linux.git/drivers/base, branch v4.14.30

dma-buf/fence: Fix lock inversion within dma-fence-array

2018-03-19T07:42:47+00:00

[ Upstream commit 03e4e0a9e02cf703da331ff6cfd57d0be9bf5692 ]

Ages ago Rob Clark noted,

"Currently with fence-array, we have a potential deadlock situation.  If
we fence_add_callback() on an array-fence, the array-fence's lock is
acquired first, and in it's ->enable_signaling() callback, it will install
cbs on it's array-member fences, so the array-member's lock is acquired
second.

But in the signal path, the array-member's lock is acquired first, and
the array-fence's lock acquired second."

Rob proposed either extensive changes to dma-fence to unnest the
fence-array signaling, or to defer the signaling onto a workqueue. This
is a more refined version of the later, that should keep the latency
of the fence signaling to a minimum by using an irq-work, which is
executed asap.

Reported-by: Rob Clark 
Suggested-by: Rob Clark 
References: 1476635975-21981-1-git-send-email-robdclark@gmail.com
Signed-off-by: Chris Wilson 
Cc: Rob Clark 
Cc: Gustavo Padovan 
Cc: Sumit Semwal 
Cc: Christian König 
Reviewed-by: Christian König 
Signed-off-by: Sumit Semwal 
Link: https://patchwork.freedesktop.org/patch/msgid/20171114162719.30958-1-chris@chris-wilson.co.uk
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

PM / runtime: Fix handling of suppliers with disabled runtime PM

2018-02-25T10:07:58+00:00

[ Upstream commit 31eb7431805493e10f4731f366cf4d4e3e952035 ]

Prevent rpm_get_suppliers() from returning an error code if runtime
PM is disabled for one or more of the supplier devices it wants to
runtime-resume, so as to make runtime PM work for devices with links
to suppliers that don't use runtime PM (such links may be created
during device enumeration even before it is known whether or not
runtime PM will be enabled for the devices in question, for example).

Fixes: 21d5c57b3726 (PM / runtime: Use device links)
Reported-by: Adrian Hunter 
Signed-off-by: Rafael J. Wysocki 
Reviewed-by: Lukas Wunner 
Tested-by: Adrian Hunter 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

PM / runtime: Update links_count also if !CONFIG_SRCU

2018-02-22T14:42:20+00:00

commit 433986c2c265d106d6a8e88006e0131fefc92b7b upstream.

Commit baa8809f6097 (PM / runtime: Optimize the use of device links)
added an invocation of pm_runtime_drop_link() to __device_link_del().
However there are two variants of that function, one for CONFIG_SRCU and
another for !CONFIG_SRCU, and the commit only modified the former.

Fixes: baa8809f6097 (PM / runtime: Optimize the use of device links)
Cc: v4.10+  # v4.10+
Signed-off-by: Lukas Wunner 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

sysfs/cpu: Add vulnerability folder

2018-01-17T08:45:27+00:00

commit 87590ce6e373d1a5401f6539f0c59ef92dd924a9 upstream.

As the meltdown/spectre problem affects several CPU architectures, it makes
sense to have common way to express whether a system is affected by a
particular vulnerability or not. If affected the way to express the
mitigation should be common as well.

Create /sys/devices/system/cpu/vulnerabilities folder and files for
meltdown, spectre_v1 and spectre_v2.

Allow architectures to override the show function.

Signed-off-by: Thomas Gleixner 
Reviewed-by: Greg Kroah-Hartman 
Reviewed-by: Konrad Rzeszutek Wilk 
Cc: Peter Zijlstra 
Cc: Will Deacon 
Cc: Dave Hansen 
Cc: Linus Torvalds 
Cc: Borislav Petkov 
Cc: David Woodhouse 
Link: https://lkml.kernel.org/r/20180107214913.096657732@linutronix.de
Signed-off-by: Greg Kroah-Hartman

drivers: base: cacheinfo: fix cache type for non-architected system cache

2018-01-02T19:31:16+00:00

commit f57ab9a01a36ef3454333251cc57e3a9948b17bf upstream.

Commit dfea747d2aba ("drivers: base: cacheinfo: support DT overrides for
cache properties") doesn't initialise the cache type if it's present
only in DT and the architecture is not aware of it. They are unified
system level cache which are generally transparent.

