Commit Graph

500 Commits

Author SHA1 Message Date
d6931bff1c PM: runtime: Redefine pm_runtime_release_supplier()
commit 07358194ba upstream.

Instead of passing an extra bool argument to pm_runtime_release_supplier(),
make its callers take care of triggering a runtime-suspend of the
supplier device as needed.

No expected functional impact.

Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: 5.1+ <stable@vger.kernel.org> # 5.1+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-12 16:32:18 +02:00
37b25de3af PM: runtime: Add safety net to supplier device release
[ Upstream commit d1579e6119 ]

Because refcount_dec_not_one() returns true if the target refcount
becomes saturated, it is generally unsafe to use its return value as
a loop termination condition, but that is what happens when a device
link's supplier device is released during runtime PM suspend
operations and on device link removal.

To address this, introduce pm_runtime_release_supplier() to be used
in the above cases which will check the supplier device's runtime
PM usage counter in addition to the refcount_dec_not_one() return
value, so the loop can be terminated in case the rpm_active refcount
value becomes invalid, and update the code in question to use it as
appropriate.

This change is not expected to have any visible functional impact.

Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-01-27 10:54:17 +01:00
e1959450b7 driver core: Fix possible memory leak in device_link_add()
[ Upstream commit df0a181494 ]

I got memory leak as follows:

unreferenced object 0xffff88801f0b2200 (size 64):
  comm "i2c-lis2hh12-21", pid 5455, jiffies 4294944606 (age 15.224s)
  hex dump (first 32 bytes):
    72 65 67 75 6c 61 74 6f 72 3a 72 65 67 75 6c 61  regulator:regula
    74 6f 72 2e 30 2d 2d 69 32 63 3a 31 2d 30 30 31  tor.0--i2c:1-001
  backtrace:
    [<00000000bf5b0c3b>] __kmalloc_track_caller+0x19f/0x3a0
    [<0000000050da42d9>] kvasprintf+0xb5/0x150
    [<000000004bbbed13>] kvasprintf_const+0x60/0x190
    [<00000000cdac7480>] kobject_set_name_vargs+0x56/0x150
    [<00000000bf83f8e8>] dev_set_name+0xc0/0x100
    [<00000000cc1cf7e3>] device_link_add+0x6b4/0x17c0
    [<000000009db9faed>] _regulator_get+0x297/0x680
    [<00000000845e7f2b>] _devm_regulator_get+0x5b/0xe0
    [<000000003958ee25>] st_sensors_power_enable+0x71/0x1b0 [st_sensors]
    [<000000005f450f52>] st_accel_i2c_probe+0xd9/0x150 [st_accel_i2c]
    [<00000000b5f2ab33>] i2c_device_probe+0x4d8/0xbe0
    [<0000000070fb977b>] really_probe+0x299/0xc30
    [<0000000088e226ce>] __driver_probe_device+0x357/0x500
    [<00000000c21dda32>] driver_probe_device+0x4e/0x140
    [<000000004e650441>] __device_attach_driver+0x257/0x340
    [<00000000cf1891b8>] bus_for_each_drv+0x166/0x1e0

When device_register() returns an error, the name allocated in dev_set_name()
will be leaked, the put_device() should be used instead of kfree() to give up
the device reference, then the name will be freed in kobject_cleanup() and the
references of consumer and supplier will be decreased in device_link_release_fn().

Fixes: 287905e68d ("driver core: Expose device link details in sysfs")
Reported-by: Hulk Robot <hulkci@huawei.com>
Reviewed-by: Saravana Kannan <saravanak@google.com>
Reviewed-by: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20210930085714.2057460-1-yangyingliang@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-11-18 14:04:16 +01:00
be8ef91d61 driver core: Reject pointless SYNC_STATE_ONLY device links
commit f729a592ad upstream.

SYNC_STATE_ONLY device links intentionally allow cycles because cyclic
sync_state() dependencies are valid and necessary.

However a SYNC_STATE_ONLY device link where the consumer and the supplier
are the same device is pointless because the device link would be deleted
as soon as the device probes (because it's also the consumer) and won't
affect when the sync_state() callback is called. It's a waste of CPU cycles
and memory to create this device link. So reject any attempts to create
such a device link.

Fixes: 05ef983e0d ("driver core: Add device link support for SYNC_STATE_ONLY flag")
Cc: stable <stable@vger.kernel.org>
Reported-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20210929190549.860541-1-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-20 11:45:01 +02:00
312730cd15 PCI/MSI: Protect msi_desc::masked for multi-MSI
commit 77e89afc25 upstream.

Multi-MSI uses a single MSI descriptor and there is a single mask register
when the device supports per vector masking. To avoid reading back the mask
register the value is cached in the MSI descriptor and updates are done by
clearing and setting bits in the cache and writing it to the device.

But nothing protects msi_desc::masked and the mask register from being
modified concurrently on two different CPUs for two different Linux
interrupts which belong to the same multi-MSI descriptor.

Add a lock to struct device and protect any operation on the mask and the
mask register with it.

This makes the update of msi_desc::masked unconditional, but there is no
place which requires a modification of the hardware register without
updating the masked cache.

msi_mask_irq() is now an empty wrapper which will be cleaned up in follow
up changes.

The problem goes way back to the initial support of multi-MSI, but picking
the commit which introduced the mask cache is a valid cut off point
(2.6.30).

Fixes: f2440d9acb ("PCI MSI: Refactor interrupt masking code")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210729222542.726833414@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-18 08:59:17 +02:00
2831eeb7bc driver core: Prevent warning when removing a device link from unregistered consumer
commit e64daad660 upstream.

sysfs_remove_link() causes a warning if the parent directory does not
exist. That can happen if the device link consumer has not been registered.
So do not attempt sysfs_remove_link() in that case.

Fixes: 287905e68d ("driver core: Expose device link details in sysfs")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: stable@vger.kernel.org # 5.9+
Reviewed-by: Rafael J. Wysocki <rafael@kernel.org>
Link: https://lore.kernel.org/r/20210716114408.17320-2-adrian.hunter@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-28 14:35:47 +02:00
d007150b4e drivers: base: Fix device link removal
commit 80dd33cf72 upstream.

When device_link_free() drops references to the supplier and
consumer devices of the device link going away and the reference
being dropped turns out to be the last one for any of those
device objects, its ->release callback will be invoked and it
may sleep which goes against the SRCU callback execution
requirements.

To address this issue, make the device link removal code carry out
the device_link_free() actions preceded by SRCU synchronization from
a separate work item (the "long" workqueue is used for that, because
it does not matter when the device link memory is released and it may
take time to get to that point) instead of using SRCU callbacks.

While at it, make the code work analogously when SRCU is not enabled
to reduce the differences between the SRCU and non-SRCU cases.

