commit e912e685f3 upstream.
This phone needs to be handled by a specialised firmware tool
and is reported to crash irrevocably if cdc-acm takes it.
Signed-off-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 327b882d3b upstream.
Commit f79b0d9c22 ("staging: speakup: Fixed warning <linux/serial.h>
instead of <asm/serial.h>") broke the port information in the speakup
driver: SERIAL_PORT_DFNS only gets defined if asm/serial.h is included,
and no other header includes asm/serial.h.
We here make sure serialio.c does get the arch-specific definition of
SERIAL_PORT_DFNS from asm/serial.h, if any.
Along the way, this makes sure that we do have information for the
requested serial port number (index)
Fixes: f79b0d9c22 ("staging: speakup: Fixed warning <linux/serial.h> instead of <asm/serial.h>")
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit cd8140c673 upstream.
Commit d15f9d694b ("libceph: check data_len in ->alloc_msg()")
mistakenly bumped the log level on the "tid %llu unknown, skipping"
message. Turn it back into a dout() - stray replies are perfectly
normal when OSDs flap, crash, get killed for testing purposes, etc.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit dbc0d3caff upstream.
ceph_msg_footer is 21 bytes long, while ceph_msg_footer_old is only 13.
Don't skip too much when CEPH_FEATURE_MSG_AUTH isn't negotiated.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e7a88e82fe upstream.
The contract between try_read() and try_write() is that when called
each processes as much data as possible. When instructed by osd_client
to skip a message, try_read() is violating this contract by returning
after receiving and discarding a single message instead of checking for
more. try_write() then gets a chance to write out more requests,
generating more replies/skips for try_read() to handle, forcing the
messenger into a starvation loop.
Reported-by: Varada Kari <Varada.Kari@sandisk.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Tested-by: Varada Kari <Varada.Kari@sandisk.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 67645d7619 upstream.
There are a number of problems with revoking a "was sending" message:
(1) We never make any attempt to revoke data - only kvecs contibute to
con->out_skip. However, once the header (envelope) is written to the
socket, our peer learns data_len and sets itself to expect at least
data_len bytes to follow front or front+middle. If ceph_msg_revoke()
is called while the messenger is sending message's data portion,
anything we send after that call is counted by the OSD towards the now
revoked message's data portion. The effects vary, the most common one
is the eventual hang - higher layers get stuck waiting for the reply to
the message that was sent out after ceph_msg_revoke() returned and
treated by the OSD as a bunch of data bytes. This is what Matt ran
into.
(2) Flat out zeroing con->out_kvec_bytes worth of bytes to handle kvecs
is wrong. If ceph_msg_revoke() is called before the tag is sent out or
while the messenger is sending the header, we will get a connection
reset, either due to a bad tag (0 is not a valid tag) or a bad header
CRC, which kind of defeats the purpose of revoke. Currently the kernel
client refuses to work with header CRCs disabled, but that will likely
change in the future, making this even worse.
(3) con->out_skip is not reset on connection reset, leading to one or
more spurious connection resets if we happen to get a real one between
con->out_skip is set in ceph_msg_revoke() and before it's cleared in
write_partial_skip().
Fixing (1) and (3) is trivial. The idea behind fixing (2) is to never
zero the tag or the header, i.e. send out tag+header regardless of when
ceph_msg_revoke() is called. That way the header is always correct, no
unnecessary resets are induced and revoke stands ready for disabled
CRCs. Since ceph_msg_revoke() rips out con->out_msg, introduce a new
"message out temp" and copy the header into it before sending.
Reported-by: Matt Conner <matt.conner@keepertech.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Tested-by: Matt Conner <matt.conner@keepertech.com>
Reviewed-by: Sage Weil <sage@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 103502a35c upstream.
Before this patch, a process with some permissive seccomp filter
that was applied by root without NO_NEW_PRIVS was able to add
more filters to itself without setting NO_NEW_PRIVS by setting
the new filter from a throwaway thread with NO_NEW_PRIVS.
Signed-off-by: Jann Horn <jann@thejh.net>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit fb2a24a1c6 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: 03c2299063 (cpufreq: pxa: make pxa_freqs arrays const)
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit acc1469439 upstream.
Make the divisor signed as DIV_ROUND_CLOSEST is undefined for negative
dividends when the divisor is unsigned.
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 000e094914 upstream.
