linux-toradex.git/drivers, branch v4.4.16

drm/i915: Revert DisplayPort fast link training feature

2016-07-27T16:47:40+00:00

commit 34511dce4b35685d3988d5c8b100d11a068db5bd upstream.

It has been found out that in some HW combination the DisplayPort
fast link training feature caused screen flickering. Let's revert
this feature for now until we can ensure that the feature works for
all platforms.

This is a manual revert of commits 5fa836a9d859 ("drm/i915: DP link
training optimization") and 4e96c97742f4 ("drm/i915: eDP link training
optimization").

Fixes: 5fa836a9d859 ("drm/i915: DP link training optimization")
Fixes: 4e96c97742f4 ("drm/i915: eDP link training optimization")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=91393
Reviewed-by: Jani Nikula 
Signed-off-by: Mika Kahola 
Signed-off-by: Jani Nikula 
Link: http://patchwork.freedesktop.org/patch/msgid/1466410226-19543-1-git-send-email-mika.kahola@intel.com
(cherry picked from commit 91df09d92ad82c8778ca218097bf827f154292ca)
Signed-off-by: Joakim Tjernlund 
Signed-off-by: Greg Kroah-Hartman

crypto: qat - make qat_asym_algs.o depend on asn1 headers

2016-07-27T16:47:40+00:00

commit 81dc0365cfa7bc7c08a0e44d9ee04964df782e19 upstream.

Parallel build can sporadically fail because asn1 headers may
not be built yet by the time qat_asym_algs.o is compiled:
  drivers/crypto/qat/qat_common/qat_asym_algs.c:55:32: fatal error: qat_rsapubkey-asn1.h: No such file or directory
   #include "qat_rsapubkey-asn1.h"

Signed-off-by: Jan Stancek 
Signed-off-by: Herbert Xu 
Signed-off-by: Greg Kroah-Hartman

xen/acpi: allow xen-acpi-processor driver to load on Xen 4.7

2016-07-27T16:47:39+00:00

commit 6f2d9d99213514360034c6d52d2c3919290b3504 upstream.

As of Xen 4.7 PV CPUID doesn't expose either of CPUID[1].ECX[7] and
CPUID[0x80000007].EDX[7] anymore, causing the driver to fail to load on
both Intel and AMD systems. Doing any kind of hardware capability
checks in the driver as a prerequisite was wrong anyway: With the
hypervisor being in charge, all such checking should be done by it. If
ACPI data gets uploaded despite some missing capability, the hypervisor
is free to ignore part or all of that data.

Ditch the entire check_prereq() function, and do the only valid check
(xen_initial_domain()) in the caller in its place.

Signed-off-by: Jan Beulich 
Signed-off-by: David Vrabel 
Signed-off-by: Greg Kroah-Hartman

53c700: fix BUG on untagged commands

2016-07-27T16:47:39+00:00

commit 8beb330044d0d1878c7b92290e91c0b889e92633 upstream.

The untagged command case in the 53c700 driver has been broken since
host wide tags were enabled because the replaced scsi_find_tag()
function had a special case for the tag value SCSI_NO_TAG to retrieve
sdev->current_cmnd.  The replacement function scsi_host_find_tag() has
no such special case and returns NULL causing untagged commands to
trigger a BUG() in the driver.  Inspection shows that the 53c700 is the
only driver using this SCSI_NO_TAG case, so a local fix in the driver
suffices to fix this problem globally.

Fixes: 64d513ac31b - "scsi: use host wide tags by default"
Reported-by: Helge Deller 
Tested-by: Helge Deller 
Signed-off-by: James Bottomley 
Reviewed-by: Johannes Thumshirn 
Reviewed-by: Ewan D. Milne 
Acked-by: Christoph Hellwig 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Greg Kroah-Hartman

scsi: fix race between simultaneous decrements of ->host_failed

2016-07-27T16:47:39+00:00

commit 72d8c36ec364c82bf1bf0c64dfa1041cfaf139f7 upstream.

sas_ata_strategy_handler() adds the works of the ata error handler to
system_unbound_wq. This workqueue asynchronously runs work items, so the
ata error handler will be performed concurrently on different CPUs. In
this case, ->host_failed will be decreased simultaneously in
scsi_eh_finish_cmd() on different CPUs, and become abnormal.

It will lead to permanently inequality between ->host_failed and
->host_busy, and scsi error handler thread won't start running. IO
errors after that won't be handled.

Since all scmds must have been handled in the strategy handler, just
remove the decrement in scsi_eh_finish_cmd() and zero ->host_busy after
the strategy handler to fix this race.

Fixes: 50824d6c5657 ("[SCSI] libsas: async ata-eh")
Signed-off-by: Wei Fang 
Reviewed-by: James Bottomley 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Greg Kroah-Hartman

hwmon: (dell-smm) Cache fan_type() calls and change fan detection

2016-07-27T16:47:37+00:00

commit 5ce91714b0d8c0a3ff9b858966721f508351cf4c upstream.

On more Dell machines (e.g. Dell Precision M3800) fan_type() call is too
expensive (CPU is too long in SMM mode) and cause kernel to hang. This is
bug in Dell SMM or BIOS.