Fixes: 843e600b8a ("driver core: Fix sleeping in invalid context during device link deletion")
Cc: stable <stable@vger.kernel.org>
Reported-by: chenxiang (M) <chenxiang66@hisilicon.com>
Tested-by: chenxiang (M) <chenxiang66@hisilicon.com>
Reviewed-by: Saravana Kannan <saravanak@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/5722787.lOV4Wx5bFT@kreacher
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-03 09:00:34 +02:00
881363cbdd driver core: Extend device_is_dependent()
commit 3d1cf435e2 upstream.

If the device passed as the target (second argument) to
device_is_dependent() is not completely registered (that is, it has
been initialized, but not added yet), but the parent pointer of it
is set, it may be missing from the list of the parent's children
and device_for_each_child() called by device_is_dependent() cannot
be relied on to catch that dependency.

For this reason, modify device_is_dependent() to check the ancestors
of the target device by following its parent pointer in addition to
the device_for_each_child() walk.

Fixes: 9ed9895370 ("driver core: Functional dependencies tracking support")
Reported-by: Stephan Gerhold <stephan@gerhold.net>
Tested-by: Stephan Gerhold <stephan@gerhold.net>
Reviewed-by: Saravana Kannan <saravanak@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/17705994.d592GUb2YH@kreacher
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-27 11:55:18 +01:00
b3bc56e3f5 driver core: Fix device link device name collision
commit e020ff611b upstream.

The device link device's name was of the form:
<supplier-dev-name>--<consumer-dev-name>

This can cause name collision as reported here [1] as device names are
not globally unique. Since device names have to be unique within the
bus/class, add the bus/class name as a prefix to the device names used to
construct the device link device name.

So the devuce link device's name will be of the form:
<supplier-bus-name>:<supplier-dev-name>--<consumer-bus-name>:<consumer-dev-name>

[1] - https://lore.kernel.org/lkml/20201229033440.32142-1-michael@walle.cc/

Fixes: 287905e68d ("driver core: Expose device link details in sysfs")
Cc: stable@vger.kernel.org
Reported-by: Michael Walle <michael@walle.cc>
Tested-by: Michael Walle <michael@walle.cc>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20210110175408.1465657-1-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-27 11:55:18 +01:00
6844bc38c9 Revert "device property: Keep secondary firmware node secondary by type"
commit 47f4469970 upstream.

While commit d5dcce0c41 ("device property: Keep secondary firmware
node secondary by type") describes everything correct in its commit
message, the change it made does the opposite and original commit
c15e1bdda4 ("device property: Fix the secondary firmware node handling
in set_primary_fwnode()") was fully correct.

Revert the former one here and improve documentation in the next patch.

Fixes: d5dcce0c41 ("device property: Keep secondary firmware node secondary by type")
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc: 5.10+ <stable@vger.kernel.org> # 5.10+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-12 20:18:24 +01:00
c26062328e driver: core: Fix list corruption after device_del()
commit 66482f6407 upstream.

The device_links_purge() function (called from device_del()) tries to
remove the links.needs_suppliers list entry, but it's using
list_del(), hence it doesn't initialize after the removal.  This is OK
for normal cases where device_del() is called via device_destroy().
However, it's not guaranteed that the device object will be really
deleted soon after device_del().  In a minor case like HD-audio codec
reconfiguration that re-initializes the device after device_del(), it
may lead to a crash by the corrupted list entry.

As a simple fix, replace list_del() with list_del_init() in order to
make the list intact after the device_del() call.

Fixes: e2ae9bcc4a ("driver core: Add support for linking devices during device addition")
Cc: <stable@vger.kernel.org>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20201208190326.27531-1-tiwai@suse.de
Cc: Saravana Kannan <saravanak@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-30 11:54:26 +01:00
e0e398e204 PM: runtime: Drop runtime PM references to supplier on link removal
While removing a device link, drop the supplier device's runtime PM
usage counter as many times as needed to drop all of the runtime PM
references to it from the consumer in addition to dropping the
consumer's link count.

Fixes: baa8809f60 ("PM / runtime: Optimize the use of device links")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: 5.1+ <stable@vger.kernel.org> # 5.1+
Tested-by: Xiang Chen <chenxiang66@hisilicon.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-02 18:14:07 +01:00
99aed92270 device property: Don't clear secondary pointer for shared primary firmware node
It appears that firmware nodes can be shared between devices. In such case
when a (child) device is about to be deleted, its firmware node may be shared
and ACPI_COMPANION_SET(..., NULL) call for it breaks the secondary link
of the shared primary firmware node.

In order to prevent that, check, if the device has a parent and parent's
firmware node is shared with its child, and avoid crashing the link.

Fixes: c15e1bdda4 ("device property: Fix the secondary firmware node handling in set_primary_fwnode()")
Reported-by: Ferry Toth <fntoth@gmail.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Tested-by: Ferry Toth <fntoth@gmail.com>
Cc: 5.9+ <stable@vger.kernel.org> # 5.9+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-10-27 19:20:03 +01:00
d5dcce0c41 device property: Keep secondary firmware node secondary by type
Behind primary and secondary we understand the type of the nodes
which might define their ordering. However, if primary node gone,
we can't maintain the ordering by definition of the linked list.
Thus, by ordering secondary node becomes first in the list.
But in this case the meaning of it is still secondary (or auxiliary).
The type of the node is maintained by the secondary pointer in it:

	secondary pointer		Meaning
	NULL or valid			primary node
	ERR_PTR(-ENODEV)		secondary node

So, if by some reason we do the following sequence of calls

	set_primary_fwnode(dev, NULL);
	set_primary_fwnode(dev, primary);

we should preserve secondary node.

This concept is supported by the description of set_primary_fwnode()
along with implementation of set_secondary_fwnode(). Hence, fix
the commit c15e1bdda4 to follow this as well.

Fixes: c15e1bdda4 ("device property: Fix the secondary firmware node handling in set_primary_fwnode()")
Cc: Ferry Toth <fntoth@gmail.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Tested-by: Ferry Toth <fntoth@gmail.com>
Cc: 5.9+ <stable@vger.kernel.org> # 5.9+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-10-27 19:18:37 +01:00
54a4c789ca Merge tag 'docs/v5.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull documentation updates from Mauro Carvalho Chehab:
 "A series of patches addressing warnings produced by make htmldocs.
  This includes:

   - kernel-doc markup fixes

   - ReST fixes

   - Updates at the build system in order to support newer versions of
     the docs build toolchain (Sphinx)

  After this series, the number of html build warnings should reduce
  significantly, and building with Sphinx 3.1 or later should now be
  supported (although it is still recommended to use Sphinx 2.4.4).

  As agreed with Jon, I should be sending you a late pull request by the
  end of the merge window addressing remaining issues with docs build,
  as there are a number of warning fixes that depends on pull requests
  that should be happening along the merge window.

  The end goal is to have a clean htmldocs build on Kernel 5.10.

