On HP 250 G1 laptops, BIOS reports minimum backlight on boot and
causes backlight to dim completely. This ignores the initial backlight
values and set to max brightness.
References: https://bugzilla.kernel.org/show_bug.cgi?id=63111
Signed-off-by: Kirill Tkhai <tkhai@yandex.ru>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Memory error reporting is much too verbose. Most users do not care about
the DIMM internal bank/row/column information. Downgrade the fine details
to "pr_debug" status so that those few who do care can get them if they
really want to. The detail information will be later be provided by
perf/trace interface.
Since things are still a bit scary, and users are sometimes overly
nervous, provide a reassuring message that corrected errors do not
generally require any further action.
Suggested-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Chen, Gong <gong.chen@linux.intel.com>
Reviewed-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
After H/W error happens under FFM enabled mode, lots of information
are shown but new fields added by UEFI 2.4 (e.g. DIMM location) need to
be added.
Original-author: Tony Luck <tony.luck@intel.com>
Signed-off-by: Chen, Gong <gong.chen@linux.intel.com>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
In latest UEFI spec(by now it is 2.4) memory error definition
for CPER (UEFI 2.4 Appendix N Common Platform Error Record)
adds some new fields. These fields help people to locate
memory error to an actual DIMM location.
Original-author: Tony Luck <tony.luck@intel.com>
Signed-off-by: Chen, Gong <gong.chen@linux.intel.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
This H/W error log driver (a.k.a eMCA driver) is implemented based on
http://www.intel.com/content/www/us/en/architecture-and-technology/enhanced-mca-logging-xeon-paper.html
After errors are captured, more detailed platform specific information
can be got via this new enhanced H/W error log driver. Most notably we
can track memory errors back to the DIMM slot silk screen label.
Signed-off-by: Chen, Gong <gong.chen@linux.intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
We have a lot of confusing names of functions and data structures in
amongs the the error reporting code. In particular the "apei" prefix
has been applied to many objects that are not part of APEI. Since we
will be using these routines for extended error log reporting it will
be clearer if we fix up the names first.
Signed-off-by: Chen, Gong <gong.chen@linux.intel.com>
Acked-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Commit aaf9d93be71c:
ACPI / APEI: fix error status check condition for CPER
only catches condition check before print, but a similar check is
needed during printing CPER error sections.
Signed-off-by: Chen, Gong <gong.chen@linux.intel.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
"str" is never NULL here so I have removed the check. There are static
checkers which complain about superfluous NULL checks because it may
indicate confusion or a bug.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Two functions defined in device_pm.c, acpi_dev_pm_add_dependent()
and acpi_dev_pm_remove_dependent(), have no callers and may be
dropped, so drop them.
Moreover, they are the only functions adding entries to and removing
entries from the power_dependent list in struct acpi_device, so drop
that list too.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The mechanism causing devices depending on a given power resource
(that is, devices that can be in D0 only if that power resource is
on) to be resumed automatically when the power resource is turned
on (and their "inferred" power state becomes D0 as a result) is
inherently racy and in fact unnecessary.
It is racy, because if the power resource is turned on and then
immediately off, the device resume triggered by the first transition
to "on" may still happen, causing the power resource to be turned
on again. That again will trigger the "resume of dependent devices"
mechanism, but if the devices in question are not in use, they will
be suspended in the meantime causing the power resource to be turned
off. However, the "resume of dependent devices" will next resume
them again and so on. In some cases (USB port PM in particular) that
leads to an endless busy loop of flipping the resource on and off
continuously.
It is needless, because whoever turns a power resource on will most
likely turn it off at some point and the devices that go into "D0"
as a result of turning it on will then go back into D3cold
(generally, the state they were in before).
Moreover, turning on all power resources a device needs to go into
D0 is not sufficient for a full transition into D0 in general.
Namely, _PS0 may need to be executed in addition to that in some
cases. This means that the whole rationale of the "resume of
dependent devices" mechanism was incorrect to begin with and it's
best to remove it entirely.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This adds ACPI ID for Broadcom GPS receiver BCM4752.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
On the Yoga 13 the backlight control doesn't work via ACPI. (And doesn't
work either with the low-level platform driver ideapad_laptop; but
works correctly via the intel video driver). This patch hence adds the
Yoga 13 to the ACPI video detect blacklist, to make sure the broken ACPI
backlight device is never exposed to userspace.
