linux-stable.git/drivers/cpufreq, branch v4.4.7

cpufreq: Fix NULL reference crash while accessing policy->governor_data

2016-03-03T23:07:25+00:00

commit e4b133cc4b30b48d488e4e4fffb132f173ce4358 upstream.

There is a race discovered by Juri, where we are able to:
- create and read a sysfs file before policy->governor_data is being set
  to a non NULL value.
  OR
- set policy->governor_data to NULL, and reading a file before being
  destroyed.

And so such a crash is reported:

Unable to handle kernel NULL pointer dereference at virtual address 0000000c
pgd = edfc8000
[0000000c] *pgd=bfc8c835
Internal error: Oops: 17 [#1] SMP ARM
Modules linked in:
CPU: 4 PID: 1730 Comm: cat Not tainted 4.5.0-rc1+ #463
Hardware name: ARM-Versatile Express
task: ee8e8480 ti: ee930000 task.ti: ee930000
PC is at show_ignore_nice_load_gov_pol+0x24/0x34
LR is at show+0x4c/0x60
pc : []    lr : []    psr: a0070013
sp : ee931dd0  ip : ee931de0  fp : ee931ddc
r10: ee4bc290  r9 : 00001000  r8 : ef2cb000
r7 : ee4bc200  r6 : ef2cb000  r5 : c0af57b0  r4 : ee4bc2e0
r3 : 00000000  r2 : 00000000  r1 : c0928df4  r0 : ef2cb000
Flags: NzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
Control: 10c5387d  Table: adfc806a  DAC: 00000051
Process cat (pid: 1730, stack limit = 0xee930210)
Stack: (0xee931dd0 to 0xee932000)
1dc0:                                     ee931dfc ee931de0 c058ae88 c058f1a4
1de0: edce3bc0 c07bfca4 edce3ac0 00001000 ee931e24 ee931e00 c01fcb90 c058ae48
1e00: 00000001 edce3bc0 00000000 00000001 ee931e50 ee8ff480 ee931e34 ee931e28
1e20: c01fb33c c01fcb0c ee931e8c ee931e38 c01a5210 c01fb314 ee931e9c ee931e48
1e40: 00000000 edce3bf0 befe4a00 ee931f78 00000000 00000000 000001e4 00000000
1e60: c00545a8 edce3ac0 00001000 00001000 befe4a00 ee931f78 00000000 00001000
1e80: ee931ed4 ee931e90 c01fbed8 c01a5038 ed085a58 00020000 00000000 00000000
1ea0: c0ad72e4 ee931f78 ee8ff488 ee8ff480 c077f3fc 00001000 befe4a00 ee931f78
1ec0: 00000000 00001000 ee931f44 ee931ed8 c017c328 c01fbdc4 00001000 00000000
1ee0: ee8ff480 00001000 ee931f44 ee931ef8 c017c65c c03deb10 ee931fac ee931f08
1f00: c0009270 c001f290 c0a8d968 ef2cb000 ef2cb000 ee8ff480 00000020 ee8ff480
1f20: ee8ff480 befe4a00 00001000 ee931f78 00000000 00000000 ee931f74 ee931f48
1f40: c017d1ec c017c2f8 c019c724 c019c684 ee8ff480 ee8ff480 00001000 befe4a00
1f60: 00000000 00000000 ee931fa4 ee931f78 c017d2a8 c017d160 00000000 00000000
1f80: 000a9f20 00001000 befe4a00 00000003 c000ffe4 ee930000 00000000 ee931fa8
1fa0: c000fe40 c017d264 000a9f20 00001000 00000003 befe4a00 00001000 00000000
Unable to handle kernel NULL pointer dereference at virtual address 0000000c
1fc0: 000a9f20 00001000 befe4a00 00000003 00000000 00000000 00000003 00000001
pgd = edfc4000
[0000000c] *pgd=bfcac835
1fe0: 00000000 befe49dc 000197f8 b6e35dfc 60070010 00000003 3065b49d 134ac2c9

[] (show_ignore_nice_load_gov_pol) from [] (show+0x4c/0x60)
[] (show) from [] (sysfs_kf_seq_show+0x90/0xfc)
[] (sysfs_kf_seq_show) from [] (kernfs_seq_show+0x34/0x38)
[] (kernfs_seq_show) from [] (seq_read+0x1e4/0x4e4)
[] (seq_read) from [] (kernfs_fop_read+0x120/0x1a0)
[] (kernfs_fop_read) from [] (__vfs_read+0x3c/0xe0)
[] (__vfs_read) from [] (vfs_read+0x98/0x104)
[] (vfs_read) from [] (SyS_read+0x50/0x90)
[] (SyS_read) from [] (ret_fast_syscall+0x0/0x1c)
Code: e5903044 e1a00001 e3081df4 e34c1092 (e593300c)
---[ end trace 5994b9a5111f35ee ]---

Fix that by making sure, policy->governor_data is updated at the right
places only.

