.00| 75.38 0| 8| 2| 4.70| 0.00| 94.09 0| 8| 3| 17.06| 0.00| 81.73 0| 8| 4| 3.06| 0.00| 95.73 0| 8| 5| 7.00| 0.00| 96.80 0| 8| 6| 1.00| 0.00| 98.79 0| 8| 7| 5.62| 0.00| 94.17 POWER9: Shallow states (stop0lite, stop1lite, stop2lite, stop0, stop1, stop2) disabled: $ cpupower monitor sleep 30 sleep took 30.02110 seconds and exited with status 0 |Idle_Stats PKG |CORE|CPU | snoo | stop | stop | stop | stop | stop | stop | stop | stop 0| 0| 0| 0.69| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 9.39| 89.70 0| 0| 1| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.05| 93.21 0| 0| 2| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 89.93 0| 0| 3| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 93.26 Fixes: 78eaa10f027c ("cpuidle: powernv/pseries: Auto-promotion of snooze to deeper idle state") Cc: stable@vger.kernel.org # v4.2+ Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Reviewed-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 0a4ec6aa035a52c422eceb2ed51ed88392a3d6c2 upstream.

The commit 78eaa10f027c ("cpuidle: powernv/pseries: Auto-promotion of
snooze to deeper idle state") introduced a timeout for the snooze idle
state so that it could be eventually be promoted to a deeper idle
state. The snooze timeout value is static and set to the target
residency of the next idle state, which would train the cpuidle
governor to pick the next idle state eventually.

The unfortunate side-effect of this is that if the next idle state(s)
is disabled, the CPU will forever remain in snooze, despite the fact
that the system is completely idle, and other deeper idle states are
available.

This patch fixes the issue by dynamically setting the snooze timeout
to the target residency of the next enabled state on the device.

Before Patch:
  POWER8 : Only nap disabled.
  $ cpupower monitor sleep 30
  sleep took 30.01297 seconds and exited with status 0
                |Idle_Stats
  PKG |CORE|CPU | snoo | Nap  | Fast
     0|   8|   0| 96.41|  0.00|  0.00
     0|   8|   1| 96.43|  0.00|  0.00
     0|   8|   2| 96.47|  0.00|  0.00
     0|   8|   3| 96.35|  0.00|  0.00
     0|   8|   4| 96.37|  0.00|  0.00
     0|   8|   5| 96.37|  0.00|  0.00
     0|   8|   6| 96.47|  0.00|  0.00
     0|   8|   7| 96.47|  0.00|  0.00

  POWER9: Shallow states (stop0lite, stop1lite, stop2lite, stop0, stop1,
  stop2) disabled:
  $ cpupower monitor sleep 30
  sleep took 30.05033 seconds and exited with status 0
                |Idle_Stats
  PKG |CORE|CPU | snoo | stop | stop | stop | stop | stop | stop | stop | stop
     0|  16|   0| 89.79|  0.00|  0.00|  0.00|  0.00|  0.00|  0.00|  0.00|  0.00
     0|  16|   1| 90.12|  0.00|  0.00|  0.00|  0.00|  0.00|  0.00|  0.00|  0.00
     0|  16|   2| 90.21|  0.00|  0.00|  0.00|  0.00|  0.00|  0.00|  0.00|  0.00
     0|  16|   3| 90.29|  0.00|  0.00|  0.00|  0.00|  0.00|  0.00|  0.00|  0.00

After Patch:
  POWER8 : Only nap disabled.
  $ cpupower monitor sleep 30
  sleep took 30.01200 seconds and exited with status 0
                |Idle_Stats
  PKG |CORE|CPU | snoo | Nap  | Fast
     0|   8|   0| 16.58|  0.00| 77.21
     0|   8|   1| 18.42|  0.00| 75.38
     0|   8|   2|  4.70|  0.00| 94.09
     0|   8|   3| 17.06|  0.00| 81.73
     0|   8|   4|  3.06|  0.00| 95.73
     0|   8|   5|  7.00|  0.00| 96.80
     0|   8|   6|  1.00|  0.00| 98.79
     0|   8|   7|  5.62|  0.00| 94.17

  POWER9: Shallow states (stop0lite, stop1lite, stop2lite, stop0, stop1,
  stop2) disabled:

  $ cpupower monitor sleep 30
  sleep took 30.02110 seconds and exited with status 0
                |Idle_Stats
  PKG |CORE|CPU | snoo | stop | stop | stop | stop | stop | stop | stop | stop
     0|   0|   0|  0.69|  0.00|  0.00|  0.00|  0.00|  0.00|  0.00|  9.39| 89.70
     0|   0|   1|  0.00|  0.00|  0.00|  0.00|  0.00|  0.00|  0.00|  0.05| 93.21
     0|   0|   2|  0.00|  0.00|  0.00|  0.00|  0.00|  0.00|  0.00|  0.00| 89.93
     0|   0|   3|  0.00|  0.00|  0.00|  0.00|  0.00|  0.00|  0.00|  0.00| 93.26

Fixes: 78eaa10f027c ("cpuidle: powernv/pseries: Auto-promotion of snooze to deeper idle state")
Cc: stable@vger.kernel.org # v4.2+
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Reviewed-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cpuidle: dt: Add missing 'of_node_put()' 2018-04-13T17:48:28+00:00 Christophe Jaillet christophe.jaillet@wanadoo.fr 2017-06-11T12:28:54+00:00 b22081fbfbaac0016fec3c087216ec11adba64d3 [ Upstream commit b2cdd8e1b54849477a32d820acc2e87828a38f3d ] 'of_node_put()' should be called on pointer returned by 'of_parse_phandle()' when done. In this function this is done in all path except this 'continue', so add it. Fixes: 97735da074fd (drivers: cpuidle: Add status property to ARM idle states) Signed-off-by: Christophe Jaillet <christophe.jaillet@wanadoo.fr> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit b2cdd8e1b54849477a32d820acc2e87828a38f3d ]

'of_node_put()' should be called on pointer returned by
'of_parse_phandle()' when done. In this function this is done in all path
except this 'continue', so add it.

Fixes: 97735da074fd (drivers: cpuidle: Add status property to ARM idle states)
Signed-off-by: Christophe Jaillet <christophe.jaillet@wanadoo.fr>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cpuidle: fix broadcast control when broadcast can not be entered 2017-12-25T13:23:46+00:00 Nicholas Piggin npiggin@gmail.com 2017-09-01T04:29:56+00:00 b86c7b8c5dfb2a68bce79e1ad3fe50e06022d1f6 [ Upstream commit f187851b9b4a76952b1158b86434563dd2031103 ] When failing to enter broadcast timer mode for an idle state that requires it, a new state is selected that does not require broadcast, but the broadcast variable remains set. This causes tick_broadcast_exit to be called despite not having entered broadcast mode. This causes the WARN_ON_ONCE(!irqs_disabled()) to trigger in some cases. It does not appear to cause problems for code today, but seems to violate the interface so should be fixed. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit f187851b9b4a76952b1158b86434563dd2031103 ]

When failing to enter broadcast timer mode for an idle state that
requires it, a new state is selected that does not require broadcast,
but the broadcast variable remains set. This causes
tick_broadcast_exit to be called despite not having entered broadcast
mode.

This causes the WARN_ON_ONCE(!irqs_disabled()) to trigger in some
cases. It does not appear to cause problems for code today, but seems
to violate the interface so should be fixed.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cpuidle: powernv: Pass correct drv->cpumask for registration 2017-12-25T13:23:43+00:00 Vaidyanathan Srinivasan svaidy@linux.vnet.ibm.com 2017-03-23T15:22:46+00:00 9e1771368a9835ba21999bebf58496428d7d5443 [ Upstream commit 293d264f13cbde328d5477f49e3103edbc1dc191 ] drv->cpumask defaults to cpu_possible_mask in __cpuidle_driver_init(). On PowerNV platform cpu_present could be less than cpu_possible in cases where firmware detects the cpu, but it is not available to the OS. When CONFIG_HOTPLUG_CPU=n, such cpus are not hotplugable at runtime and hence we skip creating cpu_device. This breaks cpuidle on powernv where register_cpu() is not called for cpus in cpu_possible_mask that cannot be hot-added at runtime. Trying cpuidle_register_device() on cpu without cpu_device will cause crash like this: cpu 0xf: Vector: 380 (Data SLB Access) at [c000000ff1503490] pc: c00000000022c8bc: string+0x34/0x60 lr: c00000000022ed78: vsnprintf+0x284/0x42c sp: c000000ff1503710 msr: 9000000000009033 dar: 6000000060000000 current = 0xc000000ff1480000 paca = 0xc00000000fe82d00 softe: 0 irq_happened: 0x01 pid = 1, comm = swapper/8 Linux version 4.11.0-rc2 (sv@sagarika) (gcc version 4.9.4 (Buildroot 2017.02-00004-gc28573e) ) #15 SMP Fri Mar 17 19:32:02 IST 2017 enter ? for help [link register ] c00000000022ed78 vsnprintf+0x284/0x42c [c000000ff1503710] c00000000022ebb8 vsnprintf+0xc4/0x42c (unreliable) [c000000ff1503800] c00000000022ef40 vscnprintf+0x20/0x44 [c000000ff1503830] c0000000000ab61c vprintk_emit+0x94/0x2cc [c000000ff15038a0] c0000000000acc9c vprintk_func+0x60/0x74 [c000000ff15038c0] c000000000619694 printk+0x38/0x4c [c000000ff15038e0] c000000000224950 kobject_get+0x40/0x60 [c000000ff1503950] c00000000022507c kobject_add_internal+0x60/0x2c4 [c000000ff15039e0] c000000000225350 kobject_init_and_add+0x70/0x78 [c000000ff1503a60] c00000000053c288 cpuidle_add_sysfs+0x9c/0xe0 [c000000ff1503ae0] c00000000053aeac cpuidle_register_device+0xd4/0x12c [c000000ff1503b30] c00000000053b108 cpuidle_register+0x98/0xcc [c000000ff1503bc0] c00000000085eaf0 powernv_processor_idle_init+0x140/0x1e0 [c000000ff1503c60] c00000000000cd60 do_one_initcall+0xc0/0x15c [c000000ff1503d20] c000000000833e84 kernel_init_freeable+0x1a0/0x25c [c000000ff1503dc0] c00000000000d478 kernel_init+0x24/0x12c [c000000ff1503e30] c00000000000b564 ret_from_kernel_thread+0x5c/0x78 This patch fixes the bug by passing correct cpumask from powernv-cpuidle driver. Signed-off-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com> Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> [ rjw: Comment massage ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 293d264f13cbde328d5477f49e3103edbc1dc191 ]