  PS. It should be noticed that Sphinx 3.0 is not currently supported,
  as it lacks support for C domain namespaces. Such feature, needed in
  order to document uAPI system calls with Sphinx 3.x, was added only on
  Sphinx 3.1"

* tag 'docs/v5.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (75 commits)
  PM / devfreq: remove a duplicated kernel-doc markup
  mm/doc: fix a literal block markup
  workqueue: fix a kernel-doc warning
  docs: virt: user_mode_linux_howto_v2.rst: fix a literal block markup
  Input: sparse-keymap: add a description for @sw
  rcu/tree: docs: document bkvcache new members at struct kfree_rcu_cpu
  nl80211: docs: add a description for s1g_cap parameter
  usb: docs: document altmode register/unregister functions
  kunit: test.h: fix a bad kernel-doc markup
  drivers: core: fix kernel-doc markup for dev_err_probe()
  docs: bio: fix a kerneldoc markup
  kunit: test.h: solve kernel-doc warnings
  block: bio: fix a warning at the kernel-doc markups
  docs: powerpc: syscall64-abi.rst: fix a malformed table
  drivers: net: hamradio: fix document location
  net: appletalk: Kconfig: Fix docs location
  dt-bindings: fix references to files converted to yaml
  memblock: get rid of a :c:type leftover
  math64.h: kernel-docs: Convert some markups into normal comments
  media: uAPI: buffer.rst: remove a left-over documentation
  ...
2020-10-16 15:02:21 -07:00
5a32c3413d Merge tag 'dma-mapping-5.10' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping updates from Christoph Hellwig:

 - rework the non-coherent DMA allocator

 - move private definitions out of <linux/dma-mapping.h>

 - lower CMA_ALIGNMENT (Paul Cercueil)

 - remove the omap1 dma address translation in favor of the common code

 - make dma-direct aware of multiple dma offset ranges (Jim Quinlan)

 - support per-node DMA CMA areas (Barry Song)

 - increase the default seg boundary limit (Nicolin Chen)

 - misc fixes (Robin Murphy, Thomas Tai, Xu Wang)

 - various cleanups

* tag 'dma-mapping-5.10' of git://git.infradead.org/users/hch/dma-mapping: (63 commits)
  ARM/ixp4xx: add a missing include of dma-map-ops.h
  dma-direct: simplify the DMA_ATTR_NO_KERNEL_MAPPING handling
  dma-direct: factor out a dma_direct_alloc_from_pool helper
  dma-direct check for highmem pages in dma_direct_alloc_pages
  dma-mapping: merge <linux/dma-noncoherent.h> into <linux/dma-map-ops.h>
  dma-mapping: move large parts of <linux/dma-direct.h> to kernel/dma
  dma-mapping: move dma-debug.h to kernel/dma/
  dma-mapping: remove <asm/dma-contiguous.h>
  dma-mapping: merge <linux/dma-contiguous.h> into <linux/dma-map-ops.h>
  dma-contiguous: remove dma_contiguous_set_default
  dma-contiguous: remove dev_set_cma_area
  dma-contiguous: remove dma_declare_contiguous
  dma-mapping: split <linux/dma-mapping.h>
  cma: decrease CMA_ALIGNMENT lower limit to 2
  firewire-ohci: use dma_alloc_pages
  dma-iommu: implement ->alloc_noncoherent
  dma-mapping: add new {alloc,free}_noncoherent dma_map_ops methods
  dma-mapping: add a new dma_alloc_pages API
  dma-mapping: remove dma_cache_sync
  53c700: convert to dma_alloc_noncoherent
  ...
2020-10-15 14:43:29 -07:00
074b3aad30 drivers: core: fix kernel-doc markup for dev_err_probe()
There are two literal blocks there. Fix the markups, in order
to produce the right html output and solve those warnings:

	./drivers/base/core.c:4218: WARNING: Unexpected indentation.
	./drivers/base/core.c:4222: WARNING: Definition list ends without a blank line; unexpected unindent.
	./drivers/base/core.c:4223: WARNING: Block quote ends without a blank line; unexpected unindent.

Fixes: a787e5400a ("driver core: add device probe log helper")
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-10-15 07:49:48 +02:00
fe151462bd Merge tag 'driver-core-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
 "Here is the "big" set of driver core patches for 5.10-rc1

  They include a lot of different things, all related to the driver core
  and/or some driver logic:

   - sysfs common write functions to make it easier to audit sysfs
     attributes

   - device connection cleanups and fixes

   - devm helpers for a few functions

   - NOIO allocations for when devices are being removed

   - minor cleanups and fixes

  All have been in linux-next for a while with no reported issues"

* tag 'driver-core-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (31 commits)
  regmap: debugfs: use semicolons rather than commas to separate statements
  platform/x86: intel_pmc_core: do not create a static struct device
  drivers core: node: Use a more typical macro definition style for ACCESS_ATTR
  drivers core: Use sysfs_emit for shared_cpu_map_show and shared_cpu_list_show
  mm: and drivers core: Convert hugetlb_report_node_meminfo to sysfs_emit
  drivers core: Miscellaneous changes for sysfs_emit
  drivers core: Reindent a couple uses around sysfs_emit
  drivers core: Remove strcat uses around sysfs_emit and neaten
  drivers core: Use sysfs_emit and sysfs_emit_at for show(device *...) functions
  sysfs: Add sysfs_emit and sysfs_emit_at to format sysfs output
  dyndbg: use keyword, arg varnames for query term pairs
  driver core: force NOIO allocations during unplug
  platform_device: switch to simpler IDA interface
  driver core: platform: Document return type of more functions
  Revert "driver core: Annotate dev_err_probe() with __must_check"
  Revert "test_firmware: Test platform fw loading on non-EFI systems"
  iio: adc: xilinx-xadc: use devm_krealloc()
  hwmon: pmbus: use more devres helpers
  devres: provide devm_krealloc()
  syscore: Use pm_pr_dbg() for syscore_{suspend,resume}()
  ...
2020-10-14 16:09:32 -07:00
d5660df4a5 Merge branch 'akpm' (patches from Andrew)
Merge misc updates from Andrew Morton:
 "181 patches.

  Subsystems affected by this patch series: kbuild, scripts, ntfs,
  ocfs2, vfs, mm (slab, slub, kmemleak, dax, debug, pagecache, fadvise,
  gup, swap, memremap, memcg, selftests, pagemap, mincore, hmm, dma,
  memory-failure, vmallo and migration)"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (181 commits)
  mm/migrate: remove obsolete comment about device public
  mm/migrate: remove cpages-- in migrate_vma_finalize()
  mm, oom_adj: don't loop through tasks in __set_oom_adj when not necessary
  memblock: use separate iterators for memory and reserved regions
  memblock: implement for_each_reserved_mem_region() using __next_mem_region()
  memblock: remove unused memblock_mem_size()
  x86/setup: simplify reserve_crashkernel()
  x86/setup: simplify initrd relocation and reservation
  arch, drivers: replace for_each_membock() with for_each_mem_range()
  arch, mm: replace for_each_memblock() with for_each_mem_pfn_range()
  memblock: reduce number of parameters in for_each_mem_range()
  memblock: make memblock_debug and related functionality private
  memblock: make for_each_memblock_type() iterator private
  mircoblaze: drop unneeded NUMA and sparsemem initializations
  riscv: drop unneeded node initialization
  h8300, nds32, openrisc: simplify detection of memory extents
  arm64: numa: simplify dummy_numa_init()
  arm, xtensa: simplify initialization of high memory pages
  dma-contiguous: simplify cma_early_percent_memory()
  KVM: PPC: Book3S HV: simplify kvm_cma_reserve()
  ...
2020-10-14 09:57:24 -07:00
c77f520db8 drivers/base: make device_find_child_by_name() compatible with sysfs inputs
Use sysfs_streq() in device_find_child_by_name() to allow it to use a
sysfs input string that might contain a trailing newline.

