Revision 7ff57e98fb78ad94edafbdc7435f2d745e9e6bb5 authored by Fabio M. De Francesco on 23 February 2022, 10:02:52 UTC, committed by Jakub Kicinski on 24 February 2022, 17:09:33 UTC
smc_pnetid_by_table_ib() uses read_lock() and then it calls smc_pnet_apply_ib()
which, in turn, calls mutex_lock(&smc_ib_devices.mutex).
read_lock() disables preemption. Therefore, the code acquires a mutex while in
atomic context and it leads to a SAC bug.
Fix this bug by replacing the rwlock with a mutex.
Reported-and-tested-by: syzbot+4f322a6d84e991c38775@syzkaller.appspotmail.com
Fixes: 64e28b52c7a6 ("net/smc: add pnet table namespace support")
Confirmed-by: Tony Lu <tonylu@linux.alibaba.com>
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Acked-by: Karsten Graul <kgraul@linux.ibm.com>
Link: https://lore.kernel.org/r/20220223100252.22562-1-fmdefrancesco@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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emc6w201.rst
Kernel driver emc6w201
======================
Supported chips:
* SMSC EMC6W201
Prefix: 'emc6w201'
Addresses scanned: I2C 0x2c, 0x2d, 0x2e
Datasheet: Not public
Author: Jean Delvare <jdelvare@suse.de>
Description
-----------
From the datasheet:
"The EMC6W201 is an environmental monitoring device with automatic fan
control capability and enhanced system acoustics for noise suppression.
This ACPI compliant device provides hardware monitoring for up to six
voltages (including its own VCC) and five external thermal sensors,
measures the speed of up to five fans, and controls the speed of
multiple DC fans using three Pulse Width Modulator (PWM) outputs. Note
that it is possible to control more than three fans by connecting two
fans to one PWM output. The EMC6W201 will be available in a 36-pin
QFN package."
The device is functionally close to the EMC6D100 series, but is
register-incompatible.
The driver currently only supports the monitoring of the voltages,
temperatures and fan speeds. Limits can be changed. Alarms are not
supported, and neither is fan speed control.
Known Systems With EMC6W201
---------------------------
The EMC6W201 is a rare device, only found on a few systems, made in
2005 and 2006. Known systems with this device:
* Dell Precision 670 workstation
* Gigabyte 2CEWH mainboard
Computing file changes ...