drv->cpumask defaults to cpu_possible_mask in __cpuidle_driver_init().
On PowerNV platform cpu_present could be less than cpu_possible in cases
where firmware detects the cpu, but it is not available to the OS.  When
CONFIG_HOTPLUG_CPU=n, such cpus are not hotplugable at runtime and hence
we skip creating cpu_device.

This breaks cpuidle on powernv where register_cpu() is not called for
cpus in cpu_possible_mask that cannot be hot-added at runtime.

Trying cpuidle_register_device() on cpu without cpu_device will cause
crash like this:

cpu 0xf: Vector: 380 (Data SLB Access) at [c000000ff1503490]
    pc: c00000000022c8bc: string+0x34/0x60
    lr: c00000000022ed78: vsnprintf+0x284/0x42c
    sp: c000000ff1503710
   msr: 9000000000009033
   dar: 6000000060000000
  current = 0xc000000ff1480000
  paca    = 0xc00000000fe82d00   softe: 0        irq_happened: 0x01
    pid   = 1, comm = swapper/8
Linux version 4.11.0-rc2 (sv@sagarika) (gcc version 4.9.4
(Buildroot 2017.02-00004-gc28573e) ) #15 SMP Fri Mar 17 19:32:02 IST 2017
enter ? for help
[link register   ] c00000000022ed78 vsnprintf+0x284/0x42c
[c000000ff1503710] c00000000022ebb8 vsnprintf+0xc4/0x42c (unreliable)
[c000000ff1503800] c00000000022ef40 vscnprintf+0x20/0x44
[c000000ff1503830] c0000000000ab61c vprintk_emit+0x94/0x2cc
[c000000ff15038a0] c0000000000acc9c vprintk_func+0x60/0x74
[c000000ff15038c0] c000000000619694 printk+0x38/0x4c
[c000000ff15038e0] c000000000224950 kobject_get+0x40/0x60
[c000000ff1503950] c00000000022507c kobject_add_internal+0x60/0x2c4
[c000000ff15039e0] c000000000225350 kobject_init_and_add+0x70/0x78
[c000000ff1503a60] c00000000053c288 cpuidle_add_sysfs+0x9c/0xe0
[c000000ff1503ae0] c00000000053aeac cpuidle_register_device+0xd4/0x12c
[c000000ff1503b30] c00000000053b108 cpuidle_register+0x98/0xcc
[c000000ff1503bc0] c00000000085eaf0 powernv_processor_idle_init+0x140/0x1e0
[c000000ff1503c60] c00000000000cd60 do_one_initcall+0xc0/0x15c
[c000000ff1503d20] c000000000833e84 kernel_init_freeable+0x1a0/0x25c
[c000000ff1503dc0] c00000000000d478 kernel_init+0x24/0x12c
[c000000ff1503e30] c00000000000b564 ret_from_kernel_thread+0x5c/0x78

This patch fixes the bug by passing correct cpumask from
powernv-cpuidle driver.

Signed-off-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
[ rjw: Comment massage ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>