linux-stable/drivers/cpufreq
Sudeep Holla c6f27cdd4f cpufreq: check if policy is inactive early in __cpufreq_get()
[ Upstream commit 2f66196208 ]

cpuinfo_cur_freq gets current CPU frequency as detected by hardware
while scaling_cur_freq last known CPU frequency. Some platforms may not
allow checking the CPU frequency of an offline CPU or the associated
resources may have been released via cpufreq_exit when the CPU gets
offlined, in which case the policy would have been invalidated already.
If we attempt to get current frequency from the hardware, it may result
in hang or crash.

For example on Juno, I see:

Unable to handle kernel NULL pointer dereference at virtual address 0000000000000188
[0000000000000188] pgd=0000000000000000
Internal error: Oops: 96000004 [#1] PREEMPT SMP
Modules linked in:
CPU: 5 PID: 4202 Comm: cat Not tainted 4.20.0-08251-ga0f2c0318a15-dirty #87
Hardware name: ARM LTD ARM Juno Development Platform/ARM Juno Development Platform
pstate: 40000005 (nZcv daif -PAN -UAO)
pc : scmi_cpufreq_get_rate+0x34/0xb0
lr : scmi_cpufreq_get_rate+0x34/0xb0
Call trace:
 scmi_cpufreq_get_rate+0x34/0xb0
 __cpufreq_get+0x34/0xc0
 show_cpuinfo_cur_freq+0x24/0x78
 show+0x40/0x60
 sysfs_kf_seq_show+0xc0/0x148
 kernfs_seq_show+0x44/0x50
 seq_read+0xd4/0x480
 kernfs_fop_read+0x15c/0x208
 __vfs_read+0x60/0x188
 vfs_read+0x94/0x150
 ksys_read+0x6c/0xd8
 __arm64_sys_read+0x24/0x30
 el0_svc_common+0x78/0x100
 el0_svc_handler+0x38/0x78
 el0_svc+0x8/0xc
---[ end trace 3d1024e58f77f6b2 ]---

So fix the issue by checking if the policy is invalid early in
__cpufreq_get before attempting to get the current frequency.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-20 10:25:40 +01:00
..
acpi-cpufreq.c Additional power management updates for 4.18-rc1 2018-06-13 07:24:18 -07:00
amd_freq_sensitivity.c cpufreq: AMD: Ignore the check for ProcFeedback in ST/CZ 2018-02-07 11:26:37 +01:00
arm_big_little.c treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
arm_big_little.h cpufreq: arm_big_little: make function arguments and structure pointer const 2017-11-08 23:22:19 +01:00
arm_big_little_dt.c cpufreq: arm_big_little: make cpufreq_arm_bL_ops structures const 2017-11-08 23:22:20 +01:00
armada-37xx-cpufreq.c cpufreq: armada-37xx: Add AVS support 2018-07-18 10:10:25 +02:00
bmips-cpufreq.c treewide: kmalloc() -> kmalloc_array() 2018-06-12 16:19:22 -07:00
brcmstb-avs-cpufreq.c treewide: devm_kzalloc() -> devm_kcalloc() 2018-06-12 16:19:22 -07:00
cppc_cpufreq.c cpufreq / CPPC: Add cpuinfo_cur_freq support for CPPC 2018-07-18 10:13:16 +02:00
cpufreq-dt-platdev.c cpufreq: Add Kryo CPU scaling driver 2018-05-30 12:53:11 +02:00
cpufreq-dt.c cpufreq: dt: Try freeing static OPPs only if we have added them 2018-11-13 11:08:24 -08:00
cpufreq-dt.h cpufreq: dt: Allow platform specific suspend/resume callbacks 2018-05-10 11:43:59 +02:00
cpufreq-nforce2.c cpufreq: Add CPUFREQ_NO_AUTO_DYNAMIC_SWITCHING cpufreq driver flag 2017-07-26 00:15:46 +02:00
cpufreq.c cpufreq: check if policy is inactive early in __cpufreq_get() 2019-02-20 10:25:40 +01:00
cpufreq_conservative.c cpufreq: conservative: Take limits changes into account properly 2018-11-13 11:08:16 -08:00
cpufreq_governor.c cpufreq: governor: Avoid accessing invalid governor_data 2018-08-16 23:03:29 +02:00
cpufreq_governor.h cpufreq: Replace "max_transition_latency" with "dynamic_switching" 2017-07-26 00:15:45 +02:00
cpufreq_governor_attr_set.c cpufreq: governor: Move abstract gov_attr_set code to seperate file 2016-04-02 01:09:01 +02:00
