* pm-domains:
PM / Domains: Add DT file to MAINTAINERS
PM / Domains: Fix DT example
* pm-cpuidle:
x86/intel_idle: add Gemini Lake support
cpuidle: check dev before usage in cpuidle_use_deepest_state()
* pm-sleep:
ACPI / sleep: Ignore spurious SCI wakeups from suspend-to-idle
PM / wakeup: Integrate mechanism to abort transitions in progress
* powercap:
powercap: intel_rapl: Add support for Gemini Lake
In case of there is no cpuidle devices registered, dev will be null, and
panic will be triggered like below;
In this patch, add checking of dev before usage, like that done in
cpuidle_idle_call.
Panic without fix:
[ 184.961328] BUG: unable to handle kernel NULL pointer dereference at
(null)
[ 184.961328] IP: cpuidle_use_deepest_state+0x30/0x60
...
[ 184.961328] play_idle+0x8d/0x210
[ 184.961328] ? __schedule+0x359/0x8e0
[ 184.961328] ? _raw_spin_unlock_irqrestore+0x28/0x50
[ 184.961328] ? kthread_queue_delayed_work+0x41/0x80
[ 184.961328] clamp_idle_injection_func+0x64/0x1e0
Fixes: bb8313b603 (cpuidle: Allow enforcing deepest idle state selection)
Signed-off-by: Li, Fei <fei.li@intel.com>
Tested-by: Shi, Feng <fengx.shi@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: 4.10+ <stable@vger.kernel.org> # 4.10+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
When in the snooze_loop() we want to take up the least amount of
resources. On my version of gcc (6.3), we end up with an extra
branch because it predicts snooze_timeout_en to be false, whereas it
is almost always true.
Use likely() to avoid the branch and be a little nicer to the
other non idle threads on the core.
Signed-off-by: Anton Blanchard <anton@samba.org>
Reviewed-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The powerpc64 kernel exception handlers have preserved thread priorities
for a long time now, so there is no need to continually set it.
Just set it once on entry and once exit.
Signed-off-by: Anton Blanchard <anton@samba.org>
Reviewed-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The core of snooze_loop() continually bounces between low and very
low thread priority. Changing thread priorities is an expensive
operation that can negatively impact other threads on a core.
All CPUs that can run PowerNV support very low priority, so we can
avoid the change completely.
Signed-off-by: Anton Blanchard <anton@samba.org>
Reviewed-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
'core' in cps_cpuidle_init has never been used and is unnecessary, so
remove the dead code.
Signed-off-by: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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>
The various properties associated with powernv idle states such as
names, flags, residency-ns, latencies-ns, psscr, psscr-mask are
exposed in the device-tree as property arrays such the pointwise
entries in each of these arrays correspond to the properties of the
same idle state.
This patch validates that the lengths of the property arrays are the
same. If there is a mismatch, the patch will ensure that we bail out
and not expose the platform idle states via cpuidle.
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Reviewed-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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>
Pull sched.h split-up from Ingo Molnar:
"The point of these changes is to significantly reduce the
<linux/sched.h> header footprint, to speed up the kernel build and to
have a cleaner header structure.
After these changes the new <linux/sched.h>'s typical preprocessed
size goes down from a previous ~0.68 MB (~22K lines) to ~0.45 MB (~15K
lines), which is around 40% faster to build on typical configs.
Not much changed from the last version (-v2) posted three weeks ago: I
eliminated quirks, backmerged fixes plus I rebased it to an upstream
SHA1 from yesterday that includes most changes queued up in -next plus
all sched.h changes that were pending from Andrew.
I've re-tested the series both on x86 and on cross-arch defconfigs,
and did a bisectability test at a number of random points.