Thermal hook gpio_fan_get_cur_state is only interested in knowing
the current speed index that was setup in the system, this is
already available as part of fan_data->speed_index which is always
set by set_fan_speed. Using get_fan_speed_index is useful when we
have no idea about the fan speed configuration (for example during
fan_ctrl_init).
When thermal framework invokes
gpio_fan_get_cur_state=>get_fan_speed_index via gpio_fan_get_cur_state
especially in a polled configuration for thermal governor, we
basically hog the i2c interface to the extent that other functions
fail to get any traffic out :(.
Instead, just provide the last state set in the driver - since the gpio
fan driver is responsible for the fan state immaterial of override, the
fan_data->speed_index should accurately reflect the state.
Fixes: b5cf88e46b ("(gpio-fan): Add thermal control hooks")
Reported-by: Tony Lindgren <tony@atomide.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6220f4ebd7 upstream.
Since Linux 4.0 the CPU fan speed is going up and down on Dell Studio
XPS 8000 and 8100 for unknown reasons. The 8100 was already
blacklisted in commit a4b45b25f1 ("hwmon: (dell-smm) Blacklist
Dell Studio XPS 8100"). This patch blacklists the XPS 8000.
Without further debugging on the affected machine, it is not possible
to find the problem. For more details see
https://bugzilla.kernel.org/show_bug.cgi?id=100121
Signed-off-by: Thorsten Leemhuis <linux@leemhuis.info>
Acked-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ff140fea84 upstream.
Current thermal code does not handle system sleep well because
1. the cooling device cooling state may be changed during suspend
2. the previous temperature reading becomes invalid after resumed because
it is got before system sleep
3. updating thermal zone device during suspending/resuming
is wrong because some devices may have already been suspended
or may have not been resumed.
Thus, the proper way to do this is to cancel all thermal zone
device update requirements during suspend/resume, and after all
the devices have been resumed, reset and update every registered
thermal zone devices.
This also fixes a regression introduced by:
Commit 19593a1fb1 ("ACPI / fan: convert to platform driver")
Because, with above commit applied, all the fan devices are attached
to the acpi_general_pm_domain, and they are turned on by the pm_domain
automatically after resume, without the awareness of thermal core.
Reference: https://bugzilla.kernel.org/show_bug.cgi?id=78201
Reference: https://bugzilla.kernel.org/show_bug.cgi?id=91411
Tested-by: Manuel Krause <manuelkrause@netscape.net>
Tested-by: szegad <szegadlo@poczta.onet.pl>
Tested-by: prash <prash.n.rao@gmail.com>
Tested-by: amish <ammdispose-arch@yahoo.com>
Tested-by: Matthias <morpheusxyz123@yahoo.de>
Reviewed-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit bb431ba26c upstream.
After thermal zone device registered, as we have not read any
temperature before, thus tz->temperature should not be 0,
which actually means 0C, and thermal trend is not available.
In this case, we need specially handling for the first
thermal_zone_device_update().
Both thermal core framework and step_wise governor is
enhanced to handle this. And since the step_wise governor
is the only one that uses trends, so it's the only thermal
governor that needs to be updated.
Tested-by: Manuel Krause <manuelkrause@netscape.net>
Tested-by: szegad <szegadlo@poczta.onet.pl>
Tested-by: prash <prash.n.rao@gmail.com>
Tested-by: amish <ammdispose-arch@yahoo.com>
Tested-by: Matthias <morpheusxyz123@yahoo.de>
Reviewed-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit fbbeb8632b upstream.
The current code is problematic when the QP creation and ipoib is used to
support NFS and NFS desires to do IO for paging purposes. In that case, the
GFP_KERNEL allocation in qib_qp.c causes a deadlock in tight memory
situations.
This fix adds support to create queue pair with GFP_NOIO flag for connected
mode only to cleanly fail the create queue pair in those situations.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Vinit Agnihotri <vinit.abhay.agnihotri@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ee1cdcdae5 upstream.
The commit 2895b2cad6 ("dmaengine: dw: fix cyclic transfer callbacks")
re-enabled BLOCK interrupts with regard to make cyclic transfers work. However,
this change becomes a regression for non-cyclic transfers as interrupt counters
under stress test had been grown enormously (approximately per 4-5 bytes in the
UART loop back test).
Taking into consideration above enable BLOCK interrupts if and only if channel
is programmed to perform cyclic transfer.
