This allow us to debug how long take each SMM call and how long is system
frozen in SMM handler.
Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Some Dell machines (e.g. Dell Precision M3800) have two fans, first with
index=0 and second with index=2. So export also attributes for third fan
device with index=2.
Reported-by: Tolga Cakir <cevelnet@gmail.com>
Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Tested-by: Tolga Cakir <cevelnet@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
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 f989e55452 ("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 <cevelnet@gmail.com>
Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=112021
Cc: stable@vger.kernel.org # v4.0+, will need backport
Tested-by: Tolga Cakir <cevelnet@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
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 a4b45b25f1 ("hwmon: (dell-smm) Blacklist Dell Studio XPS 8100")
and 6220f4ebd7 ("hwmon: (dell-smm) Blacklist Dell Studio XPS 8000") were
moved to FAN_TYPE blacklist.
Reported-by: Jan C Peters <jcpeters89@gmail.com>
Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=100121
Cc: stable@vger.kernel.org # v4.0+, will need backport
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
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 <Mario_Limonciello@dell.com>
Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Cc: stable@vger.kernel.org # will need backport
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
ABI of I8K_BIOS_VERSION ioctl can return only number. But new BIOS versions
contain also other characters, which does not fit into that ABI. So in case
of non digit values return -EINVAL.
Reported-by: Mario Limonciello <Mario_Limonciello@dell.com>
Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
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>
Cc: stable@vger.kernel.org # v4.0+, will need backport
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
CPU fan speed going up and down on Dell Studio XPS 8100 for
unknown reasons. Without further debugging on the affected
machine, it is not possible to find the problem.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=100121
Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Tested-by: Jan C Peters <jcpeters89@gmail.com>
Cc: stable@vger.kernel.org # v4.0+, will need backport
[groeck: cleaned up description, comments]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
As per Documentation/hwmon/sysfs-interface, hwmon name attributes must
not include '-', so replace 'dell-smm' with 'dell_smm'.
Fixes: 039ae58503 ("hwmon: Allow to compile dell-smm-hwmon driver without /proc/i8k")
Signed-off-by: Gabriele Mazzotta <gabriele.mzt@gmail.com>
Acked-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This patch splits CONFIG_I8K compile option to SENSORS_DELL_SMM and CONFIG_I8K.
Option SENSORS_DELL_SMM is now used to enable compilation of dell-smm-hwmon
driver and old CONFIG_I8K option to enable /proc/i8k interface in driver.
So this change allows to compile dell-smm-hwmon driver without legacy /proc/i8k
interface which is needed only for old Dell Inspirion models or for userspace
i8kutils package.
For backward compatibility when CONFIG_I8K is enabled then also SENSORS_DELL_SMM
is enabled and so driver dell-smm-hwmon (with /proc/i8k) is compiled.
Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit moves i8k driver to hwmon tree under name dell-smm-hwmon which is
better name then abbreviation i8k. For backward compatibility is added macro
MODULE_ALIAS("i8k") so modprobe will load driver also old name i8k. CONFIG_I8K
compile option was not changed.
This commit also adds me as maintainer of this new dell-smm-hwmon driver and
remove Guenter Roeck from list who is implicit maintainer all hwmon drivers.
Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