The other "device by name" interfaces,
{bus,driver,class}_find_device_by_name(), already account for sysfs
strings.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Brice Goglin <Brice.Goglin@inria.fr>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: David Airlie <airlied@linux.ie>
Cc: David Hildenbrand <david@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Hulk Robot <hulkci@huawei.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Jason Yan <yanaijie@huawei.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Cc: Jia He <justin.he@arm.com>
Cc: Joao Martins <joao.m.martins@oracle.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/159643102106.4062302.12229802117645312104.stgit@dwillia2-desk3.amr.corp.intel.com
Link: https://lkml.kernel.org/r/160106114576.30709.2960091665444712180.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13 18:38:28 -07:00
d594d8f411 Merge tag 'printk-for-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux
Pull printk updates from Petr Mladek:
 "The big new thing is the fully lockless ringbuffer implementation,
  including the support for continuous lines. It will allow to store and
  read messages in any situation wihtout the risk of deadlocks and
  without the need of temporary per-CPU buffers.

  The access is still serialized by logbuf_lock. It synchronizes few
  more operations, for example, temporary buffer for formatting the
  message, syslog and kmsg_dump operations. The lock removal is being
  discussed and should be ready for the next release.

  The continuous lines are handled exactly the same way as before to
  avoid regressions in user space. It means that they are appended to
  the last message when the caller is the same. Only the last message
  can be extended.

  The data ring includes plain text of the messages. Except for an
  integer at the beginning of each message that points back to the
  descriptor ring with other metadata.

  The dictionary has to stay. journalctl uses it to filter the log. It
  allows to show messages related to a given device. The dictionary
  values are stored in the descriptor ring with the other metadata.

  This is the first part of the printk rework as discussed at Plumbers
  2019, see https://lore.kernel.org/r/87k1acz5rx.fsf@linutronix.de. The
  next big step will be handling consoles by kthreads during the normal
  system operation. It will require special handling of situations when
  the kthreads could not get scheduled, for example, early boot,
  suspend, panic.

  Other changes:

   - Add John Ogness as a reviewer for printk subsystem. He is author of
     the rework and is familiar with the code and history.

   - Fix locking in serial8250_do_startup() to prevent lockdep report.

   - Few code cleanups"

* tag 'printk-for-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux: (27 commits)
  printk: Use fallthrough pseudo-keyword
  printk: reduce setup_text_buf size to LOG_LINE_MAX
  printk: avoid and/or handle record truncation
  printk: remove dict ring
  printk: move dictionary keys to dev_printk_info
  printk: move printk_info into separate array
  printk: reimplement log_cont using record extension
  printk: ringbuffer: add finalization/extension support
  printk: ringbuffer: change representation of states
  printk: ringbuffer: clear initial reserved fields
  printk: ringbuffer: add BLK_DATALESS() macro
  printk: ringbuffer: relocate get_data()
  printk: ringbuffer: avoid memcpy() on state_var
  printk: ringbuffer: fix setting state in desc_read()
  kernel.h: Move oops_in_progress to printk.h
  scripts/gdb: update for lockless printk ringbuffer
  scripts/gdb: add utils.read_ulong()
  docs: vmcoreinfo: add lockless printk ringbuffer vmcoreinfo
  printk: reduce LOG_BUF_SHIFT range for H8300
  printk: ringbuffer: support dataless records
  ...
2020-10-13 15:58:10 -07:00
70333f4ff9 Merge branch 'printk-rework' into for-linus 2020-10-12 13:01:37 +02:00
948b3edba8 drivers core: Miscellaneous changes for sysfs_emit
Change additional instances that could use sysfs_emit and sysfs_emit_at
that the coccinelle script could not convert.

o macros creating show functions with ## concatenation
o unbound sprintf uses with buf+len for start of output to sysfs_emit_at
o returns with ?: tests and sprintf to sysfs_emit
o sysfs output with struct class * not struct device * arguments

Miscellanea:

o remove unnecessary initializations around these changes
o consistently use int len for return length of show functions
o use octal permissions and not S_<FOO>
o rename a few show function names so DEVICE_ATTR_<FOO> can be used
o use DEVICE_ATTR_ADMIN_RO where appropriate
o consistently use const char *output for strings
o checkpatch/style neatening

Signed-off-by: Joe Perches <joe@perches.com>
Link: https://lore.kernel.org/r/8bc24444fe2049a9b2de6127389b57edfdfe324d.1600285923.git.joe@perches.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-02 13:12:07 +02:00
973c39115c drivers core: Remove strcat uses around sysfs_emit and neaten
strcat is no longer necessary for sysfs_emit and sysfs_emit_at uses.

Convert the strcat uses to sysfs_emit calls and neaten other block
uses of direct returns to use an intermediate const char *.

Signed-off-by: Joe Perches <joe@perches.com>
Link: https://lore.kernel.org/r/5d606519698ce4c8f1203a2b35797d8254c6050a.1600285923.git.joe@perches.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-02 13:09:10 +02:00
aa838896d8 drivers core: Use sysfs_emit and sysfs_emit_at for show(device *...) functions
Convert the various sprintf fmaily calls in sysfs device show functions
to sysfs_emit and sysfs_emit_at for PAGE_SIZE buffer safety.

Done with:

$ spatch -sp-file sysfs_emit_dev.cocci --in-place --max-width=80 .

And cocci script:

$ cat sysfs_emit_dev.cocci
@@
identifier d_show;
identifier dev, attr, buf;
@@

ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	<...
	return
-	sprintf(buf,
+	sysfs_emit(buf,
	...);
	...>
}

@@
identifier d_show;
identifier dev, attr, buf;
@@

ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	<...
	return
-	snprintf(buf, PAGE_SIZE,
+	sysfs_emit(buf,
	...);
	...>
}

@@
identifier d_show;
identifier dev, attr, buf;
@@

ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	<...
	return
-	scnprintf(buf, PAGE_SIZE,
+	sysfs_emit(buf,
	...);
	...>
}

@@
identifier d_show;
identifier dev, attr, buf;
expression chr;
@@

ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	<...
	return
-	strcpy(buf, chr);
+	sysfs_emit(buf, chr);
	...>
}

@@
identifier d_show;
identifier dev, attr, buf;
identifier len;
@@

ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	<...
	len =
-	sprintf(buf,
+	sysfs_emit(buf,
	...);
	...>
	return len;
}

@@
identifier d_show;
identifier dev, attr, buf;
identifier len;
@@

ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	<...
	len =
-	snprintf(buf, PAGE_SIZE,
+	sysfs_emit(buf,
	...);
	...>
	return len;
}

@@
identifier d_show;
identifier dev, attr, buf;
identifier len;
@@

ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	<...
	len =
-	scnprintf(buf, PAGE_SIZE,
+	sysfs_emit(buf,
	...);
	...>
	return len;
}

@@
identifier d_show;
identifier dev, attr, buf;
identifier len;
@@

ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	<...
-	len += scnprintf(buf + len, PAGE_SIZE - len,
+	len += sysfs_emit_at(buf, len,
	...);
	...>
	return len;
}

@@
identifier d_show;
identifier dev, attr, buf;
expression chr;
@@

ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	...
-	strcpy(buf, chr);
-	return strlen(buf);
+	return sysfs_emit(buf, chr);
}

Signed-off-by: Joe Perches <joe@perches.com>
Link: https://lore.kernel.org/r/3d033c33056d88bbe34d4ddb62afd05ee166ab9a.1600285923.git.joe@perches.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-02 13:09:10 +02:00
8c1c6c7588 Merge branch 'master' of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into dma-mapping-for-next
Pull in the latest 5.9 tree for the commit to revert the
V4L2_FLAG_MEMORY_NON_CONSISTENT uapi addition.
2020-09-25 06:19:19 +02:00
74caba7f2a printk: move dictionary keys to dev_printk_info
Dictionaries are only used for SUBSYSTEM and DEVICE properties. The
current implementation stores the property names each time they are
used. This requires more space than otherwise necessary. Also,
because the dictionary entries are currently considered optional,
it cannot be relied upon that they are always available, even if the
writer wanted to store them. These issues will increase should new
dictionary properties be introduced.

Rather than storing the subsystem and device properties in the
dict ring, introduce a struct dev_printk_info with separate fields
to store only the property values. Embed this struct within the
struct printk_info to provide guaranteed availability.

Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/87mu1jl6ne.fsf@jogness.linutronix.de
2020-09-22 11:27:48 +02:00
e0d072782c dma-mapping: introduce DMA range map, supplanting dma_pfn_offset
The new field 'dma_range_map' in struct device is used to facilitate the
use of single or multiple offsets between mapping regions of cpu addrs and
dma addrs.  It subsumes the role of "dev->dma_pfn_offset" which was only
capable of holding a single uniform offset and had no region bounds
checking.

The function of_dma_get_range() has been modified so that it takes a single
argument -- the device node -- and returns a map, NULL, or an error code.
The map is an array that holds the information regarding the DMA regions.
Each range entry contains the address offset, the cpu_start address, the
dma_start address, and the size of the region.

of_dma_configure() is the typical manner to set range offsets but there are
a number of ad hoc assignments to "dev->dma_pfn_offset" in the kernel
driver code.  These cases now invoke the function
dma_direct_set_offset(dev, cpu_addr, dma_addr, size).

Signed-off-by: Jim Quinlan <james.quinlan@broadcom.com>
[hch: various interface cleanups]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
2020-09-17 18:43:56 +02:00
b85300173d driver core: force NOIO allocations during unplug
There is one overlooked situation under which a driver must not do IO to
allocate memory. You cannot do that while disconnecting a device. A
device being disconnected is no longer functional in most cases, yet IO
may fail only when the handler runs.

Signed-off-by: Oliver Neukum <oneukum@suse.com>
Link: https://lore.kernel.org/r/20200916191544.5104-1-oneukum@suse.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-17 08:40:56 +02:00
20a7b6be05 Merge tag 'driver-core-5.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core fixes from Greg KH:
 "Here are some small driver core and debugfs fixes for 5.9-rc5

  Included in here are:

   - firmware loader memory leak fix

   - firmware loader testing fixes for non-EFI systems

   - device link locking fixes found by lockdep

   - kobject_del() bugfix that has been affecting some callers

   - debugfs minor fix

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'driver-core-5.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  test_firmware: Test platform fw loading on non-EFI systems
  PM: <linux/device.h>: fix @em_pd kernel-doc warning
  kobject: Drop unneeded conditional in __kobject_del()
  driver core: Fix device_pm_lock() locking for device links
  MAINTAINERS: Add the security document to SECURITY CONTACT
  driver code: print symbolic error code
  debugfs: Fix module state check condition
  kobject: Restore old behaviour of kobject_del(NULL)
  firmware_loader: fix memory leak for paged buffer
2020-09-13 09:02:59 -07:00
6b57b15abe driver core: Fix device_pm_lock() locking for device links
This commit fixes two issues:

1. The lockdep warning reported by Dong Aisheng <dongas86@gmail.com> [1].

It is a warning about a cycle (dpm_list_mtx --> kn->active#3 --> fw_lock)
that was introduced when device-link devices were added to expose device
link information in sysfs.

The patch that "introduced" this cycle can't be reverted because it's fixes
a real SRCU issue and also ensures that the device-link device is deleted
as soon as the device-link is deleted. This is important to avoid sysfs
name collisions if the device-link is create again immediately (this can
happen a lot with deferred probing).

2. Inconsistency in grabbing device_pm_lock() during device link deletion

Some device link deletion code paths grab device_pm_lock(), while others
don't.  The device_pm_lock() is grabbed during device_link_add() because it
checks if the supplier is in the dpm_list and also reorders the dpm_list.
However, when a device link is deleted, it does not do either of those and
therefore device_pm_lock() is not necessary. Dropping the device_pm_lock()
in all the device link deletion paths removes the inconsistency in locking.

Thanks to Stephen Boyd for helping me understand the lockdep splat.

Fixes: 843e600b8a ("driver core: Fix sleeping in invalid context during device link deletion")
[1] - https://lore.kernel.org/lkml/CAA+hA=S4eAreb7vo69LAXSk2t5=DEKNxHaiY1wSpk4xTp9urLg@mail.gmail.com/
Reported-by: Dong Aisheng <dongas86@gmail.com>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Tested-by: Peng Fan <peng.fan@nxp.com>
Link: https://lore.kernel.org/r/20200901184445.1736658-1-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-04 18:21:35 +02:00
693a8e9365 driver code: print symbolic error code
dev_err_probe() prepends the message with an error code. Let's make it
more readable by translating the code to a more recognisable symbol.

Fixes: a787e5400a ("driver core: add device probe log helper")
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Link: https://lore.kernel.org/r/ea3f973e4708919573026fdce52c264db147626d.1598630856.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-04 18:14:52 +02:00
c15e1bdda4 device property: Fix the secondary firmware node handling in set_primary_fwnode()
When the primary firmware node pointer is removed from a
device (set to NULL) the secondary firmware node pointer,
when it exists, is made the primary node for the device.
However, the secondary firmware node pointer of the original
primary firmware node is never cleared (set to NULL).

To avoid situation where the secondary firmware node pointer
is pointing to a non-existing object, clearing it properly
when the primary node is removed from a device in
set_primary_fwnode().