Note that this appears unrelated to the Windows 8 backlight issues tracked
here:
https://bugzilla.kernel.org/show_bug.cgi?id=51231https://bugzilla.kernel.org/show_bug.cgi?id=60682
The Yoga's ACPI backlight controls work neither with nor without
acpi_osi="!Windows 2012" on the kernel command line. It appears that
backlight control via the EC simply is not available at all, regardless
whether done via ACPI or via the vendor driver.
Signed-off-by: Lennart Poettering <lennart@poettering.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
AC's proc directory is not used and so remove it. Prepare for removing
/proc/acpi directory.
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
According to Matthew Garrett, "Windows 8 leaves backlight control up
to individual graphics drivers rather than making ACPI calls itself.
There's plenty of evidence to suggest that the Intel driver for
Windows [8] doesn't use the ACPI interface, including the fact that
it's broken on a bunch of machines when the OS claims to support
Windows 8. The simplest thing to do appears to be to disable the
ACPI backlight interface on these systems".
So for Win8 systems, if there is native backlight control interface
registered by GPU driver, ACPI video does not need to register its own.
Since there are systems that don't work well with this approach, a
parameter for video module named use_native_backlight is introduced and
has the value of false by default. For users who have a broken ACPI
video backlight interface, video.use_native_backlight=1 is needed in
kernel cmdline.
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The backlight control and event delivery functionality provided by ACPI
video module is mixed together and registered all during video device
enumeration time. As a result, the two functionality are also removed
together on module unload time or by the acpi_video_unregister function.
The two functionalities are actually independent and one may be useful
while the other one may be broken, so it is desirable to seperate the
two functionalities such that it is clear and easy to disable one
functionality without affecting the other one.
APIs to selectively remove backlight control interface and/or event
delivery functionality can be easily added once needed.
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit 1696d9d (ACPI: Remove the old /proc/acpi/event interface)
left /proc/acpi/event in the ACPI_BUTTON help in Kconfig, so
remove it from there.
[rjw: Changelog]
Signed-off-by: Krzysztof Mazur <krzysiek@podlesie.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In acpi_resume_power_resources() resource_lock should be released
when acpi_power_get_state() fails and before passing to next power
resource on the list.
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Correct spelling typo within various part of the kernel
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Alarm proc file provides the info and control of RTC-CMOS alarm and
RTC CMOS driver provides wakealarm sysfs attribute for the same
purpose. The alarm file isn't compiled into kernel when RTC CMOS
driver is selected. The driver is default to be selected for x86
platform. So alarm file is default not to include. This patch is
to remove it to prepare remove /proc/acpi directory.
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
There is no user of cm_sbs.c and CONFIG_ACPI_PROCFS_POWER. So remove
them. Prepare for removing /proc/acpi
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
SBS's proc directory isn't useded and so remove it. Prepare for removing
/proc/acpi directory.
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The battery's proc directory isn't useded and remove it.
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Some links to projects web pages and e-mail addresses in ACPI/PM
documentation and Kconfig are outdated, so update them.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Some serial buses like I2C and SPI don't require that the parent device is
in D0 before any of its children transitions to D0, but instead the parent
device can control its own power independently from the children.
This does not follow the ACPI specification as it requires the parent to be
powered on before its children. However, Windows seems to ignore this
requirement so I think we can do the same in Linux.
Implement this by adding a new power flag 'ignore_parent' to struct
acpi_device. If this flag is set the ACPI core ignores checking of the
parent device power state when the device is powered on/off.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The current version requires one to know the size of the package
a priori; this is almost impossible if the package is composed of
strings of variable length. This change allows the utility to
allocate a buffer of the proper size if asked.
Signed-off-by: Al Stone <al.stone@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
There is an additional bit in the GENERAL register on newer
silicon that needs to be set or UART's RTS pin fails to
reflect the flow control settings in the Modem Control
Register.
This will fix an issue where the RTS pin of the UART stays
always at 1.8V, regardless of the register settings.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This adds ACPI IDs for Intel Smart Sound Technology (SST) device found in
Intel Haswell and BayTrail platforms.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
We already have predefined marco for method name "_STA', so
using the marco instead of directly using the string.
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In my original patch[1] I wrote a comment describing the reason for
disabling Windows 2012 OSI mode for a group of machines, however, due to
unknown reasons (probably a conflict resolution mismatch), the comment
was dropped in 94fb982 (ACPI: blacklist win8 OSI for buggy laptops).
Since Matthew Garrett is making a big deal out of the lack of comments
in a separate patch[2], it might make sense to re-introduce the missing
comment so that other patch is not blocked and users don't suffer.
