Several snapshot ioctls were marked for removal quite some time ago,
since they were deprecated. Remove them.
Suggested-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
PM / Sleep: Fix freezer failures due to racy usermodehelper_is_disabled()
Commit a144c6a (PM: Print a warning if firmware is requested when tasks
are frozen) introduced usermodehelper_is_disabled() to warn and exit
immediately if firmware is requested when usermodehelpers are disabled.
However, it is racy. Consider the following scenario, currently used in
drivers/base/firmware_class.c:
...
if (usermodehelper_is_disabled())
goto out;
/* Do actual work */
...
out:
return err;
Nothing prevents someone from disabling usermodehelpers just after the check
in the 'if' condition, which means that it is quite possible to try doing the
"actual work" with usermodehelpers disabled, leading to undesirable
consequences.
In particular, this race condition in _request_firmware() causes task freezing
failures whenever suspend/hibernation is in progress because, it wrongly waits
to get the firmware/microcode image from userspace when actually the
usermodehelpers are disabled or userspace has been frozen.
Some of the example scenarios that cause freezing failures due to this race
are those that depend on userspace via request_firmware(), such as x86
microcode module initialization and microcode image reload.
Previous discussions about this issue can be found at:
http://thread.gmane.org/gmane.linux.kernel/1198291/focus=1200591
This patch adds proper synchronization to fix this issue.
It is to be noted that this patchset fixes the freezing failures but doesn't
remove the warnings. IOW, it does not attempt to add explicit synchronization
to x86 microcode driver to avoid requesting microcode image at inopportune
moments. Because, the warnings were introduced to highlight such cases, in the
first place. And we need not silence the warnings, since we take care of the
*real* problem (freezing failure) and hence, after that, the warnings are
pretty harmless anyway.
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Mark Brown [Thu, 8 Dec 2011 22:27:48 +0000 (23:27 +0100)]
ARM: S3C64XX: Implement basic power domain support
The S3C64xx SoCs contain a set of gateable power domains which can be
enabled and disabled at runtime in order to save power. Use the generic
power domain code to implement support for these in software, enabling
runtime control of most domains:
- ETM (not supported in mainline).
- Domain G: 3D acceleration (no mainline support).
- Domain V: MFC (no mainline support).
- Domain I: JPEG and camera interface (no mainline support).
- Domain P: 2D acceleration, TV encoder and scaler (no mainline support)
- Domain S: Security (no mainline support).
- Domain F: LCD (driver already uses runtime PM), post processing and
rotation (no mainline support).
The IROM domain is marked as always enabled as we should arrange for it
to be enabled when we suspend which will need a bit more work.
Due to all the conditional device registration that the platform does
wrap s3c_pm_init() with s3c64xx_pm_init() which actually puts the device
into the power domain after the machines have registered, looking for
platform data to tell if the device was registered. Since currently only
Cragganmore actually sets up PM that is the only machine updated.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Kukjin Kim <kgene.kim@samsung.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Mark Brown [Thu, 8 Dec 2011 22:27:40 +0000 (23:27 +0100)]
PM / shmobile: Use common always on power domain governor
Saves a tiny amount of code.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Magnus Damm <damm@opensource.se> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Mark Brown [Thu, 8 Dec 2011 22:27:28 +0000 (23:27 +0100)]
PM / Domains: Provide an always on power domain governor
Since systems are likely to have power domains that can't be turned off
for various reasons at least temporarily while implementing power domain
support provide a default governor which will always refuse to power off
the domain, saving platforms having to implement their own.
Since the code is so tiny don't bother with a Kconfig symbol for it.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* pm-domains:
PM / Domains: Fix default system suspend/resume operations
PM / Domains: Make it possible to assign names to generic PM domains
PM / Domains: fix compilation failure for CONFIG_PM_GENERIC_DOMAINS unset
PM / Domains: Automatically update overoptimistic latency information
PM / Domains: Add default power off governor function (v4)
PM / Domains: Add device stop governor function (v4)
PM / Domains: Rework system suspend callback routines (v2)
PM / Domains: Introduce "save/restore state" device callbacks
PM / Domains: Make it possible to use per-device domain callbacks
* pm-misc:
CPU: Add right qualifiers for alloc_frozen_cpus() and cpu_hotplug_pm_sync_init()
PM / Usermodehelper: Cleanup remnants of usermodehelper_pm_callback()
PM / Sleep: Recommend [un]lock_system_sleep() over using pm_mutex directly
Update the documentation to explain the perils of directly using
mutex_[un]lock(&pm_mutex) and recommend the usage of the safe
APIs [un]lock_system_sleep() instead.
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
PM / Sleep: Replace mutex_[un]lock(&pm_mutex) with [un]lock_system_sleep()
Using [un]lock_system_sleep() is safer than directly using mutex_[un]lock()
on 'pm_mutex', since the latter could lead to freezing failures. Hence convert
all the present users of mutex_[un]lock(&pm_mutex) to use these safe APIs
instead.
Suggested-by: Tejun Heo <tj@kernel.org> Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Reviewed-by: Simon Horman <horms@verge.net.au> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
projects / karo-tx-linux.git / log