Fixes: 97badf873a ("device property: Make it possible to use secondary firmware nodes")
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-08-21 20:26:21 +02:00
441977979a Merge tag 'devicetree-for-5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux
Pull Devicetree updates from Rob Herring:

 - Improve device links cycle detection and breaking. Add more bindings
   for device link dependencies.

 - Refactor parsing 'no-map' in __reserved_mem_alloc_size()

 - Improve DT unittest 'ranges' and 'dma-ranges' test case to check
   differing cell sizes

 - Various http to https link conversions

 - Add a schema check to prevent 'syscon' from being used by itself
   without a more specific compatible

 - A bunch more DT binding conversions to schema

* tag 'devicetree-for-5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (55 commits)
  of: reserved-memory: remove duplicated call to of_get_flat_dt_prop() for no-map node
  of: unittest: Use bigger address cells to catch parser regressions
  dt-bindings: memory-controllers: Convert mmdc to json-schema
  dt-bindings: mtd: Convert imx nand to json-schema
  dt-bindings: mtd: Convert gpmi nand to json-schema
  dt-bindings: iio: io-channel-mux: Fix compatible string in example code
  of: property: Add device link support for pinctrl-0 through pinctrl-8
  of: property: Add device link support for multiple DT bindings
  dt-bindings: phy: ti: phy-gmii-sel: convert bindings to json-schema
  dt-bindings: mux: mux.h: drop a duplicated word
  dt-bindings: misc: Convert olpc,xo1.75-ec to json-schema
  dt-bindings: aspeed-lpc: Replace HTTP links with HTTPS ones
  dt-bindings: drm/bridge: Replace HTTP links with HTTPS ones
  drm/tilcdc: Replace HTTP links with HTTPS ones
  dt-bindings: iommu: renesas,ipmmu-vmsa: Add r8a774e1 support
  dt-bindings: fpga: Replace HTTP links with HTTPS ones
  dt-bindings: virtio: Replace HTTP links with HTTPS ones
  dt-bindings: media: imx274: Add optional input clock and supplies
  dt-bindings: i2c-gpio: Use 'deprecated' keyword on deprecated properties
  dt-bindings: interrupt-controller: Fix typos in loongson,liointc.yaml
  ...
2020-08-05 13:02:45 -07:00
d090b70ede driver core: add deferring probe reason to devices_deferred property
/sys/kernel/debug/devices_deferred property contains list of deferred devices.
This list does not contain reason why the driver deferred probe, the patch
improves it.
The natural place to set the reason is dev_err_probe function introduced
recently, ie. if dev_err_probe will be called with -EPROBE_DEFER instead of
printk the message will be attached to a deferred device and printed when user
reads devices_deferred property.

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Rafael J. Wysocki <rafael@kernel.org>
Link: https://lore.kernel.org/r/20200713144324.23654-3-a.hajda@samsung.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-30 09:03:43 +02:00
a787e5400a driver core: add device probe log helper
During probe every time driver gets resource it should usually check for
error printk some message if it is not -EPROBE_DEFER and return the error.
This pattern is simple but requires adding few lines after any resource
acquisition code, as a result it is often omitted or implemented only
partially.
dev_err_probe helps to replace such code sequences with simple call,
so code:
	if (err != -EPROBE_DEFER)
		dev_err(dev, ...);
	return err;
becomes:
	return dev_err_probe(dev, err, ...);

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Reviewed-by: Rafael J. Wysocki <rafael@kernel.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20200713144324.23654-2-a.hajda@samsung.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-30 09:03:43 +02:00
90b109d50d driver core: Change delimiter in devlink device's name to "--"
The devlink device name is of the form "supplier:consumer". But ":" is
fairly common in device names and makes it visually hard to distinguish
supplier and consumer. So, replace it with "--" to make it easier.

Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20200724180523.1393383-1-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-24 20:55:25 +02:00
843e600b8a driver core: Fix sleeping in invalid context during device link deletion
Marek and Guenter reported that commit 287905e68d ("driver core:
Expose device link details in sysfs") caused sleeping/scheduling while
atomic warnings.

BUG: sleeping function called from invalid context at kernel/locking/mutex.c:935
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 12, name: kworker/0:1
2 locks held by kworker/0:1/12:
  #0: ee8074a8 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x174/0x7dc
  #1: ee921f20 ((work_completion)(&sdp->work)){+.+.}-{0:0}, at: process_one_work+0x174/0x7dc
Preemption disabled at:
[<c01b10f0>] srcu_invoke_callbacks+0xc0/0x154
----- 8< ----- SNIP
[<c064590c>] (device_del) from [<c0645c9c>] (device_unregister+0x24/0x64)
[<c0645c9c>] (device_unregister) from [<c01b10fc>] (srcu_invoke_callbacks+0xcc/0x154)
[<c01b10fc>] (srcu_invoke_callbacks) from [<c01493c4>] (process_one_work+0x234/0x7dc)
[<c01493c4>] (process_one_work) from [<c01499b0>] (worker_thread+0x44/0x51c)
[<c01499b0>] (worker_thread) from [<c0150bf4>] (kthread+0x158/0x1a0)
[<c0150bf4>] (kthread) from [<c0100114>] (ret_from_fork+0x14/0x20)
Exception stack(0xee921fb0 to 0xee921ff8)

This was caused by the device link device being released in the context
of srcu_invoke_callbacks().  There is no need to wait till the RCU
callback to release the device link device.  So release the device
earlier and move the call_srcu() into the device release code. That way,
the memory will get freed only after the device is released AND the RCU
callback is called.

Fixes: 287905e68d ("driver core: Expose device link details in sysfs")
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20200716214523.2924704-1-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-23 09:20:21 +02:00
6bdb486c5a Merge 5.8-rc6 into driver-core-next
We need the driver core fixes in here too.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-20 09:31:35 +02:00
da6d647598 driver core: Add waiting_for_supplier sysfs file for devices
This would be useful to check if a device is not probing because it's
waiting for a supplier to be added and then linked to before it can
probe.

To reduce sysfs clutter, this file is added only if it can ever be 1.
So, if fw_devlink is disabled or set to permissive, this file is not
added. Also, this file is removed once the device probes as it's no
longer relevant.

Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20200521191800.136035-4-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-10 15:24:56 +02:00
287905e68d driver core: Expose device link details in sysfs
It's helpful to be able to look at device link details from sysfs. So,
expose it in sysfs.

Say device-A is supplier of device-B. These are the additional files
this patch would create:

/sys/class/devlink/device-A:device-B/
	auto_remove_on
	consumer/ -> .../device-B/
	runtime_pm
	status
	supplier/ -> .../device-A/
	sync_state_only

/sys/devices/.../device-A/
	consumer:device-B/ -> /sys/class/devlink/device-A:device-B/

/sys/devices/.../device-B/
	supplier:device-A/ -> /sys/class/devlink/device-A:device-B/

That way:
To get a list of all the device link in the system:
ls /sys/class/devlink/

To get the consumer names and links of a device:
ls -d /sys/devices/.../device-X/consumer:*

To get the supplier names and links of a device:
ls -d /sys/devices/.../device-X/supplier:*

Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20200521191800.136035-2-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-10 15:24:56 +02:00
2451e74647 driver core: Avoid deferred probe due to fw_devlink_pause/resume()
With the earlier patch in this series, all devices that deferred probe
due to fw_devlink_pause() will have their probes delayed till the
deferred probe thread is kicked off during late_initcall. This will also
affect all their consumers.