cpufreq_ondemand.c cpufreq: governor: Drop min_sampling_rate 2017-07-22 02:25:20 +02:00
cpufreq_ondemand.h cpufreq: ondemand: Don't keep a copy of freq_table pointer 2016-06-09 00:58:06 +02:00
cpufreq_performance.c cpufreq: governor: Get rid of governor events 2016-06-02 23:24:15 +02:00
cpufreq_powersave.c cpufreq: governor: Get rid of governor events 2016-06-02 23:24:15 +02:00
cpufreq_stats.c cpufreq: stats: Change return type of cpufreq_stats_update() as void 2018-01-05 13:22:46 +01:00
cpufreq_userspace.c cpufreq: governor: Get rid of governor events 2016-06-02 23:24:15 +02:00
davinci-cpufreq.c ARM: davinci: da850: fix da850_set_pll0rate() 2017-01-02 15:02:51 +05:30
e_powersaver.c cpufreq: e_powersaver: Don't validate the frequency table twice 2018-03-20 12:07:52 +01:00
elanfreq.c cpufreq: elanfreq: Don't validate the frequency table twice 2018-03-20 12:07:52 +01:00
freq_table.c cpufreq: Drop cpufreq_table_validate_and_show() 2018-04-10 08:40:45 +02:00
gx-suspmod.c cpufreq: Add CPUFREQ_NO_AUTO_DYNAMIC_SWITCHING cpufreq driver flag 2017-07-26 00:15:46 +02:00
highbank-cpufreq.c
ia64-acpi-cpufreq.c treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
imx6q-cpufreq.c cpufreq: imx6q: add return value check for voltage scale 2018-12-01 09:37:32 +01:00
intel_pstate.c cpufreq: intel_pstate: Ignore turbo active ratio in HWP 2018-08-06 10:22:27 +02:00
Kconfig cpufreq: remove at32ap-cpufreq 2018-02-07 11:44:23 +01:00
Kconfig.arm cpufreq: exynos: Remove support for Exynos5440 2018-07-17 19:55:51 +02:00
Kconfig.powerpc
Kconfig.x86 sched/x86: Change CONFIG_SCHED_ITMT to CONFIG_SCHED_MC_PRIO 2016-11-30 08:27:08 +01:00
kirkwood-cpufreq.c cpufreq: kirkwood-cpufreq:- Handle return value of clk_prepare_enable() 2017-05-30 00:09:41 +02:00
longhaul.c treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
longhaul.h
longrun.c cpufreq: Don't set transition_latency for setpolicy drivers 2017-07-26 00:15:43 +02:00
loongson1-cpufreq.c CPUFREQ: Loongson1: Replace goto out with return in ls1x_cpufreq_probe() 2016-05-13 14:02:08 +02:00
loongson2_cpufreq.c cpufreq: Loongson2: constify platform_device_id 2017-08-18 01:44:21 +02:00
Makefile cpufreq: exynos: Remove support for Exynos5440 2018-07-17 19:55:51 +02:00
maple-cpufreq.c cpufreq: Use consistent prefixing via pr_fmt 2016-04-09 01:35:18 +02:00
mediatek-cpufreq.c cpufreq: mediatek: Don't validate the frequency table twice 2018-03-20 12:07:52 +01:00
mvebu-cpufreq.c cpufreq: mvebu: Free opp if registering failed 2017-12-16 02:29:43 +01:00
omap-cpufreq.c PM / OPP: Update OPP users to put reference 2017-01-30 09:22:21 +01:00
p4-clockmod.c cpufreq: p4-clockmod: Don't validate the frequency table twice 2018-03-20 12:07:52 +01:00
pasemi-cpufreq.c cpufreq: Add and use cpufreq_for_each_{valid_,}entry_idx() 2018-02-08 10:21:39 +01:00
pcc-cpufreq.c Merge back cpufreq material for 4.19. 2018-07-25 13:28:01 +02:00
pmac32-cpufreq.c cpufreq: Add CPUFREQ_NO_AUTO_DYNAMIC_SWITCHING cpufreq driver flag 2017-07-26 00:15:46 +02:00
pmac64-cpufreq.c cpufreq: Convert to using %pOF instead of full_name 2017-08-25 01:20:46 +02:00
powernow-k6.c cpufreq: powernow: Don't validate the frequency table twice 2018-03-20 12:07:52 +01:00
powernow-k7.c cpufreq: powernow: Don't validate the frequency table twice 2018-03-20 12:07:52 +01:00
powernow-k7.h
powernow-k8.c cpufreq: powernow: Don't validate the frequency table twice 2018-03-20 12:07:52 +01:00
powernow-k8.h
powernv-cpufreq.c cpufreq: powernv: Remove global pstate ramp-down timer in POWER9 2018-07-09 18:06:02 +10:00
