linux_dsm_epyc7002/drivers
Dave Airlie ec5da7f8dc fbcon: fix race condition between console lock and cursor timer
So we've had a fair few reports of fbcon handover breakage between
efi/vesafb and i915 surface recently, so I dedicated a couple of
days to finding the problem.

Essentially the last thing we saw was the conflicting framebuffer
message and that was all.

So after much tracing with direct netconsole writes (printks
under console_lock not so useful), I think I found the race.

  Thread A (driver load)    Thread B (timer thread)
    unbind_con_driver ->              |
    bind_con_driver ->                |
    vc->vc_sw->con_deinit ->          |
    fbcon_deinit ->                   |
    console_lock()                    |
        |                             |
        |                       fbcon_flashcursor timer fires
        |                       console_lock() <- blocked for A
        |
        |
  fbcon_del_cursor_timer ->
    del_timer_sync
    (BOOM)

Of course because all of this is under the console lock,
we never see anything, also since we also just unbound the active
console guess what we never see anything.

Hopefully this fixes the problem for anyone seeing vesafb->kms
driver handoff.

Signed-off-by: David Airlie <airlied@redhat.com>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: stable@vger.kernel.org
Tested-by: Josh Boyer <jwboyer@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-21 09:08:50 -07:00
..
accessibility
acpi Power management fixes for 3.6-rc2 2012-08-12 21:34:09 +03:00
amba Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm 2012-07-27 15:14:26 -07:00
ata ARM: arm-soc Marvell Orion device-tree updates 2012-08-02 11:50:24 -07:00
atm drivers/atm/iphase.c: fix error return code 2012-08-06 13:29:57 -07:00
auxdisplay
base dmesg fix for 3.6-rc3 2012-08-20 13:13:47 -07:00
bcma bcma: BCM43228 support 2012-08-02 13:51:46 -04:00
block drbd: nuke pdflush from comments 2012-08-04 12:15:39 +04:00
bluetooth
cdrom
char Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux 2012-08-14 07:52:41 +03:00
clk clk: validate pointer in __clk_disable() 2012-07-30 17:25:13 -07:00
clocksource arm-soc: new SoC support 2012-07-23 16:31:31 -07:00
connector
cpufreq drivers/cpufreq/pcc-cpufreq.c: fix error return code 2012-08-08 20:49:25 +02:00
cpuidle cpuidle: Prevent null pointer dereference in cpuidle_coupled_cpu_notify 2012-08-17 19:37:08 +02:00
crypto This patch series contains a major revamp of how we collect entropy 2012-07-31 19:07:42 -07:00
dca
devfreq
dio
dma dma: tegra: enable/disable dma clock 2012-08-13 10:15:22 +05:30
edac Merge branch 'devel' 2012-07-29 21:11:05 -03:00
eisa
extcon extcon: extcon_gpio: Replace gpio_request_one by devm_gpio_request_one 2012-08-16 10:29:08 -07:00
firewire - Small fixes and optimizations. 2012-07-30 09:32:39 -07:00
firmware This patch series contains a major revamp of how we collect entropy 2012-07-31 19:07:42 -07:00
gpio GPIO: gpio-pxa: fix building without CONFIG_OF 2012-08-14 07:50:36 +03:00
gpu More USB patches for 3.6-rc3 2012-08-20 13:14:22 -07:00
hid Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media 2012-07-31 18:47:44 -07:00
hsi
hv This patch series contains a major revamp of how we collect entropy 2012-07-31 19:07:42 -07:00
hwmon sections: Fix section conflicts in drivers/hwmon 2012-08-18 16:17:43 -07:00
hwspinlock
i2c This patch series contains a major revamp of how we collect entropy 2012-07-31 19:07:42 -07:00
ide
idle intel_idle: Check cpu_idle_get_driver() for NULL before dereferencing it. 2012-08-17 19:37:14 +02:00
ieee802154
iio iio: lm3533-als: Fix build warnings 2012-08-16 20:24:38 +01:00
infiniband Merge branches 'cma', 'ipoib', 'misc', 'mlx4', 'ocrdma', 'qib' and 'srp' into for-next 2012-08-16 09:38:39 -07:00