Reported-and-tested-by: Juri Lelli 
Signed-off-by: Viresh Kumar 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

cpufreq: pxa2xx: fix pxa_cpufreq_change_voltage prototype

2016-03-03T23:07:25+00:00

commit fb2a24a1c6457d21df9fae0dd66b20c63ba56077 upstream.

There are two definitions of pxa_cpufreq_change_voltage, with slightly
different prototypes after one of them had its argument marked 'const'.
Now the other one (for !CONFIG_REGULATOR) produces a harmless warning:

drivers/cpufreq/pxa2xx-cpufreq.c: In function 'pxa_set_target':
drivers/cpufreq/pxa2xx-cpufreq.c:291:36: warning: passing argument 1 of 'pxa_cpufreq_change_voltage' discards 'const' qualifier from pointer target type [-Wdiscarded-qualifiers]
   ret = pxa_cpufreq_change_voltage(&pxa_freq_settings[idx]);
                                    ^
drivers/cpufreq/pxa2xx-cpufreq.c:205:12: note: expected 'struct pxa_freqs *' but argument is of type 'const struct pxa_freqs *'
 static int pxa_cpufreq_change_voltage(struct pxa_freqs *pxa_freq)
            ^

This changes the prototype in the same way as the other, which
avoids the warning.

Fixes: 03c229906311 (cpufreq: pxa: make pxa_freqs arrays const)
Signed-off-by: Arnd Bergmann 
Acked-by: Viresh Kumar 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

cpufreq: scpi-cpufreq: signedness bug in scpi_get_dvfs_info()

2015-12-24T01:11:37+00:00

The "domain" variable needs to be signed for the error handling to work.

Fixes: 8def31034d03 (cpufreq: arm_big_little: add SCPI interface driver)
Signed-off-by: Dan Carpenter 
Acked-by: Viresh Kumar 
Acked-by: Sudeep Holla 
Signed-off-by: Rafael J. Wysocki

Merge branches 'powercap', 'pm-cpufreq' and 'pm-domains'

2015-12-14T21:58:57+00:00

* powercap:
  powercap / RAPL: fix BIOS lock check

* pm-cpufreq:
  cpufreq: intel_pstate: Minor cleanup for FRAC_BITS
  cpufreq: tegra: add regulator dependency for T124

* pm-domains:
  PM / Domains: Allow runtime PM callbacks to be re-used during system PM

Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

2015-12-13T00:43:44+00:00

Pull ARM SoC fixes from Arnd Bergmann:
 "Here are a bunch of small bug fixes for various ARM platforms, nothing
  really sticks out this week, most of either fixes bugs in code that
  was just added in 4.4, or that has been broken for many years without
  anyone noticing.

  at91/sama5d2:
   - fix sama5de hardware setup of sd/mmc interface
   - proper selection of pinctrl drivers.  PIO4 is necessary for sama5d2

  berlin:
   - fix incorrect clock input for SDIO

  exynos:
   - Fix potential NULL pointer dereference in Exynos PMU driver.

  imx:
   - Fix vf610 SAI clock configuration bug which is discovered by the
     newly added master mode support in SAI audio driver.
   - Fix buggy L2 cache latency values in vf610 device trees, which may
     cause system hang when cpu runs at a higher frequency.

  ixp4xx:
   - fix prototypes for readl/writel functions

  ls2080a:
   - use little-endian register access for GPIO and SDHCI

  omap:
   - Fix clock source for ARM TWD and global timers on am437x
   - Always select REGULATOR_FIXED_VOLTAGE for omap2+ instead of when
     MACH_OMAP3_PANDORA is selected
   - Fix SPI DMA handles for dm816x as only some were mapped
   - Fix up mbox cells for dm816x to make mailbox usable

  pxa:
   - use PWM lookup table for all ezx machines

  s3c24xx:
   - Remove incorrect __init annotation from s3c24xx cpufreq driver
     structures.

  versatile:
   - fix PCI IRQ mapping on Versatile PB"

* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  ls2080a/dts: Add little endian property for GPIO IP block
  dt-bindings: define little-endian property for QorIQ GPIO
  ARM64: dts: ls2080a: fix eSDHC endianness
  ARM: dts: vf610: use reset values for L2 cache latencies
  ARM: pxa: use PWM lookup table for all machines
  ARM: dts: berlin: add 2nd clock for BG2Q sdhci0 and sdhci1
  ARM: dts: berlin: correct BG2Q's sdhci2 2nd clock
  ARM: dts: am4372: fix clock source for arm twd and global timers
  ARM: at91: fix pinctrl driver selection
  ARM: at91/dt: add always-on to 1.8V regulator
  ARM: dts: vf610: fix clock definition for SAI2
  ARM: imx: clk-vf610: fix SAI clock tree
  ARM: ixp4xx: fix read{b,w,l} return types
  irqchip/versatile-fpga: Fix PCI IRQ mapping on Versatile PB
  ARM: OMAP2+: enable REGULATOR_FIXED_VOLTAGE
  ARM: dts: add dm816x missing spi DT dma handles
  ARM: dts: add dm816x missing #mbox-cells
  cpufreq: s3c24xx: Do not mark s3c2410_plls_add as __init
  ARM: EXYNOS: Fix potential NULL pointer access in exynos_sys_powerdown_conf

cpufreq: intel_pstate: Minor cleanup for FRAC_BITS

2015-12-12T01:28:19+00:00

785ee27 ("cpufreq: intel_pstate: Fix limits->max_perf rounding error")
hardcodes the value of FRAC_BITS.  This patch fixes that minor issue.

Fixes: 785ee2788141 (cpufreq: intel_pstate: Fix limits->max_perf rounding error)
Signed-off-by: Prarit Bhargava 
Acked-by: Viresh Kumar 
Signed-off-by: Rafael J. Wysocki

cpufreq: tegra: add regulator dependency for T124

2015-12-12T01:25:56+00:00

This driver is the only one that calls regulator_sync_voltage(), but it
can currently be built with CONFIG_REGULATOR disabled, producing
this build error:

drivers/cpufreq/tegra124-cpufreq.c: In function 'tegra124_cpu_switch_to_pllx':
drivers/cpufreq/tegra124-cpufreq.c:68:2: error: implicit declaration of function 'regulator_sync_voltage' [-Werror=implicit-function-declaration]
  regulator_sync_voltage(priv->vdd_cpu_reg);

My first attempt was to implement a helper for this function
for regulator_sync_voltage, but Mark Brown explained:

   We don't do this for *all* regulator API functions - there's some where
   using them strongly suggests that there is actually a dependency on
   the regulator API.  This does seem like it might be falling into the
   specialist category [...]
   Looking at the code I'm pretty unclear on what the authors think the
   use of _sync_voltage() is doing in the first place so it may be even
   better to just remove the call.  It seems to have been included in the
   first commit so there's not changelog explaining things and there's
   no comment either.  I'd *expect* it to be a noop as far as I can see.

This adds the dependency to make the driver always build successfully
or not be enabled at all. Alternatively, we could investigate if the
driver should stop calling regulator_sync_voltage instead.

Signed-off-by: Arnd Bergmann 
Acked-by: Viresh Kumar 
Acked-by: Jon Hunter 
Signed-off-by: Rafael J. Wysocki

Merge tag 'samsung-fixes-4.4' of https://git.kernel.org/pub/scm/linux/kernel/git/krzk/linux into fixes

2015-12-10T23:19:37+00:00

Merge "Fixes for Exynos" from Krzysztof Kozlowski:

1. Fix potential NULL pointer dereference in Exynos PMU driver.
2. Remove incorrect __init annotation from s3c24xx cpufreq driver
   structures.

* tag 'samsung-fixes-4.4' of https://git.kernel.org/pub/scm/linux/kernel/git/krzk/linux:
  cpufreq: s3c24xx: Do not mark s3c2410_plls_add as __init
  ARM: EXYNOS: Fix potential NULL pointer access in exynos_sys_powerdown_conf

Merge branches 'pm-domains' and 'pm-cpufreq'

2015-12-04T13:01:42+00:00

* pm-domains:
  PM / Domains: Fix bad of_node_put() in failure paths of genpd_dev_pm_attach()
  PM / Domains: Validate cases of a non-bound driver in genpd governor

* pm-cpufreq:
  cpufreq: use last policy after online for drivers with ->setpolicy

cpufreq: use last policy after online for drivers with ->setpolicy

2015-12-02T22:50:33+00:00

For cpufreq drivers which use setpolicy interface, after offline->online
the policy is set to default. This can be reproduced by setting the
default policy of intel_pstate or longrun to ondemand and then change to
"performance". After offline and online, the setpolicy will be called with
the policy=ondemand.

For drivers using governors this condition is handled by storing
last_governor, during offline and restoring during online. The same should
be done for drivers using setpolicy interface. Storing last_policy during
offline and restoring during online.

Signed-off-by: Srinivas Pandruvada 
Signed-off-by: Rafael J. Wysocki