[1] http://article.gmane.org/gmane.linux.acpi.devel/63427
[2] http://thread.gmane.org/gmane.linux.kernel/1572459
Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
More people have reported they need this for their machines to work
correctly.
References: https://bugzilla.kernel.org/show_bug.cgi?id=60682
Reported-by: Stefan Hellermann <bugzilla.kernel.org@the2masters.de>
Reported-by: Benedikt Sauer <filmor@gmail.com>
Reported-by: Erno Kuusela <erno@iki.fi>
Reported-by: Jonathan Doman <jonathan.doman@gmail.com>
Reported-by: Christoph Klaffl <christophklaffl@gmail.com>
Reported-by: Jan Hendrik Nielsen <jan.hendrik.nielsen@informatik.hu-berlin.de>
Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.14 (GNU/Linux)
iQEcBAABAgAGBQJSUc9zAAoJEHm+PkMAQRiG9DMH/AtpuAF6LlMRPjrCeuJQ1pyh
T0IUO+CsLKO6qtM5IyweP8V6zaasNjIuW1+B6IwVIl8aOrM+M7CwRiKvpey26ldM
I8G2ron7hqSOSQqSQs20jN2yGAqQGpYIbTmpdGLAjQ350NNNvEKthbP5SZR5PAmE
UuIx5OGEkaOyZXvCZJXU9AZkCxbihlMSt2zFVxybq2pwnGezRUYgCigE81aeyE0I
QLwzzMVdkCxtZEpkdJMpLILAz22jN4RoVDbXRa2XC7dA9I2PEEXI9CcLzqCsx2Ii
8eYS+no2K5N2rrpER7JFUB2B/2X8FaVDE+aJBCkfbtwaYTV9UYLq3a/sKVpo1Cs=
=xSFJ
-----END PGP SIGNATURE-----
Merge tag 'v3.12-rc4' into sched/core
Merge Linux v3.12-rc4 to fix a conflict and also to refresh the tree
before applying more scheduler patches.
Conflicts:
arch/avr32/include/asm/Kbuild
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fixed a brace coding style issue. (Brace not on the good line)
Signed-off-by: Mathieu Rhéaume <mathieu@codingrhemes.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit caf5c03f (ACPI: Move acpi_bus_get_device() from bus.c to
scan.c) caused acpi_bus_get_device() to be exported using
EXPORT_SYMBOL_GPL(), but that broke some binary drivers in
existence, so revert that change.
Reported-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Convert printks to pr_* format. Additionally re-use PREFIX constant instead of
hardcoded strings.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Use kobject_init_and_add() since we have nothing special to do between
kobject_init() and kobject_add().
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
kobject_add() sets the parent pointer, so we don't need to do it
explicitly.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Set the kobject name via kobject_add() instead of using kobject_set_name(),
which is deprecated per Documentation/kobject.txt.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This patch only introduces indentation cleanups. No functional changes.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This (trivial) patch:
1. Deletes duplicate Kconfig dependency as there is "if IPMI_HANDLER"
around "IPMI_SI".
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Reviewed-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This (trivial) patch:
1. Deletes several useless header inclusions.
2. Kernel codes should always include <linux/acpi.h> instead of
<acpi/acpi_bus.h> or <acpi/acpi_drivers.h> where many conditional
declarations are handled.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Reviewed-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This (trivial) patch.
1. Changes dynamic mutex initialization to static initialization.
2. Removes one acpi_ipmi_init() variable initialization as it is not
needed.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Reviewed-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This (trivial) patch:
1. Deletes a member of the acpi_ipmi_device, smi_data, which is not
actually used.
2. Updates a member of the acpi_ipmi_device, pnp_dev, which is only used
by dev_warn() invocations, so changes it to a struct device.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Reviewed-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This patch adds reference counting for ACPI IPMI transfers to tune the
locking granularity of tx_msg_lock.
This patch also makes the whole acpi_ipmi module's coding style consistent
by using reference counting for all its objects (i.e., acpi_ipmi_device and
acpi_ipmi_msg).
The acpi_ipmi_msg handling is re-designed using referece counting.
1. tx_msg is always unlinked before complete(), so that it is safe to put
complete() out side of tx_msg_lock.
2. tx_msg reference counters are incremented before calling
ipmi_request_settime() and tx_msg_lock protection is added to
ipmi_cancel_tx_msg() so that a complete() can be safely called in
parellel with tx_msg unlinking in failure cases.
3. tx_msg holds a reference to acpi_ipmi_device so that it can be flushed
and freed in the contexts other than acpi_ipmi_space_handler().
The lockdep_chains shows all acpi_ipmi locks are leaf locks after the
tuning:
1. ipmi_lock is always leaf:
irq_context: 0
[ffffffff81a943f8] smi_watchers_mutex
[ffffffffa06eca60] driver_data.ipmi_lock
irq_context: 0
[ffffffff82767b40] &buffer->mutex
[ffffffffa00a6678] s_active#103
[ffffffffa06eca60] driver_data.ipmi_lock
2. without this patch applied, lock used by complete() is held after
holding tx_msg_lock:
irq_context: 0
[ffffffff82767b40] &buffer->mutex
[ffffffffa00a6678] s_active#103
[ffffffffa06ecce8] &(&ipmi_device->tx_msg_lock)->rlock
irq_context: 1
[ffffffffa06ecce8] &(&ipmi_device->tx_msg_lock)->rlock
irq_context: 1
[ffffffffa06ecce8] &(&ipmi_device->tx_msg_lock)->rlock
[ffffffffa06eccf0] &x->wait#25
irq_context: 1
[ffffffffa06ecce8] &(&ipmi_device->tx_msg_lock)->rlock
[ffffffffa06eccf0] &x->wait#25
[ffffffff81e36620] &p->pi_lock
irq_context: 1
[ffffffffa06ecce8] &(&ipmi_device->tx_msg_lock)->rlock
[ffffffffa06eccf0] &x->wait#25
[ffffffff81e36620] &p->pi_lock
[ffffffff81e5d0a8] &rq->lock
3. with this patch applied, tx_msg_lock is always leaf:
irq_context: 0
[ffffffff82767b40] &buffer->mutex
[ffffffffa00a66d8] s_active#107
[ffffffffa07ecdc8] &(&ipmi_device->tx_msg_lock)->rlock
irq_context: 1
[ffffffffa07ecdc8] &(&ipmi_device->tx_msg_lock)->rlock
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Reviewed-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
It is found on a real machine, in its ACPI namespace, the IPMI
OperationRegions (in the ACPI000D - ACPI power meter) are not defined under
the IPMI system interface device (the IPI0001 with KCS type returned from
_IFT control method):
Device (PMI0)
{
Name (_HID, "ACPI000D") // _HID: Hardware ID
OperationRegion (SYSI, IPMI, 0x0600, 0x0100)
Field (SYSI, BufferAcc, Lock, Preserve)
{
AccessAs (BufferAcc, 0x01),
Offset (0x58),
SCMD, 8,
GCMD, 8
}
OperationRegion (POWR, IPMI, 0x3000, 0x0100)
Field (POWR, BufferAcc, Lock, Preserve)
{
AccessAs (BufferAcc, 0x01),
Offset (0xB3),
GPMM, 8
}
}
Device (PCI0)
{
Device (ISA)
{
Device (NIPM)
{
Name (_HID, EisaId ("IPI0001")) // _HID: Hardware ID
Method (_IFT, 0, NotSerialized) // _IFT: IPMI Interface Type
{
Return (0x01)
}
}
}
}
Current ACPI_IPMI code registers IPMI operation region handler on a
per-device basis, so for the above namespace the IPMI operation region
handler is registered only under the scope of \_SB.PCI0.ISA.NIPM. Thus
when an IPMI operation region field of \PMI0 is accessed, there are errors
reported on such platform:
ACPI Error: No handlers for Region [IPMI]
ACPI Error: Region IPMI(7) has no handler
The solution is to install an IPMI operation region handler from root node
so that every object that defines IPMI OperationRegion can get an address
space handler registered.
When an IPMI operation region field is accessed, the Network Function
(0x06 for SYSI and 0x30 for POWR) and the Command (SCMD, GCMD, GPMM) are
passed to the operation region handler, there is no system interface
specified by the BIOS. The patch tries to select one system interface by
monitoring the system interface notification. IPMI messages passed from
the ACPI codes are sent to this selected global IPMI system interface.
The ACPI_IPMI will always select the first registered IPMI interface
with an ACPI handle (i.e., defined in the ACPI namespace). It's hard to
determine the selection when there are multiple IPMI system interfaces
defined in the ACPI namespace. According to the IPMI specification:
A BMC device may make available multiple system interfaces, but only one
management controller is allowed to be 'active' BMC that provides BMC
functionality for the system (in case of a 'partitioned' system, there
can be only one active BMC per partition). Only the system interface(s)
for the active BMC allowed to respond to the 'Get Device Id' command.