Fixes: 2895b2cad6 ("dmaengine: dw: fix cyclic transfer callbacks")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mans Rullgard <mans@mansr.com>
Tested-by: Mans Rullgard <mans@mansr.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 611dcadb01 upstream.
When having cyclic transfers, the channel was paused when performing
suspend but was not correctly resumed.
Signed-off-by: Songjun Wu <songjun.wu@atmel.com>
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Fixes: e1f7c9eee7 ("dmaengine: at_xdmac: creation of the atmel eXtended DMA Controller driver")
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2895b2cad6 upstream.
Cyclic transfer callbacks rely on block completion interrupts which were
disabled in commit ff7b05f29f ("dmaengine/dw_dmac: Don't handle block
interrupts"). This re-enables block interrupts so the cyclic callbacks
can work. Other transfer types are not affected as they set the INT_EN
bit only on the last block.
Fixes: ff7b05f29f ("dmaengine/dw_dmac: Don't handle block interrupts")
Signed-off-by: Mans Rullgard <mans@mansr.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit df3bb8a0e6 upstream.
Commit 61e183f830 ("dmaengine/dw_dmac: Reconfigure interrupt and
chan_cfg register on resume") moved some channel initialisation to
a new function which must be called before starting a transfer.
This updates dw_dma_cyclic_start() to use dwc_dostart() like the other
modes, thus ensuring dwc_initialize() gets called and removing some code
duplication.
Fixes: 61e183f830 ("dmaengine/dw_dmac: Reconfigure interrupt and chan_cfg register on resume")
Signed-off-by: Mans Rullgard <mans@mansr.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6697b2cf69 upstream.
ACPI 6.1 clarified that multi-interface dimms require multiple control
region entries (DCRs) per dimm. Previously we were assuming that a
control region is only present when block-data-windows are present.
This implementation was done with an eye to be compatibility with the
looser ACPI 6.0 interpretation of this table.
1/ When coalescing the memory device (MEMDEV) tables for a single dimm,
coalesce on device_handle rather than control region index.
2/ Whenever we disocver a control region with non-zero block windows
re-scan for block-data-window (BDW) entries.
We may need to revisit this if a DIMM ever implements a format interface
outside of blk or pmem, but that is not on the foreseeable horizon.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2c3033a066 upstream.
In acpiphp_enable_slot(), there is a missing unlock path
when error occurred. It needs to be unlocked before returning
an error.
Signed-off-by: Insu Yun <wuninsu@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b186b4dcb7 upstream.
The quirk to get "acpi_backlight=vendor" behavior by default on the
Dell Inspiron 5737 was added before we started doing
"acpi_backlight=native" by default on Win8 ready machines.
Since we now avoid using acpi-video as backlight driver on these machines
by default (using the native driver instead) we no longer need this quirk.
Moreover the vendor driver does not work after a suspend/resume where
as the native driver does.
This reverts commit 08a56226d8 (ACPI / video: Add Dell Inspiron 5737
to the blacklist).
Link: https://bugzilla.kernel.org/show_bug.cgi?id=111061
Reported-and-tested-by: erusan@gmail.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5b57167749 upstream.
The sw842 library code was merged in linux-4.1 and causes a very rare randconfig
failure when CONFIG_CRC32 is not set:
lib/built-in.o: In function `sw842_compress':
oid_registry.c:(.text+0x12ddc): undefined reference to `crc32_be'
lib/built-in.o: In function `sw842_decompress':
oid_registry.c:(.text+0x137e4): undefined reference to `crc32_be'
This adds an explict 'select CRC32' statement, similar to what the other users
of the crc32 code have. In practice, CRC32 is always enabled anyway because
over 100 other symbols select it.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 2da572c959 ("lib: add software 842 compression/decompression")
Acked-by: Dan Streetman <ddstreet@ieee.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a9cf8284b4 upstream.
Commit 9d99a8dda1 ("nvme: move hardware structures out of the uapi
version of nvme.h") renamed nvme.h to nvme_ioctl.h, but the uapi list
still refers to nvme.h. People trying to install the headers hit a
failure as the header no longer exists.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit bae5336f0a upstream.
If transflective backlight is supported and the brightness is zero
(lowest brightness level), the set_lcd_brightness function will activate
the transflective backlight, making the LCD appear to be turned off.
This patch fixes the issue by incrementing the brightness level, and
by doing so, avoiding the activation of the tranflective backlight.