This patch caches type for each fan (as it should not change) and changes
the way how fan presense is detected. First it try function fan_status()
as was before commit f989e55452c7 ("i8k: Add support for fan labels"). And
if that fails fallback to fan_type(). *_status() functions can fail in case
fan is not currently accessible (e.g. present on GPU which is currently
turned off).

Reported-by: Tolga Cakir 
Signed-off-by: Pali Rohár 
Link: https://bugzilla.kernel.org/show_bug.cgi?id=112021
Tested-by: Tolga Cakir 
Signed-off-by: Guenter Roeck 
Signed-off-by: Greg Kroah-Hartman

hwmon: (dell-smm) Disallow fan_type() calls on broken machines

2016-07-27T16:47:37+00:00

commit 2744d2fde00dc8bcc3679eb72c81a63058e90faa upstream.

Some Dell machines have especially broken SMM or BIOS which cause that once
fan_type() is called then CPU fan speed going randomly up and down. And for
fixing this behaviour reboot is required.

So this patch creates fan_type blacklist of affected Dell machines and
disallow fan_type() call on them to prevent that erratic behaviour.

Old blacklist which disabled loading driver on some machines added in
commits a4b45b25f18d ("hwmon: (dell-smm) Blacklist Dell Studio XPS 8100")
and 6220f4ebd7b4 ("hwmon: (dell-smm) Blacklist Dell Studio XPS 8000") were
moved to FAN_TYPE blacklist.

Reported-by: Jan C Peters 
Signed-off-by: Pali Rohár 
Link: https://bugzilla.kernel.org/show_bug.cgi?id=100121
Signed-off-by: Guenter Roeck 
Signed-off-by: Greg Kroah-Hartman

hwmon: (dell-smm) Restrict fan control and serial number to CAP_SYS_ADMIN by default

2016-07-27T16:47:37+00:00

commit 7613663cc186f8f3c50279390ddc60286758001c upstream.

For security reasons ordinary user must not be able to control fan speed
via /proc/i8k by default. Some malicious software running under "nobody"
user could be able to turn fan off and cause HW problems. So this patch
changes default value of "restricted" parameter to 1.

Also restrict reading of DMI_PRODUCT_SERIAL from /proc/i8k via "restricted"
parameter. It is because non root user cannot read DMI_PRODUCT_SERIAL from
sysfs file /sys/class/dmi/id/product_serial.

Old non secure behaviour of file /proc/i8k can be achieved by loading this
module with "restricted" parameter set to 0.

Note that this patch has effects only for kernels compiled with CONFIG_I8K
and only for file /proc/i8k. Hwmon interface provided by this driver was
not changed and root access for setting fan speed was needed also before.

Reported-by: Mario Limonciello 
Signed-off-by: Pali Rohár 
Signed-off-by: Guenter Roeck 
Signed-off-by: Greg Kroah-Hartman

tty/vt/keyboard: fix OOB access in do_compute_shiftstate()

2016-07-27T16:47:37+00:00

commit 510cccb5b0c8868a2b302a0ab524da7912da648b upstream.

The size of individual keymap in drivers/tty/vt/keyboard.c is NR_KEYS,
which is currently 256, whereas number of keys/buttons in input device (and
therefor in key_down) is much larger - KEY_CNT - 768, and that can cause
out-of-bound access when we do

	sym = U(key_maps[0][k]);

with large 'k'.

To fix it we should not attempt iterating beyond smaller of NR_KEYS and
KEY_CNT.

Also while at it let's switch to for_each_set_bit() instead of open-coding
it.

Reported-by: Sasha Levin 
Reviewed-by: Guenter Roeck 
Signed-off-by: Dmitry Torokhov 
Signed-off-by: Greg Kroah-Hartman

tty: vt: Fix soft lockup in fbcon cursor blink timer.

2016-07-27T16:47:37+00:00

commit 1b45996d2ebf9680ccd0db875fc668aa025f40fd upstream.

We are getting somewhat random soft lockups with this signature:

[   86.992215] [] el1_irq+0xa0/0x10c
[   86.997082] [] cursor_timer_handler+0x30/0x54
[   87.002991] [] call_timer_fn+0x54/0x1a8
[   87.008378] [] run_timer_softirq+0x1c4/0x2bc
[   87.014200] [] __do_softirq+0x114/0x344
[   87.019590] [] irq_exit+0x74/0x98
[   87.024458] [] __handle_domain_irq+0x98/0xfc
[   87.030278] [] gic_handle_irq+0x94/0x190

This is caused by the vt visual_init() function calling into
fbcon_init() with a vc_cur_blink_ms value of zero.  This is a
transient condition, as it is later set to a non-zero value.  But, if
the timer happens to expire while the blink rate is zero, it goes into
an endless loop, and we get soft lockup.

The fix is to initialize vc_cur_blink_ms before calling the con_init()
function.

Signed-off-by: David Daney 
Acked-by: Pavel Machek 
Tested-by: Ming Lei 
Acked-by: Scot Doyle 
Tested-by: Henrique de Moraes Holschuh 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Greg Kroah-Hartman