This patch check if the cache type is set to NOCACHE but the DT node
indicates that it's unified cache and sets the cache type accordingly.

Fixes: dfea747d2aba ("drivers: base: cacheinfo: support DT overrides for cache properties")
Reported-and-tested-by: Tan Xiaojun 
Cc: Greg Kroah-Hartman 
Signed-off-by: Sudeep Holla 
Signed-off-by: Greg Kroah-Hartman

PM / OPP: Move error message to debug level

2017-12-25T13:26:26+00:00

[ Upstream commit 035ed07208dc501d023873447113f3f178592156 ]

On some i.MX6 platforms which do not have speed grading
check, opp table will not be created in platform code,
so cpufreq driver prints the following error message:

cpu cpu0: dev_pm_opp_get_opp_count: OPP table not found (-19)

However, this is not really an error in this case because the
imx6q-cpufreq driver first calls dev_pm_opp_get_opp_count()
and if it fails, it means that platform code does not provide
OPP and then dev_pm_opp_of_add_table() will be called.

In order to avoid such confusing error message, move it to
debug level.

It is up to the caller of dev_pm_opp_get_opp_count() to check its
return value and decide if it will print an error or not.

Signed-off-by: Fabio Estevam 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

isa: Prevent NULL dereference in isa_bus driver callbacks

2017-12-14T08:52:51+00:00

commit 5a244727f428a06634f22bb890e78024ab0c89f3 upstream.

The isa_driver structure for an isa_bus device is stored in the device
platform_data member of the respective device structure. This
platform_data member may be reset to NULL if isa_driver match callback
for the device fails, indicating a device unsupported by the ISA driver.

This patch fixes a possible NULL pointer dereference if one of the
isa_driver callbacks to attempted for an unsupported device. This error
should not occur in practice since ISA devices are typically manually
configured and loaded by the users, but we may as well prevent this
error from popping up for the 0day testers.

Fixes: a5117ba7da37 ("[PATCH] Driver model: add ISA bus")
Signed-off-by: William Breathitt Gray 
Acked-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

firmware: cleanup FIRMWARE_IN_KERNEL message

2017-12-14T08:52:50+00:00

commit 0946b2fb38fdb6585a5ac3ca84ac73924f645952 upstream.

The help for FIRMWARE_IN_KERNEL still references the firmware_install
command that was recently removed by commit 5620a0d1aacd ("firmware:
delete in-kernel firmware").

Clean up the message to direct the user to their distribution's
linux-firmware package, and remove any reference to firmware being
included in the kernel source tree.

Fixes: 5620a0d1aacd ("firmware: delete in-kernel firmware").
Cc: Masahiro Yamada 
Cc: David Woodhouse 
Signed-off-by: Robin H. Johnson 
Signed-off-by: Greg Kroah-Hartman

PM / Domains: Fix genpd to deal with drivers returning 1 from ->prepare()

2017-12-10T12:40:38+00:00

[ Upstream commit 5241ab40f6e742f8a1631f8826faf6dc6412b3b5 ]

During system-wide PM, genpd relies on its PM callbacks to be invoked for
all its attached devices, as to deal with powering off/on the PM domain. In
other words, genpd is not compatible with the direct_complete path, if
executed by the PM core for any of its attached devices.

However, when genpd's ->prepare() callback invokes pm_generic_prepare(), it
does not take into account that it may return 1. Instead it treats that as
an error internally and expects the PM core to abort the prepare phase and
roll back. This leads to genpd not properly powering on/off the PM domain,
because its internal counters gets wrongly balanced.

To fix the behaviour, allow drivers to return 1 from their ->prepare()
callbacks, but let's return 0 from genpd's ->prepare() callback in such
case, as that prevents the PM core from running the direct_complete path
for the device.

Signed-off-by: Ulf Hansson 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

PM / OPP: Add missing of_node_put(np)

2017-11-30T08:40:41+00:00

commit 7978db344719dab1e56d05e6fc04aaaddcde0a5e upstream.

The for_each_available_child_of_node() loop in _of_add_opp_table_v2()
doesn't drop the reference to "np" on errors. Fix that.

Fixes: 274659029c9d (PM / OPP: Add support to parse "operating-points-v2" bindings)
Signed-off-by: Tobias Jordan 
[ VK: Improved commit log. ]
Signed-off-by: Viresh Kumar 
Reviewed-by: Stephen Boyd 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman