]> bbs.cooldavid.org Git - net-next-2.6.git/commit
ACPI / ACPICA: Fix reference counting problems with GPE handlers
authorRafael J. Wysocki <rjw@sisk.pl>
Tue, 3 Aug 2010 21:55:14 +0000 (23:55 +0200)
committerLen Brown <len.brown@intel.com>
Sat, 7 Aug 2010 14:30:12 +0000 (10:30 -0400)
commit28f4f8a9def2b1f3a6066bae791c77043ec49524
tree179cb5f8b64540e6f8e4440f46b2e930731a7fc3
parenta0d468718b9049f7396d101075a129a2d683ad66
ACPI / ACPICA: Fix reference counting problems with GPE handlers

If a handler is installed for a GPE associated with an AML method and
such that it cannot wake up the system from sleep states, the GPE
remains enabled after the handler has been installed, although it
should be disabled in that case to avoid spurious execution of the
handler.

Fix this issue by making acpi_install_gpe_handler() disable GPEs
that were previously associated with AML methods and cannot wake up
the system from sleep states.

Analogously, make acpi_remove_gpe_handler() enable the GPEs that
are associated with AML methods after their handlers have been
removed and cannot wake up the system from sleep states.  In addition
to that, fix a code ordering issue in acpi_remove_gpe_handler() that
renders the locking ineffective (ACPI_MTX_EVENTS is released
temporarily in the middle of the routine to wait for the completion
of events already in progress).

For this purpose introduce acpi_raw_disable_gpe() and
acpi_raw_enable_gpe() to be called with acpi_gbl_gpe_lock held
and rework acpi_disable_gpe() and acpi_enable_gpe(), respectively, to
use them.  Also rework acpi_gpe_can_wake() to use
acpi_raw_disable_gpe() instead of calling acpi_disable_gpe() after
releasing the lock to avoid the possible theoretical race with
acpi_install_gpe_handler().

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: "Moore, Robert" <robert.moore@intel.com>
Cc: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
drivers/acpi/acpica/acevents.h
drivers/acpi/acpica/aclocal.h
drivers/acpi/acpica/evgpe.c
drivers/acpi/acpica/evxface.c
drivers/acpi/acpica/evxfevnt.c