I tried to test as many build configurations as possible, but some
build breakage is probably still left - but it should be mostly
limited to architectures that have no cross-compiler binaries
available on kernel.org, and non-default configurations"
* 'WIP.sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (146 commits)
sched/headers: Clean up <linux/sched.h>
sched/headers: Remove #ifdefs from <linux/sched.h>
sched/headers: Remove the <linux/topology.h> include from <linux/sched.h>
sched/headers, hrtimer: Remove the <linux/wait.h> include from <linux/hrtimer.h>
sched/headers, x86/apic: Remove the <linux/pm.h> header inclusion from <asm/apic.h>
sched/headers, timers: Remove the <linux/sysctl.h> include from <linux/timer.h>
sched/headers: Remove <linux/magic.h> from <linux/sched/task_stack.h>
sched/headers: Remove <linux/sched.h> from <linux/sched/init.h>
sched/core: Remove unused prefetch_stack()
sched/headers: Remove <linux/rculist.h> from <linux/sched.h>
sched/headers: Remove the 'init_pid_ns' prototype from <linux/sched.h>
sched/headers: Remove <linux/signal.h> from <linux/sched.h>
sched/headers: Remove <linux/rwsem.h> from <linux/sched.h>
sched/headers: Remove the runqueue_is_locked() prototype
sched/headers: Remove <linux/sched.h> from <linux/sched/hotplug.h>
sched/headers: Remove <linux/sched.h> from <linux/sched/debug.h>
sched/headers: Remove <linux/sched.h> from <linux/sched/nohz.h>
sched/headers: Remove <linux/sched.h> from <linux/sched/stat.h>
sched/headers: Remove the <linux/gfp.h> include from <linux/sched.h>
sched/headers: Remove <linux/rtmutex.h> from <linux/sched.h>
...
Pull more power management updates deom Rafael Wysocki:
"These fix two bugs introduced by recent power management updates (in
the cpuidle menu governor and intel_pstate) and a few other issues,
clean up things and remove unused code.
Specifics:
- Fix for a cpuidle menu governor problem that started to take an
unnecessary spinlock after one of the recent updates and that did
not play well with the RT patch (Rafael Wysocki).
- Fix for the new intel_pstate operation mode switching feature added
recently that did not reinitialize P-state limits properly when
switching operation modes (Rafael Wysocki).
- Removal of unused global notifiers from the PM QoS framework
(Viresh Kumar).
- Generic power domains framework update to make it handle
asynchronous invocations of PM callbacks in the "noirq" phases of
system suspend/hibernation correctly (Ulf Hansson).
- Two hibernation core cleanups (Rafael Wysocki).
- intel_idle cleanup related to the sysfs interface (Len Brown).
- Off-by-one bug fix in the OPP (Operating Performance Points)
framework (Andrzej Hajda).
- OPP framework's documentation fix (Viresh Kumar).
- cpufreq qoriq driver cleanup (Tang Yuantian).
- Fixes for typos in comments in the device runtime PM framework
(Christophe Jaillet)"
* tag 'pm-extra-4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM / OPP: Documentation: Fix opp-microvolt in examples
intel_idle: stop exposing platform acronyms in sysfs
cpufreq: intel_pstate: Fix limits issue with operation mode switching
PM / hibernate: Define pr_fmt() and use pr_*() instead of printk()
PM / hibernate: Untangle power_down()
cpuidle: menu: Avoid taking spinlock for accessing QoS values
PM / QoS: Remove global notifiers
PM / runtime: Fix some typos
cpufreq: qoriq: clean up unused code
PM / OPP: fix off-by-one bug in dev_pm_opp_get_max_volt_latency loop
PM / Domains: Power off masters immediately in the power off sequence
PM / Domains: Rename is_async to one_dev_on for genpd_power_off()
PM / Domains: Move genpd_power_off() above genpd_power_on()
We are going to split <linux/sched/stat.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.
Create a trivial placeholder <linux/sched/stat.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.
Include the new header in the files that are going to need it.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We are going to split <linux/sched/loadavg.h> out of <linux/sched.h>, which
will have to be picked up from a couple of .c files.
Create a trivial placeholder <linux/sched/topology.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.