According to the ipmi_si desigin:
The ipmi_si registeration notifications can only happen after a
successful "Get Device ID" command.
Thus it should be OK for non-partitioned systems to do such selection.
However, we do not have much knowledge on 'partitioned' systems.
References: https://bugzilla.kernel.org/show_bug.cgi?id=46741
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Reviewed-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This patch uses reference counting to fix the race caused by the
unprotected ACPI IPMI user.
There are two rules for using the ipmi_si APIs:
1. In ipmi_si, ipmi_destroy_user() can ensure that no ipmi_recv_msg will
be passed to ipmi_msg_handler(), but ipmi_request_settime() can not
use an invalid ipmi_user_t. This means the ipmi_si users must ensure
that there won't be any local references on ipmi_user_t before invoking
ipmi_destroy_user().
2. In ipmi_si, the smi_gone()/new_smi() callbacks are protected by
smi_watchers_mutex, so their execution is serialized. But as a
new smi can re-use a freed intf_num, it requires that the callback
implementation must not use intf_num as an identification mean or it
must ensure all references to the previous smi are all dropped before
exiting smi_gone() callback.
As the acpi_ipmi_device->user_interface check in acpi_ipmi_space_handler()
can happen before setting user_interface to NULL and codes after the check
in acpi_ipmi_space_handler() can happen after user_interface becomes NULL,
the on-going acpi_ipmi_space_handler() still can pass an invalid
acpi_ipmi_device->user_interface to ipmi_request_settime(). Such race
conditions are not allowed by the IPMI layer's API design as a crash will
happen in ipmi_request_settime() if something like that happens.
This patch follows the ipmi_devintf.c design:
1. Invoke ipmi_destroy_user() after the reference count of
acpi_ipmi_device drops to 0. References of acpi_ipmi_device dropping
to 0 also means tx_msg related to this acpi_ipmi_device are all freed.
This matches the IPMI layer's API calling rule on ipmi_destroy_user()
and ipmi_request_settime().
2. ipmi_flush_tx_msg() is performed so that no on-going tx_msg can still be
running in acpi_ipmi_space_handler(). And it is invoked after invoking
__ipmi_dev_kill() where acpi_ipmi_device is deleted from the list with a
"dead" flag set, and the "dead" flag check is also introduced to the
point where a tx_msg is going to be added to the tx_msg_list so that no
new tx_msg can be created after returning from the __ipmi_dev_kill().
3. The waiting codes in ipmi_flush_tx_msg() is deleted because it is not
required since this patch ensures no acpi_ipmi reference is still held
for ipmi_user_t before calling ipmi_destroy_user() and
ipmi_destroy_user() can ensure no more ipmi_msg_handler() can happen
after returning from ipmi_destroy_user().
4. The flushing of tx_msg is also moved out of ipmi_lock in this patch.
The forthcoming IPMI operation region handler installation changes also
requires acpi_ipmi_device be handled in this style.
The header comment of the file is also updated due to this design change.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Reviewed-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This patch fixes races caused by timed out ACPI IPMI transfers.
This patch uses timeout mechanism provided by ipmi_si to avoid the race
that the msg_done flag is set but without any protection, its content can
be invalid. Thanks for the suggestion of Corey Minyard.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Reviewed-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This patch fixes races caused by unprotected ACPI IPMI transfers.
We can see that the following crashes may occur:
1. There is no tx_msg_lock held for iterating tx_msg_list in
ipmi_flush_tx_msg() while it may be unlinked on failure in
parallel in acpi_ipmi_space_handler() under tx_msg_lock.
2. There is no lock held for freeing tx_msg in acpi_ipmi_space_handler()
while it may be accessed in parallel in ipmi_flush_tx_msg() and
ipmi_msg_handler().
This patch enhances tx_msg_lock to protect all tx_msg accesses to solve
this issue. Then tx_msg_lock is always held around complete() and tx_msg
accesses.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Reviewed-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This patch enhances sanity checks on message size to avoid potential buffer
overflow.
The kernel IPMI message size is IPMI_MAX_MSG_LENGTH(272 bytes) while the
ACPI specification defined IPMI message size is 64 bytes. The difference
is not handled by the original codes. This may cause crash in the response
handling codes.
This patch closes this gap and also combines rx_data/tx_data to use single
data/len pair since they need not be seperate.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Reviewed-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Once thermal zone is disabled to move thermal control to user space,
too many warnings printed in logs. Remove pr_warn from this path,
instead warn when user mode issues request to disable thermal zone.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Acked-by: Eduardo Valentin <eduardo.valentin@ti.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