Reported-and-tested-by: Fabian Koester <fabian.koester@bringnow.com>
Signed-off-by: Azael Avalos <coproscefalo@gmail.com>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 39d4275058 upstream.
set_power_state defaults to no displays, so we need to update
the display configuration after setting up the powerstate on the
first call. In most cases this is not an issue since ends up
getting called multiple times at any given modeset and the proper
order is achieved in the display changed handling at the top of
the function.
Reviewed-by: Christian König <christian.koenig@amd.com>
Acked-by: Jordan Lazare <Jordan.Lazare@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2b8341b3f9 upstream.
This fixes a regression introduced in Linux 4.4.
Limit the amount of time radeon_flip_work_func can
delay programming a page flip, by both limiting the
maximum amount of time per wait cycle and the maximum
number of wait cycles. Continue the flip if the limit
is exceeded, even if that may result in a visual or
timing glitch.
This is to prevent a hang of page flips, as reported
in fdo bug #93746: Disconnecting a DisplayPort display
in parallel to a kms pageflip getting queued can cause
the following hang of page flips and thereby an unusable
desktop:
1. kms pageflip ioctl() queues pageflip -> queues execution
of radeon_flip_work_func.
2. Hotunplug of display causes the driver to DPMS OFF
the unplugged display. Display engine shuts down,
scanout no longer moves, but stays at its resting
position at start line of vblank.
3. radeon_flip_work_func executes while crtc is off, and
due to the non-moving scanout position, the new flip
delay code introduced into Linux 4.4 by
commit 5b5561b366 ("drm/radeon: Fixup hw vblank counter/ts..")
enters an infinite wait loop.
4. After reconnecting the display, the pageflip continues
to hang in 3. and the display doesn't update its view
of the desktop.
This patch fixes the Linux 4.4 regression from fdo bug #93746
<https://bugs.freedesktop.org/show_bug.cgi?id=93746>
v2: Skip wait immediately if !radeon_crtc->enabled, as
suggested by Michel.
Reported-by: Bernd Steinhauser <linux@bernd-steinhauser.de>
Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Tested-by: Bernd Steinhauser <linux@bernd-steinhauser.de>
Cc: Michel Dänzer <michel.daenzer@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit bb74fc1bf3 upstream.
drm_vblank_offdelay can have three different types of values:
< 0 is to be always treated the same as dev->vblank_disable_immediate
= 0 is to be treated as "never disable vblanks"
> 0 is to be treated as disable immediate if kms driver wants it
that way via dev->vblank_disable_immediate. Otherwise it is
a disable timeout in msecs.
This got broken in Linux 3.18+ for the implementation of
drm_vblank_on. If the user specified a value of zero which should
always reenable vblank irqs in this function, a kms driver could
override the users choice by setting vblank_disable_immediate
to true. This patch fixes the regression and keeps the user in
control.
v2: Only reenable vblank if there are clients left or the user
requested to "never disable vblanks" via offdelay 0. Enabling
vblanks even in the "delayed disable" case (offdelay > 0) was
specifically added by Ville in commit cd19e52aee
("drm: Kick start vblank interrupts at drm_vblank_on()"),
but after discussion it turns out that this was done by accident.
Citing Ville: "I think it just ended up as a mess due to changing
some of the semantics of offdelay<0 vs. offdelay==0 vs.
disable_immediate during the review of the series. So yeah, given
how drm_vblank_put() works now, I'd just make this check for
offdelay==0."
Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: michel@daenzer.net
Cc: vbabka@suse.cz
Cc: ville.syrjala@linux.intel.com
Cc: daniel.vetter@ffwll.ch
Cc: dri-devel@lists.freedesktop.org
Cc: alexander.deucher@amd.com
Cc: christian.koenig@amd.com
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c61934ed9a upstream.
Changes to drm_update_vblank_count() in Linux 4.4 broke the
behaviour of the pre/post modeset functions as the new update
code doesn't deal with hw vblank counter resets inbetween calls
to drm_vblank_pre_modeset an drm_vblank_post_modeset, as it
should.
This causes mistreatment of such hw counter resets as counter
wraparound, and thereby large forward jumps of the software
vblank counter which in turn cause vblank event dispatching
and vblank waits to fail/hang --> userspace clients hang.
This symptom was reported on radeon-kms to cause a infinite
hang of KDE Plasma 5 shell's login procedure, preventing users
from logging in.