This delayed probing in unnecessary. So this patch just keeps track of
the devices that had their probe deferred due to fw_devlink_pause() and
attempts to probe them once during fw_devlink_resume().

Fixes: 716a7a2596 ("driver core: fw_devlink: Add support for batching fwnode parsing")
Signed-off-by: Saravana Kannan <saravanak@google.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200701194259.3337652-4-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-10 15:20:38 +02:00
ec7bd78498 driver core: Rename dev_links_info.defer_sync to defer_hook
The defer_sync field is used as a hook to add the device to the
deferred_sync list. Rename it so that it's more meaningful for the next
patch that'll also use this field as a hook to a deferred_fw_devlink
list.

Signed-off-by: Saravana Kannan <saravanak@google.com>
Reviewed-by: Rafael J. Wysocki <rafael@kernel.org>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200701194259.3337652-3-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-10 15:20:38 +02:00
cec72f3efc driver core: Don't do deferred probe in parallel with kernel_init thread
The current deferred probe implementation can mess up suspend/resume
ordering if deferred probe thread is kicked off in parallel with the
main initcall thread (kernel_init thread) [1].

For example:

Say device-B is a consumer of device-A.

Initcall thread					Deferred probe thread
===============					=====================
1. device-A is added.
2. device-B is added.
3. dpm_list is now [device-A, device-B].
4. driver-A defers probe of device-A.
						5. device-A is moved to
						   end of dpm_list
						6. dpm_list is now
						   [device-B, device-A]
7. driver-B is registereed and probes device-B.
8. dpm_list stays as [device-B, device-A].

The reverse order of dpm_list is used for suspend. So in this case
device-A would incorrectly get suspended before device-B.

Commit 716a7a2596 ("driver core: fw_devlink: Add support for batching
fwnode parsing") kicked off the deferred probe thread early during boot
to run in parallel with the initcall thread and caused suspend/resume
regressions.  This patch removes the parallel run of the deferred probe
thread to avoid the suspend/resume regressions.

[1] - https://lore.kernel.org/lkml/CAGETcx8W96KAw-d_siTX4qHB_-7ddk0miYRDQeHE6E0_8qx-6Q@mail.gmail.com/

Fixes: 716a7a2596 ("driver core: fw_devlink: Add support for batching fwnode parsing")
Signed-off-by: Saravana Kannan <saravanak@google.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200701194259.3337652-2-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-10 15:20:38 +02:00
7d34ca3854 driver core: Add device_is_dependent() to linux/device.h
DT implementation of fw_devlink needs this function to detect cycles. So
make it available.

Signed-off-by: Saravana Kannan <saravanak@google.com>
Tested-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>
2020-06-17 16:10:56 -06:00
f558b8364e Merge tag 'driver-core-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
 "Here is the set of driver core patches for 5.8-rc1.

  Not all that huge this release, just a number of small fixes and
  updates:

   - software node fixes

   - kobject now sends KOBJ_REMOVE when it is removed from sysfs, not
     when it is removed from memory (which could come much later)

   - device link additions and fixes based on testing on more devices

   - firmware core cleanups

   - other minor changes, full details in the shortlog

  All have been in linux-next for a while with no reported issues"

* tag 'driver-core-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (23 commits)
  driver core: Update device link status correctly for SYNC_STATE_ONLY links
  firmware_loader: change enum fw_opt to u32
  software node: implement software_node_unregister()
  kobject: send KOBJ_REMOVE uevent when the object is removed from sysfs
  driver core: Remove unnecessary is_fwnode_dev variable in device_add()
  drivers property: When no children in primary, try secondary
  driver core: platform: Fix spelling errors in platform.c
  driver core: Remove check in driver_deferred_probe_force_trigger()
  of: platform: Batch fwnode parsing when adding all top level devices
  driver core: fw_devlink: Add support for batching fwnode parsing
  driver core: Look for waiting consumers only for a fwnode's primary device
  driver core: Move code to the right part of the file
  Revert "Revert "driver core: Set fw_devlink to "permissive" behavior by default""
  drivers: base: Fix NULL pointer exception in __platform_driver_probe() if a driver developer is foolish
  firmware_loader: move fw_fallback_config to a private kernel symbol namespace
  driver core: Add missing '\n' in log messages
  driver/base/soc: Use kobj_to_dev() API
  Add documentation on meaning of -EPROBE_DEFER
  driver core: platform: remove redundant assignment to variable ret
  debugfs: Use the correct style for SPDX License Identifier
  ...
2020-06-07 10:53:36 -07:00
750a02ab8d Merge tag 'for-5.8/block-2020-06-01' of git://git.kernel.dk/linux-block
Pull block updates from Jens Axboe:
 "Core block changes that have been queued up for this release:

   - Remove dead blk-throttle and blk-wbt code (Guoqing)

   - Include pid in blktrace note traces (Jan)

   - Don't spew I/O errors on wouldblock termination (me)

   - Zone append addition (Johannes, Keith, Damien)

   - IO accounting improvements (Konstantin, Christoph)

   - blk-mq hardware map update improvements (Ming)

   - Scheduler dispatch improvement (Salman)

   - Inline block encryption support (Satya)

   - Request map fixes and improvements (Weiping)

   - blk-iocost tweaks (Tejun)

   - Fix for timeout failing with error injection (Keith)

   - Queue re-run fixes (Douglas)

   - CPU hotplug improvements (Christoph)

   - Queue entry/exit improvements (Christoph)

   - Move DMA drain handling to the few drivers that use it (Christoph)

   - Partition handling cleanups (Christoph)"

* tag 'for-5.8/block-2020-06-01' of git://git.kernel.dk/linux-block: (127 commits)
  block: mark bio_wouldblock_error() bio with BIO_QUIET
  blk-wbt: rename __wbt_update_limits to wbt_update_limits
  blk-wbt: remove wbt_update_limits
  blk-throttle: remove tg_drain_bios
  blk-throttle: remove blk_throtl_drain
  null_blk: force complete for timeout request
  blk-mq: drain I/O when all CPUs in a hctx are offline
  blk-mq: add blk_mq_all_tag_iter
  blk-mq: open code __blk_mq_alloc_request in blk_mq_alloc_request_hctx
  blk-mq: use BLK_MQ_NO_TAG in more places
  blk-mq: rename BLK_MQ_TAG_FAIL to BLK_MQ_NO_TAG
  blk-mq: move more request initialization to blk_mq_rq_ctx_init
  blk-mq: simplify the blk_mq_get_request calling convention
  blk-mq: remove the bio argument to ->prepare_request
  nvme: force complete cancelled requests
  blk-mq: blk-mq: provide forced completion method
  block: fix a warning when blkdev.h is included for !CONFIG_BLOCK builds
  block: blk-crypto-fallback: remove redundant initialization of variable err
  block: reduce part_stat_lock() scope
  block: use __this_cpu_add() instead of access by smp_processor_id()
  ...
2020-06-02 15:29:19 -07:00
a5a82e0a59 Merge tag 'platform-drivers-x86-v5.8-1' of git://git.infradead.org/linux-platform-drivers-x86
Pull x86 platform driver updates from Andy Shevchenko:

 - Add a support of the media keys on the ASUS laptop UX325JA/UX425JA

 - ASUS WMI driver can now handle 2-in-1 models T100TA, T100CHI, T100HA,
   T200TA

 - Big refactoring of Intel SCU driver with Elkhart Lake support has
   been added

 - Slim Bootloarder firmware update signaling WMI driver has been added

 - Thinkpad ACPI driver can handle dual fan configuration on new P and X
   models

 - Touchscreen DMI driver has been extended to support
    - MP-man MPWIN895CL tablet
    - ONDA V891 v5 tablet
    - techBite Arc 11.6
    - Trekstor Twin 10.1
    - Trekstor Yourbook C11B
    - Vinga J116

 - Virtual Button driver got a few fixes to detect mode of 2-in-1 tablet
   models

 - Intel Speed Select tools update

 - Plenty of small cleanups here and there

* tag 'platform-drivers-x86-v5.8-1' of git://git.infradead.org/linux-platform-drivers-x86: (89 commits)
  platform/x86: dcdbas: Check SMBIOS for protected buffer address
  platform/x86: asus_wmi: Reserve more space for struct bias_args
  platform/x86: intel-vbtn: Only blacklist SW_TABLET_MODE on the 9 / "Laptop" chasis-type
  platform/x86: intel-hid: Add a quirk to support HP Spectre X2 (2015)
  platform/x86: touchscreen_dmi: Update Trekstor Twin 10.1 entry
  platform/x86: touchscreen_dmi: Add info for the Trekstor Yourbook C11B
  platform/x86: hp-wmi: Introduce HPWMI_POWER_FW_OR_HW as convenient shortcut
  platform/x86: hp-wmi: Convert simple_strtoul() to kstrtou32()
  platform/x86: hp-wmi: Refactor postcode_store() to follow standard patterns
  platform/x86: acerhdf: replace space by * in modalias
  platform/x86: ISST: Increase timeout
  tools/power/x86/intel-speed-select: Fix invalid core mask
  tools/power/x86/intel-speed-select: Increase CPU count
  tools/power/x86/intel-speed-select: Fix json perf-profile output output
  platform/x86: dell-wmi: Ignore keyboard attached / detached events
  platform/x86: dell-laptop: don't register micmute LED if there is no token
  platform/x86: thinkpad_acpi: Replace custom approach by kstrtoint()
  platform/x86: thinkpad_acpi: Use strndup_user() in dispatch_proc_write()
  platform/x86: thinkpad_acpi: Replace next_cmd(&buf) with strsep(&buf, ",")
  platform/x86: intel-vbtn: Detect switch position before registering the input-device
  ...
2020-06-02 12:56:58 -07:00
b23c4771ff Merge tag 'docs-5.8' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
 "A fair amount of stuff this time around, dominated by yet another
  massive set from Mauro toward the completion of the RST conversion. I
  *really* hope we are getting close to the end of this. Meanwhile,
  those patches reach pretty far afield to update document references
  around the tree; there should be no actual code changes there. There
  will be, alas, more of the usual trivial merge conflicts.

  Beyond that we have more translations, improvements to the sphinx
  scripting, a number of additions to the sysctl documentation, and lots
  of fixes"

* tag 'docs-5.8' of git://git.lwn.net/linux: (130 commits)
  Documentation: fixes to the maintainer-entry-profile template
  zswap: docs/vm: Fix typo accept_threshold_percent in zswap.rst
  tracing: Fix events.rst section numbering
  docs: acpi: fix old http link and improve document format
  docs: filesystems: add info about efivars content
  Documentation: LSM: Correct the basic LSM description
  mailmap: change email for Ricardo Ribalda
  docs: sysctl/kernel: document unaligned controls
  Documentation: admin-guide: update bug-hunting.rst
  docs: sysctl/kernel: document ngroups_max
  nvdimm: fixes to maintainter-entry-profile
  Documentation/features: Correct RISC-V kprobes support entry
  Documentation/features: Refresh the arch support status files
  Revert "docs: sysctl/kernel: document ngroups_max"
  docs: move locking-specific documents to locking/
  docs: move digsig docs to the security book
  docs: move the kref doc into the core-api book
  docs: add IRQ documentation at the core-api book
  docs: debugging-via-ohci1394.txt: add it to the core-api book
  docs: fix references for ipmi.rst file
  ...
2020-06-01 15:45:27 -07:00
8c3e315d42 driver core: Update device link status correctly for SYNC_STATE_ONLY links
When SYNC_STATE_ONLY support was added in commit 05ef983e0d ("driver
core: Add device link support for SYNC_STATE_ONLY flag"),
SYNC_STATE_ONLY links were treated similar to STATELESS links in terms
of not blocking consumer probe if the supplier hasn't probed yet.

That caused a SYNC_STATE_ONLY device link's status to not get updated.
Since SYNC_STATE_ONLY device link is no longer useful once the
consumer probes, commit 21c27f0658 ("driver core: Fix
SYNC_STATE_ONLY device link implementation") addresses the status
update issue by deleting the SYNC_STATE_ONLY device link instead of
complicating the status update code.

However, there are still some cases where we need to update the status
of a SYNC_STATE_ONLY device link. This is because a SYNC_STATE_ONLY
device link can later get converted into a normal MANAGED device link
when a normal MANAGED device link is created between a supplier and
consumer that already have a SYNC_STATE_ONLY device link between them.

If a SYNC_STATE_ONLY device link's status isn't maintained correctly
till it's converted to a normal MANAGED device link, then the normal
MANAGED device link will end up with a wrong link status. This can cause
a warning stack trace[1] when the consumer device probes successfully.

This commit fixes the SYNC_STATE_ONLY device link status update issue
where it wouldn't transition correctly from DL_STATE_DORMANT or
DL_STATE_AVAILABLE to DL_STATE_CONSUMER_PROBE. It also resets the status
back to DL_STATE_DORMANT or DL_STATE_AVAILABLE if the consumer probe
fails.

[1] - https://lore.kernel.org/lkml/20200522204120.3b3c9ed6@apollo/
Fixes: 05ef983e0d ("driver core: Add device link support for SYNC_STATE_ONLY flag")
Fixes: 21c27f0658 ("driver core: Fix SYNC_STATE_ONLY device link implementation")
Reported-by: Michael Walle <michael@walle.cc>
Tested-by: Michael Walle <michael@walle.cc>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Reviewed-by: Rafael J. Wysocki <rrafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/20200526220928.49939-1-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-27 12:20:47 +02:00