linux/drivers/char
Stephen Boyd 03a3bb7ae6 hwrng: core - Freeze khwrng thread during suspend
The hwrng_fill() function can run while devices are suspending and
resuming. If the hwrng is behind a bus such as i2c or SPI and that bus
is suspended, the hwrng may hang the bus while attempting to add some
randomness. It's been observed on ChromeOS devices with suspend-to-idle
(s2idle) and an i2c based hwrng that this kthread may run and ask the
hwrng device for randomness before the i2c bus has been resumed.

Let's make this kthread freezable so that we don't try to touch the
hwrng during suspend/resume. This ensures that we can't cause the hwrng
backing driver to get into a bad state because the device is guaranteed
to be resumed before the hwrng kthread is thawed.

Cc: Andrey Pronin <apronin@chromium.org>
Cc: Duncan Laurie <dlaurie@chromium.org>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guenter Roeck <groeck@chromium.org>
Cc: Alexander Steffen <Alexander.Steffen@infineon.com>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-08-15 21:52:13 +10:00
..
agp Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-07-08 10:39:56 -07:00
hw_random hwrng: core - Freeze khwrng thread during suspend 2019-08-15 21:52:13 +10:00
ipmi Some small fixes for various things, nothing huge, mostly found 2019-07-13 15:07:02 -07:00
mwave treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
pcmcia treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 18 2019-05-21 11:28:46 +02:00
tpm tpm: Don't duplicate events from the final event log in the TCG2 log 2019-06-24 23:57:50 +03:00
xilinx_hwicap treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
xillybus treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 402 2019-06-05 17:37:13 +02:00
adi.c char: sparc64: Add privileged ADI driver 2018-06-05 11:24:55 -07:00
apm-emulation.c treewide: Add SPDX license identifier for more missed files 2019-05-21 10:50:45 +02:00
applicom.c treewide: Add SPDX license identifier for more missed files 2019-05-21 10:50:45 +02:00
applicom.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
bsr.c Merge 5.2-rc4 into char-misc-next 2019-06-09 09:11:21 +02:00
ds1620.c treewide: Add SPDX license identifier for more missed files 2019-05-21 10:50:45 +02:00
dsp56k.c vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
dtlk.c treewide: Add SPDX license identifier for more missed files 2019-05-21 10:50:45 +02:00
efirtc.c treewide: Add SPDX license identifier for more missed files 2019-05-21 10:50:45 +02:00
hangcheck-timer.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 405 2019-06-05 17:37:13 +02:00
hpet.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
Kconfig docs: admin-guide: add a series of orphaned documents 2019-07-15 11:03:02 -03:00
lp.c treewide: Add SPDX license identifier for more missed files 2019-05-21 10:50:45 +02:00
Makefile char/generic_nvram: Remove as unused 2019-01-22 10:21:45 +01:00
mbcs.c mbcs: add .owner to mbcs struct file_operations 2019-01-22 14:56:00 +01:00
mbcs.h
mem.c Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
misc.c char: misc: Move EXPORT_SYMBOL immediately next to the functions/varibles 2019-05-24 18:00:41 +02:00
mspec.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 206 2019-05-30 11:29:53 -07:00
nsc_gpio.c treewide: Add SPDX license identifier for more missed files 2019-05-21 10:50:45 +02:00
nvram.c treewide: Add SPDX license identifier for more missed files 2019-05-21 10:50:45 +02:00
nwbutton.c treewide: Add SPDX license identifier for more missed files 2019-05-21 10:50:45 +02:00
nwbutton.h treewide: Switch DEFINE_TIMER callbacks to struct timer_list * 2017-11-21 15:57:05 -08:00
nwflash.c treewide: Add SPDX license identifier for more missed files 2019-05-21 10:50:45 +02:00
pc8736x_gpio.c treewide: Add SPDX license identifier for more missed files 2019-05-21 10:50:45 +02:00
powernv-op-panel.c treewide: Add SPDX license identifier for more missed files 2019-05-21 10:50:45 +02:00
ppdev.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
ps3flash.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 164 2019-05-30 11:26:38 -07:00
random.c random: fix soft lockup when trying to read from an uninitialized blocking pool 2019-05-26 00:11:49 -04:00
raw.c treewide: Add SPDX license identifier for more missed files 2019-05-21 10:50:45 +02:00
rtc.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
scx200_gpio.c treewide: Add SPDX license identifier for more missed files 2019-05-21 10:50:45 +02:00
snsc_event.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/signal.h> 2017-03-02 08:42:29 +01:00
snsc.c vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
snsc.h
sonypi.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 61 2019-05-24 17:36:45 +02:00
tb0219.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
tlclk.c tlclk: clean an indentation issue, remove extraneous tabs 2018-11-11 12:58:27 -08:00
toshiba.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 129 2019-05-30 11:25:14 -07:00
ttyprintk.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 402 2019-06-05 17:37:13 +02:00
uv_mmtimer.c
virtio_console.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00