linux/include
Rafael J. Wysocki 0294112ee3 ACPI / PNP: Reserve ACPI resources at the fs_initcall_sync stage
This effectively reverts the following three commits:

 7bc10388cc ACPI / resources: free memory on error in add_region_before()
 0f1b414d19 ACPI / PNP: Avoid conflicting resource reservations
 b9a5e5e18f ACPI / init: Fix the ordering of acpi_reserve_resources()

(commit b9a5e5e18f introduced regressions some of which, but not
all, were addressed by commit 0f1b414d19 and commit 7bc10388cc
was a fixup on top of the latter) and causes ACPI fixed hardware
resources to be reserved at the fs_initcall_sync stage of system
initialization.

The story is as follows.  First, a boot regression was reported due
to an apparent resource reservation ordering change after a commit
that shouldn't lead to such changes.  Investigation led to the
conclusion that the problem happened because acpi_reserve_resources()
was executed at the device_initcall() stage of system initialization
which wasn't strictly ordered with respect to driver initialization
(and with respect to the initialization of the pcieport driver in
particular), so a random change causing the device initcalls to be
run in a different order might break things.

The response to that was to attempt to run acpi_reserve_resources()
as soon as we knew that ACPI would be in use (commit b9a5e5e18f).
However, that turned out to be too early, because it caused resource
reservations made by the PNP system driver to fail on at least one
system and that failure was addressed by commit 0f1b414d19.

That fix still turned out to be insufficient, though, because
calling acpi_reserve_resources() before the fs_initcall stage of
system initialization caused a boot regression to happen on the
eCAFE EC-800-H20G/S netbook.  That meant that we only could call
acpi_reserve_resources() at the fs_initcall initialization stage
or later, but then we might just as well call it after the PNP
initalization in which case commit 0f1b414d19 wouldn't be
necessary any more.

For this reason, the changes made by commit 0f1b414d19 are reverted
(along with a memory leak fixup on top of that commit), the changes
made by commit b9a5e5e18f that went too far are reverted too and
acpi_reserve_resources() is changed into fs_initcall_sync, which
will cause it to be executed after the PNP subsystem initialization
(which is an fs_initcall) and before device initcalls (including
the pcieport driver initialization) which should avoid the initial
issue.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=100581
Link: http://marc.info/?t=143092384600002&r=1&w=2
Link: https://bugzilla.kernel.org/show_bug.cgi?id=99831
Link: http://marc.info/?t=143389402600001&r=1&w=2
Fixes: b9a5e5e18f "ACPI / init: Fix the ordering of acpi_reserve_resources()"
Reported-by: Roland Dreier <roland@purestorage.com>
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-07-06 23:52:21 +02:00
..
acpi Additional ACPICA material for v4.2-rc1 2015-07-02 17:11:28 -07:00
asm-generic - Support for HS38 cores based on ARCv2 ISA 2015-07-01 09:24:26 -07:00
clocksource ARM: 8366/1: move Dual-Timer SP804 driver to drivers/clocksource 2015-06-02 09:58:18 +01:00
crypto crypto: rng - Do not free default RNG when it becomes unused 2015-06-22 15:49:18 +08:00
drm drm: use kvfree() in drm_free_large() 2015-06-30 19:44:59 -07:00
dt-bindings The changes to the common clock framework for 4.2 are dominated by new 2015-07-01 19:22:00 -07:00
keys
kvm
linux ACPI / PNP: Reserve ACPI resources at the fs_initcall_sync stage 2015-07-06 23:52:21 +02:00
math-emu
media Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds 2015-07-01 19:09:11 -07:00
memory
misc cxl: Add AFU virtual PHB and kernel API 2015-06-03 13:27:20 +10:00
net net: Kill sock->sk_protinfo 2015-06-28 16:55:44 -07:00
pcmcia
ras tracing: add trace event for memory-failure 2015-06-24 17:49:43 -07:00
rdma IB/mad: Add final OPA MAD processing 2015-06-12 14:49:18 -04:00
rxrpc
scsi SCSI misc on 20150622 2015-06-23 15:55:44 -07:00
soc Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm 2015-06-26 12:20:00 -07:00
sound ASoC: Further updates for v4.2 2015-06-22 11:32:41 +02:00
target Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2015-07-04 14:13:43 -07:00
trace Merge branch 'for-linus-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2015-06-30 20:07:45 -07:00
uapi virtio/vhost: cross endian support 2015-07-03 16:02:25 -07:00
video Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2015-06-26 13:18:51 -07:00
xen
Kbuild