Include the new header in the files that are going to need it.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We are going to split <linux/sched/clock.h> out of <linux/sched.h>, which
will have to be picked up from other headers and .c files.
Create a trivial placeholder <linux/sched/clock.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.
Include the new header in the files that are going to need it.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We are going to split <linux/sched/idle.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.
Create a trivial placeholder <linux/sched/idle.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.
Include the new header in the files that are going to need it.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
After commit 9908859aca (cpuidle/menu: add per CPU PM QoS resume
latency consideration) the cpuidle menu governor calls
dev_pm_qos_read_value() on CPU devices to read the current resume
latency QoS constraint values for them. That function takes a spinlock
to prevent the device's power.qos pointer from becoming NULL during
the access which is a problem for the RT patchset where spinlocks are
converted into mutexes and the idle loop stops working.
However, it is not even necessary for the menu governor to take
that spinlock, because the power.qos pointer accessed under it
cannot be modified during the access anyway.
For this reason, introduce a "raw" routine for accessing device
QoS resume latency constraints without locking and use it in the
menu governor.
Fixes: 9908859aca (cpuidle/menu: add per CPU PM QoS resume latency consideration)
Acked-by: Alex Shi <alex.shi@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Pull powerpc updates from Michael Ellerman:
"Highlights include:
- Support for direct mapped LPC on POWER9, giving Linux direct access
to devices that may be on there such as a UART.
- Memory hotplug support for the Power9 Radix MMU.
- Add new AUX vectors describing the processor's cache geometry, to
be used by glibc.
- The ability for a guest to ask the hypervisor to resize the guest's
hash table, and in addition support for doing so automatically when
memory is hotplugged into/out-of the guest. This allows the hash
table to be sized based on the current memory usage of the guest,
rather than the maximum possible memory usage.
- Implementation of optprobes (kprobe optimisation) for powerpc.
In addition there's the topic branch shared with the KVM tree, which
includes support for guests to use the Radix MMU on Power9.
Thanks to:
Alistair Popple, Andrew Donnellan, Aneesh Kumar K.V, Anju T, Anton
Blanchard, Benjamin Herrenschmidt, Chris Packham, Daniel Axtens,
Daniel Borkmann, David Gibson, Finn Thain, Gautham R. Shenoy, Gavin
Shan, Greg Kurz, Joel Stanley, John Allen, Madhavan Srinivasan,
Mahesh Salgaonkar, Markus Elfring, Michael Neuling, Nathan Fontenot,
Naveen N. Rao, Nicholas Piggin, Paul Mackerras, Ravi Bangoria, Reza
Arbab, Shailendra Singh, Vaibhav Jain, Wei Yongjun"
* tag 'powerpc-4.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (129 commits)
powerpc/mm/radix: Skip ptesync in pte update helpers
powerpc/mm/radix: Use ptep_get_and_clear_full when clearing pte for full mm
powerpc/mm/radix: Update pte update sequence for pte clear case
powerpc/mm: Update PROTFAULT handling in the page fault path
powerpc/xmon: Fix data-breakpoint
powerpc/mm: Fix build break with BOOK3S_64=n and MEMORY_HOTPLUG=y
powerpc/mm: Fix build break when CMA=n && SPAPR_TCE_IOMMU=y
powerpc/mm: Fix build break with RADIX=y & HUGETLBFS=n
powerpc/pseries: Fix typo in parameter description
powerpc/kprobes: Remove kprobe_exceptions_notify()
kprobes: Introduce weak variant of kprobe_exceptions_notify()
powerpc/ftrace: Fix confusing help text for DISABLE_MPROFILE_KERNEL
powerpc/powernv: Fix opal_exit tracepoint opcode
powerpc: Add a prototype for mcount() so it can be versioned
powerpc: Drop GPL from of_node_to_nid() export to match other arches
powerpc/kprobes: Optimize kprobe in kretprobe_trampoline()
powerpc/kprobes: Implement Optprobes
powerpc/kprobes: Fixes for kprobe_lookup_name() on BE
powerpc: Add helper to check if offset is within relative branch range
powerpc/bpf: Introduce __PPC_SH64()
...
