Rajat Jain
c4f2f5e498
PCI: pciehp: Ensure very fast hotplug events are also processed ...
Today, this is how all the hotplug and unplug events work:
Hotplug / Removal needs to be done
=> Set slot->state (protected by slot->lock) to either
POWERON_STATE (for enabling) or POWEROFF_STATE (for disabling).
=> Submit the work item for pciehp_power_thread() to slot->wq.
Problem:
There is a problem if the hotplug events can happen fast enough that
they do not give SW enough time to add or remove the new devices.
=> Assume: Event for unplug comes (e.g. surprise removal). But
before the pciehp_power_thread() work item was executed, the
card was replaced by another card, causing surprise hotplug event.
=> What goes wrong:
=> The hot-removal event sets slot->state to POWEROFF_STATE, and
schedules the pciehp_power_thread().
=> The hot-add event sets slot->state to POWERON_STATE, and
schedules the pciehp_power_thread().
=> Now the pciehp_power_thread() is scheduled twice, and on both
occasions it will find POWERON_STATE and will try to add the
devices on the slot, and will fail complaining that the devices
already exist.
=> Why this is a problem: If the device was replaced between the hot
removal and hot-add, then we should unload the old driver and
reload the new one. This does not happen today. The kernel or the
driver is not even aware that the device was replaced.
The problem is that the pciehp_power_thread() only looks at the
slot->state which would only contain the *latest* state - not
the actual event (add / remove) that was the intent of the IRQ
handler who submitted the work.
What this patch does:
=> Hotplug events pass on an actual request (for addition or removal)
to pciehp_power_thread() which is local to that work item
submission.
=> pciehp_power_thread() does not need to look at slote->state and
hence no locks needed in that.
=> Essentially this results in all the hotplug and unplug events
"replayed" by pciehp_power_thread().
Signed-off-by: Rajat Jain <[email protected] >
Signed-off-by: Rajat Jain <[email protected] >
Signed-off-by: Guenter Roeck <[email protected] >
Signed-off-by: Bjorn Helgaas <[email protected] >
2014-02-11 16:13:01 -07:00
Merge branches 'acpi-processor', 'acpi-hotplug', 'acpi-init', 'acpi-pm' and 'acpica'
2014-01-29 11:47:18 +01:00
ACPI and power management updates for 3.14-rc1
2014-01-24 15:51:02 -08:00
regmap: Updates for v3.14
2014-01-25 13:18:00 -08:00
Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
2014-01-30 17:20:32 -08:00
Bug-fixes:
2014-01-31 08:38:18 -08:00
drivers: bus: fix CCI driver kcalloc call parameters swap
2014-01-31 15:15:13 -08:00
Merge branch 'for-3.14/drivers' of git://git.kernel.dk/linux-block
2014-01-30 11:40:10 -08:00
ipmi: Add missing rv in ipmi_parisc_probe()
2014-01-30 10:02:54 -08:00
The second half of the clock framework pull requeust for 3.14 is
2014-01-28 18:44:53 -08:00
clocksource: kona: Add basic use of external clock
2014-01-31 21:04:01 -08:00
ACPI and power management fixes and cleanups for 3.14-rc1
2014-01-31 09:23:52 -08:00
powerpc/powernv/cpuidle: Back-end cpuidle driver for powernv platform.