Fix this by detecting when drm_update_vblank_count() is called
inside a pre->post modeset interval. If so, clamp valid vblank
increments to the safe values 0 and 1, pretty much restoring
the update behavior of the old update code of Linux 4.3 and
earlier. Also reset the last recorded hw vblank count at call
to drm_vblank_post_modeset() to be safe against hw that after
modesetting, dpms on etc. only fires its first vblank irq after
drm_vblank_post_modeset() was already called.
Reported-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Tested-by: Vlastimil Babka <vbabka@suse.cz>
Cc: michel@daenzer.net
Cc: vbabka@suse.cz
Cc: ville.syrjala@linux.intel.com
Cc: daniel.vetter@ffwll.ch
Cc: dri-devel@lists.freedesktop.org
Cc: alexander.deucher@amd.com
Cc: christian.koenig@amd.com
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 99b8e71597 upstream.
This fixes a regression introduced by the new drm_update_vblank_count()
implementation in Linux 4.4:
Restrict the bump of the software vblank counter in drm_update_vblank_count()
to a safe maximum value of +1 whenever there is the possibility that
concurrent readers of vblank timestamps could be active at the moment,
as the current implementation of the timestamp caching and updating is
not safe against concurrent readers for calls to store_vblank() with a
bump of anything but +1. A bump != 1 would very likely return corrupted
timestamps to userspace, because the same slot in the cache could
be concurrently written by store_vblank() and read by one of those
readers in a non-atomic fashion and without the read-retry logic
detecting this collision.
Concurrent readers can exist while drm_update_vblank_count() is called
from the drm_vblank_off() or drm_vblank_on() functions or other non-vblank-
irq callers. However, all those calls are happening with the vbl_lock
locked thereby preventing a drm_vblank_get(), so the vblank refcount
can't increase while drm_update_vblank_count() is executing. Therefore
a zero vblank refcount during execution of that function signals that
is safe for arbitrary counter bumps if called from outside vblank irq,
whereas a non-zero count is not safe.
Whenever the function is called from vblank irq, we have to assume concurrent
readers could show up any time during its execution, even if the refcount
is currently zero, as vblank irqs are usually only enabled due to the
presence of readers, and because when it is called from vblank irq it
can't hold the vbl_lock to protect it from sudden bumps in vblank refcount.
Therefore also restrict bumps to +1 when the function is called from vblank
irq.
Such bumps of more than +1 can happen at other times than reenabling
vblank irqs, e.g., when regular vblank interrupts get delayed by more
than 1 frame due to long held locks, long irq off periods, realtime
preemption on RT kernels, or system management interrupts.
A better solution would be to rewrite the timestamp caching to use
full seqlocks to allow concurrent writes and reads for arbitrary
vblank counter increments.
v2: Add code comment that this is essentially a hack and should
be replaced by a full seqlock implementation for caching of
timestamps.
Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: michel@daenzer.net
Cc: vbabka@suse.cz
Cc: ville.syrjala@linux.intel.com
Cc: daniel.vetter@ffwll.ch
Cc: dri-devel@lists.freedesktop.org
Cc: alexander.deucher@amd.com
Cc: christian.koenig@amd.com
Signed-off-by: Dave Airlie <airlied@redhat.com>
commit e8235891b3 upstream.
Otherwise if a kms driver calls into drm_vblank_off() more than once
before calling drm_vblank_on() again, the redundant calls to
vblank_disable_and_save() will call drm_update_vblank_count()
while hw vblank counters and vblank timestamping are in a undefined
state during modesets, dpms off etc.
At least with the legacy drm helpers it is not unusual to
get multiple calls to drm_vblank_off and drm_vblank_on, e.g.,
half a dozen calls to drm_vblank_off and two calls to drm_vblank_on
were observed on radeon-kms during dpms-off -> dpms-on transition.
We don't no-op calls from atomic modesetting drivers, as they
should do a proper job of tracking hw state.
Fixes large jumps of the software maintained vblank counter due to
the hardware vblank counter resetting to zero during dpms off or
modeset, e.g., if radeon-kms is modified to use drm_vblank_off/on
instead of drm_vblank_pre/post_modeset().
This fixes a regression caused by the changes made to
drm_update_vblank_count() in Linux 4.4.
v2: Don't no-op on atomic modesetting drivers, per suggestion
of Daniel Vetter.
Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: michel@daenzer.net
Cc: vbabka@suse.cz
Cc: ville.syrjala@linux.intel.com
Cc: alexander.deucher@amd.com
Cc: christian.koenig@amd.com
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