The power9_idle_stop method currently takes only the requested stop
level as a parameter and picks up the rest of the PSSCR bits from a
hand-coded macro. This is not a very flexible design, especially when
the firmware has the capability to communicate the psscr value and the
mask associated with a particular stop state via device tree.
This patch modifies the power9_idle_stop API to take as parameters the
PSSCR value and the PSSCR mask corresponding to the stop state that
needs to be set. These PSSCR value and mask are respectively obtained
by parsing the "ibm,cpu-idle-state-psscr" and
"ibm,cpu-idle-state-psscr-mask" fields from the device tree.
In addition to this, the patch adds support for handling stop states
for which ESL and EC bits in the PSSCR are zero. As per the
architecture, a wakeup from these stop states resumes execution from
the subsequent instruction as opposed to waking up at the System
Vector.
The older firmware sets only the Requested Level (RL) field in the
psscr and psscr-mask exposed in the device tree. For older firmware
where psscr-mask=0xf, this patch will set the default sane values that
the set for for remaining PSSCR fields (i.e PSLL, MTL, ESL, EC, and
TR). For the new firmware, the patch will validate that the invariants
required by the ISA for the psscr values are maintained by the
firmware.
This skiboot patch that exports fully populated PSSCR values and the
mask for all the stop states can be found here:
https://lists.ozlabs.org/pipermail/skiboot/2016-September/004869.html
[Optimize the number of instructions before entering STOP with
ESL=EC=0, validate the PSSCR values provided by the firimware
maintains the invariants required as per the ISA suggested by Balbir
Singh]
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
In the current code for powernv_add_idle_states, there is a lot of code
duplication while initializing an idle state in powernv_states table.
Add an inline helper function to populate the powernv_states[] table
for a given idle state. Invoke this for populating the "Nap",
"Fastsleep" and the stop states in powernv_add_idle_states.
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
There may be special requirements on CPU response time, like if a
interrupt is pinned to a CPU, that CPU should not go into excessively
deep idle states. For this reason, add a mechanism for adding
PM QoS resume latency constraints for individual CPUs and modify the
menu governor to take them into account.
To that end, extend the device PM QoS pm_qos_resume_latency attribute
to CPUs, which is possible, because the exit latency for CPUs is
effectively equivalent to the resume latency for devices.
Signed-off-by: Alex Shi <alex.shi@linaro.org>
Acked-by: Rik van Riel <riel@redhat.com>
[ rjw : Subject & changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Obsolete commit 71abbbf856 (cpuidle: extend cpuidle and menu governor
to handle dynamic states) wanted to introduce dynamic C-states, but that
idea was dropped long ago. The nonsense deeper C-state checking
remained, though.
Since both target_residency and exit_latency are longer for deeper
idle state, there's no need to waste CPU time on useless checks.
Signed-off-by: Alex Shi <alex.shi@linaro.org>
Acked-by: Rik van Riel <riel@redhat.com>
[ rjw: Subject & changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This was entirely automated, using the script by Al:
PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)
to do the replacement at the end of the merge window.
Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since cpuidle_use_deepest_state() is not static, add a proper
kerneldoc comment to it to document its purpose.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In function cpuidle_add_state_sysfs(), variable ret takes the return
value. Its value should be negative on errors. Because ret is reset in
the loop, its value will be 0 during the second and after repeat of the
loop. If kzalloc() returns a NULL pointer then, it will return 0. It may
be better to explicitly assign "-ENOMEM" when the call to kzalloc()
fails.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=188901
Signed-off-by: Pan Bian <bianpan2016@163.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Rafael J. Wysocki
Li, Fei
Anton Blanchard
Marcin Nowakowski
Vaidyanathan Srinivasan
Gautham R. Shenoy
Linus Torvalds
Ingo Molnar
Alex Shi
Pan Bian