2014-01-29 17:02:24 +11:00
ARM: driver updates for 3.14
2014-01-23 18:49:36 -08:00
Merge branches 'pm-cpufreq' and 'pm-devfreq'
2014-01-29 11:48:23 +01:00
Merge branch 'for-linus' of git://git.infradead.org/users/vkoul/slave-dma
2014-01-29 20:27:23 -08:00
firmware/google: drop 'select EFI' to avoid recursive dependency
2014-01-27 21:02:40 -08:00
ARM: driver updates for 3.14
2014-01-23 18:49:36 -08:00
Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux
2014-01-29 20:49:12 -08:00
Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
2014-01-31 09:31:14 -08:00
hyperv: Add support for physically discontinuous receive buffer
2014-01-27 16:40:45 -08:00
hwmon: Fix SENSORS_TMP102 dependencies to eliminate build errors
2014-02-02 17:59:07 +01:00
Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
2014-01-29 19:56:20 -08:00
drivers: ide: Include appropriate header file in ide-pio-blacklist.c
2014-01-28 23:35:09 -08:00
ACPI and power management updates for 3.14-rc1
2014-01-24 15:51:02 -08:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
2014-01-22 21:21:55 -08:00
Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
2014-01-31 15:31:23 -08:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
2014-01-24 17:17:30 -08:00
IOMMU Updates for Linux v3.14
2014-01-29 20:00:13 -08:00
mvebu fixes for v3.13 (incremental #2 )
2014-01-31 14:59:28 -08:00
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
2014-01-25 11:17:34 -08:00
Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds
2014-01-28 18:53:01 -08:00
Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
2014-01-27 21:11:26 -08:00
drivers/mailbox/omap: make mbox->irq signed for error handling
2014-01-23 16:36:53 -08:00
Merge branch 'for-3.14/drivers' of git://git.kernel.dk/linux-block
2014-01-30 11:40:10 -08:00
Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
2014-01-31 09:31:14 -08:00
drivers/memstick/host/rtsx_pci_ms.c: fix ms card data transfer bug
2014-01-23 16:37:04 -08:00
Merge branch 'for-3.14/core' of git://git.kernel.dk/linux-block
2014-01-30 11:19:05 -08:00
regulator: Updates for v3.14
2014-01-25 13:19:10 -08:00
Merge branch 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging
2014-01-29 18:56:27 -08:00
MMC highlights for 3.14:
2014-01-26 11:00:41 -08:00
* Improve the NOR erasure quirk - now it tries to do as little writes as
2014-01-30 20:04:09 -08:00
Merge branch 'akpm' (patches from Andrew Morton)
2014-01-30 18:44:44 -08:00
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
2014-01-25 11:17:34 -08:00
PCI: pciehp: Ensure very fast hotplug events are also processed
2014-02-11 16:13:01 -07:00
PCI changes for the v3.14 merge window:
2014-01-22 16:39:28 -08:00
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
2014-01-25 11:17:34 -08:00
ARM: SoC DT updates for 3.14
2014-01-23 18:45:38 -08:00
platform/chrome: Cleanups and improvements
2014-01-29 20:06:01 -08:00
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
2014-01-25 11:17:34 -08:00
pwm: Changes for v3.14-rc1
2014-01-27 08:15:51 -08:00
regulator: Updates for v3.14
2014-01-25 13:19:10 -08:00
Merge branch 'akpm' (incoming from Andrew)
2014-01-23 19:11:50 -08:00
Second batch of KVM updates. Some minor x86 fixes,
2014-01-31 08:37:32 -08:00
sparc: delete non-required instances of include <linux/init.h>
2014-01-28 23:38:23 -08:00
Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
2014-01-31 15:31:23 -08:00
Merge remote-tracking branch 'agust/next' into next
2014-01-29 16:53:55 +11:00
Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
2014-01-30 17:20:32 -08:00
Staging wireless driver for 3.14-rc1
2014-02-01 10:29:59 -08:00
Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
2014-01-31 15:31:23 -08:00
Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux
2014-01-24 17:13:49 -08:00
Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
2014-01-30 17:20:32 -08:00
Merge remote-tracking branch 'agust/next' into next
2014-01-29 16:53:55 +11:00
Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
2014-01-27 21:11:26 -08:00
Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
2014-01-31 15:31:23 -08:00
parisc/sti_console: prefer Linux fonts over built-in ROM fonts
2014-02-02 20:56:47 +01:00
A few simple fixes. Quiet cycle.
2014-01-22 22:24:35 -08:00
drivers/vlynq/vlynq.c: fix another resource size off by 1 error
2014-01-23 16:36:55 -08:00
drivers/w1/masters/w1-gpio.c: add strong pullup emulation
2014-01-23 16:37:04 -08:00
watchdog: w83627hf_wdt: Reset watchdog trigger during initialization
2014-01-28 21:35:40 +01:00
Bug-fixes:
2014-01-31 08:38:18 -08:00
c4f2f5e498