ppc_cbe_cpufreq.c cpufreq: ppc_cbe: Don't validate the frequency table twice 2018-03-20 12:07:52 +01:00
ppc_cbe_cpufreq.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ppc_cbe_cpufreq_pervasive.c
ppc_cbe_cpufreq_pmi.c cpufreq: Remove CPUFREQ_START notifier event 2017-02-04 00:05:30 +01:00
pxa2xx-cpufreq.c cpufreq: pxa: Don't validate the frequency table twice 2018-03-20 12:07:52 +01:00
pxa3xx-cpufreq.c treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
qcom-cpufreq-kryo.c cpufreq: qcom-kryo: Fix section annotations 2018-09-29 15:01:10 +02:00
qoriq-cpufreq.c cpufreq: qoirq: Don't validate the frequency table twice 2018-03-20 12:07:52 +01:00
s3c24xx-cpufreq-debugfs.c cpufreq: Use consistent prefixing via pr_fmt 2016-04-09 01:35:18 +02:00
s3c24xx-cpufreq.c treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
s3c64xx-cpufreq.c cpufreq: s3c64xx: remove incorrect __init annotation 2016-12-21 02:54:18 +01:00
s3c2410-cpufreq.c
s3c2412-cpufreq.c cpufreq: Use consistent prefixing via pr_fmt 2016-04-09 01:35:18 +02:00
s3c2416-cpufreq.c cpufreq: s3c2416: double free on driver init error path 2017-02-09 01:22:45 +01:00
s3c2440-cpufreq.c cpufreq: s3c2440: fix spelling mistake: "divsiors" -> "divisors" 2018-05-10 11:50:42 +02:00
s5pv210-cpufreq.c cpufreq: s5pv210: add missing of_node_put() 2017-07-26 22:54:01 +02:00
sa1100-cpufreq.c cpufreq: Add CPUFREQ_NO_AUTO_DYNAMIC_SWITCHING cpufreq driver flag 2017-07-26 00:15:46 +02:00
sa1110-cpufreq.c cpufreq: Add CPUFREQ_NO_AUTO_DYNAMIC_SWITCHING cpufreq driver flag 2017-07-26 00:15:46 +02:00
sc520_freq.c cpufreq: sc520: Don't validate the frequency table twice 2018-03-20 12:07:52 +01:00
scmi-cpufreq.c cpufreq: scmi: Fix frequency invariance in slow path 2019-01-16 22:04:29 +01:00
scpi-cpufreq.c cpufreq: scpi: Don't validate the frequency table twice 2018-03-20 12:07:52 +01:00
sfi-cpufreq.c treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
sh-cpufreq.c cpufreq: sh: Don't validate the frequency table twice 2018-03-20 12:07:52 +01:00
sparc-us2e-cpufreq.c cpufreq: sparc: Don't validate the frequency table twice 2018-03-20 12:07:52 +01:00
sparc-us3-cpufreq.c cpufreq: sparc: Don't validate the frequency table twice 2018-03-20 12:07:52 +01:00
spear-cpufreq.c treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
speedstep-centrino.c cpufreq: speedstep: Don't validate the frequency table twice 2018-03-20 12:07:52 +01:00
speedstep-ich.c cpufreq: speedstep: Don't validate the frequency table twice 2018-03-20 12:07:52 +01:00
speedstep-lib.c cpufreq: speedstep: fix speedstep_detect_processor()'s return type 2018-05-10 11:46:00 +02:00
speedstep-lib.h
speedstep-smi.c cpufreq: speedstep: Don't validate the frequency table twice 2018-03-20 12:07:52 +01:00
sti-cpufreq.c cpufreq: Convert to using %pOF instead of full_name 2017-08-25 01:20:46 +02:00
tango-cpufreq.c cpufreq: dt: Don't use generic platdev driver for tango 2017-07-22 02:20:59 +02:00
tegra20-cpufreq.c cpufreq: tegra20: Wrap cpufreq into platform driver 2018-05-21 13:44:24 +02:00
tegra124-cpufreq.c cpufreq: tegra124: No need of setting platform-data 2016-04-09 01:12:09 +02:00
tegra186-cpufreq.c cpufreq: tegra186: Don't validate the frequency table twice 2018-03-20 12:07:53 +01:00
ti-cpufreq.c cpufreq: ti-cpufreq: Only register platform_device when supported 2018-12-13 09:16:13 +01:00
unicore2-cpufreq.c cpufreq: Add CPUFREQ_NO_AUTO_DYNAMIC_SWITCHING cpufreq driver flag 2017-07-26 00:15:46 +02:00
vexpress-spc-cpufreq.c cpufreq: arm_big_little: make cpufreq_arm_bL_ops structures const 2017-11-08 23:22:20 +01:00