input Input: eeti_ts: pass gpio value instead of IRQ 2012-08-09 15:16:41 +02:00
iommu iommu/amd: Fix wrong check for ARRAY_SIZE() 2012-08-10 11:34:08 +02:00
isdn mISDN: Bugfix for layer2 fixed TEI mode 2012-08-06 13:22:50 -07:00
leds leds: renesas: fix error handling 2012-08-13 14:34:02 +08:00
lguest
macintosh
md md/raid10: fix problem with on-stack allocation of r10bio structure. 2012-08-18 09:51:42 +10:00
media USB: spca506: remove __devinit* from the struct usb_device_id table 2012-08-17 17:50:44 -07:00
memory
memstick
message drivers/message/i2o/i2o_config.c: bound allocation 2012-07-30 17:25:17 -07:00
mfd More USB patches for 3.6-rc3 2012-08-20 13:14:22 -07:00
misc ti-st: Fix check for pdata->chip_awake function pointer 2012-08-16 12:32:34 -07:00
mmc Merge branch 'dmaengine' of git://git.linaro.org/people/rmk/linux-arm 2012-08-01 16:41:07 -07:00
mtd arm-soc: bug fixes for v3.6-rc2 2012-08-12 21:31:44 +03:00
net More USB patches for 3.6-rc3 2012-08-20 13:14:22 -07:00
nfc
nubus
of Devicetree updates for 3.6 2012-07-24 14:07:22 -07:00
oprofile
parisc PCI changes for the 3.6 merge window: 2012-07-24 16:17:07 -07:00
parport
pci PCI: EHCI: Fix crash during hibernation on ASUS computers 2012-08-15 11:51:19 -06:00
pcmcia Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm 2012-07-27 15:14:26 -07:00
pinctrl drivers/pinctrl/pinctrl-nomadik.c: drop devm_kfree of devm_kzalloc'd data 2012-08-07 14:34:12 +02:00
platform ideapad: add Lenovo IdeaPad Z570 support (part 3) 2012-08-20 12:44:41 -04:00
pnp
power Merge branch 'for-linus-3.6' of git://dev.laptop.org/users/dilinger/linux-olpc 2012-08-02 11:52:39 -07:00
pps pps: return PTR_ERR on error in device_create 2012-07-30 17:25:21 -07:00
ps3
ptp
pwm pwm: pwm-tiehrpwm: PWM driver support for EHRPWM 2012-07-26 07:45:20 +02:00
rapidio
regulator regulator: twl-regulator: fix up VINTANA1/VINTANA2 2012-08-15 17:19:01 +01:00
remoteproc A batch of remoteproc patches for 3.6: 2012-07-26 16:19:08 -07:00
rpmsg A batch of remoteproc patches for 3.6: 2012-07-26 16:19:08 -07:00
rtc RTC: Avoid races between RTC alarm wakeup and suspend. 2012-08-08 20:49:16 +02:00
s390 s390/sclp_sdias: Add missing break and "fall through" 2012-08-08 07:32:55 -07:00
sbus
scsi Merge branch 'for-3.6/core' of git://git.kernel.dk/linux-block 2012-08-01 09:02:41 -07:00
sfi
sh sh: intc: Handle domain association for sparseirq pre-allocated vectors. 2012-08-09 13:21:05 +09:00
sn
spi spi: Updates for 3.6 2012-08-20 13:05:27 -07:00
ssb
staging More USB patches for 3.6-rc3 2012-08-20 13:14:22 -07:00
target Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-08-01 10:26:23 -07:00
tc
thermal The tag contains just a few battery-related changes for v3.6. It's is 2012-07-31 18:08:25 -07:00
tty pmac_zilog,kdb: Fix console poll hook to return instead of loop 2012-08-16 12:20:20 -07:00
uio
usb More USB patches for 3.6-rc3 2012-08-20 13:14:22 -07:00
uwb
vfio vfio: Add PCI device driver 2012-07-31 08:16:24 -06:00
vhost tcm_vhost: Initial merge for vhost level target fabric driver 2012-07-29 13:49:10 -07:00
video fbcon: fix race condition between console lock and cursor timer 2012-08-21 09:08:50 -07:00
virt
virtio [SCSI] virtio-scsi: Add vdrv->scan for post VIRTIO_CONFIG_S_DRIVER_OK LUN scanning 2012-07-20 08:59:03 +01:00
vlynq
vme VME: Prevent D16 cycles being split into 8-bit blocks 2012-07-19 15:39:39 -07:00
w1 1-Wire: Add support for the maxim ds1825 temperature sensor 2012-08-16 12:33:59 -07:00
watchdog ARM: arm-soc Marvell Orion device-tree updates 2012-08-02 11:50:24 -07:00
xen PCI changes for the 3.6 merge window: 2012-07-24 16:17:07 -07:00
zorro
Kconfig vfio: VFIO core 2012-07-31 08:16:22 -06:00
Makefile vfio: VFIO core 2012-07-31 08:16:22 -06:00