kernel.git/drivers/acpi/internal.h, branch linux-5.4.y

ACPI: EC: Rework flushing of EC work while suspended to idle

2022-01-27T08:19:32Z

[ Upstream commit 4a9af6cac050dce2e895ec3205c4615383ad9112 ] The flushing of pending work in the EC driver uses drain_workqueue() to flush the event handling work that can requeue itself via advance_transaction(), but this is problematic, because that work may also be requeued from the query workqueue. Namely, if an EC transaction is carried out during the execution of a query handler, it involves calling advance_transaction() which may queue up the event handling work again. This causes the kernel to complain about attempts to add a work item to the EC event workqueue while it is being drained and worst-case it may cause a valid event to be skipped. To avoid this problem, introduce two new counters, events_in_progress and queries_in_progress, incremented when a work item is queued on the event workqueue or the query workqueue, respectively, and decremented at the end of the corresponding work function, and make acpi_ec_dispatch_gpe() the workqueues in a loop until the both of these counters are zero (or system wakeup is pending) instead of calling acpi_ec_flush_work(). At the same time, change __acpi_ec_flush_work() to call flush_workqueue() instead of drain_workqueue() to flush the event workqueue. While at it, use the observation that the work item queued in acpi_ec_query() cannot be pending at that time, because it is used only once, to simplify the code in there. Additionally, clean up a comment in acpi_ec_query() and adjust white space in acpi_ec_event_processor(). Fixes: f0ac20c3f613 ("ACPI: EC: Fix flushing of pending work") Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin

ACPI: scan: Use unique number for instance_no

2021-03-30T12:35:28Z

[ Upstream commit eb50aaf960e3bedfef79063411ffd670da94b84b ] The decrementation of acpi_device_bus_id->instance_no in acpi_device_del() is incorrect, because it may cause a duplicate instance number to be allocated next time a device with the same acpi_device_bus_id is added. Replace above mentioned approach by using IDA framework. While at it, define the instance range to be [0, 4096). Fixes: e49bd2dd5a50 ("ACPI: use PNPID:instance_no as bus_id of ACPI device") Fixes: ca9dc8d42b30 ("ACPI / scan: Fix acpi_bus_id_list bookkeeping") Signed-off-by: Andy Shevchenko Cc: 4.10+ # 4.10+ Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin

ACPI: scan: Harden acpi_device_add() against device ID overflows

2021-01-19T17:26:12Z

commit a58015d638cd4e4555297b04bec9b49028369075 upstream. Linux VM on Hyper-V crashes with the latest mainline: [ 4.069624] detected buffer overflow in strcpy [ 4.077733] kernel BUG at lib/string.c:1149! .. [ 4.085819] RIP: 0010:fortify_panic+0xf/0x11 ... [ 4.085819] Call Trace: [ 4.085819] acpi_device_add.cold.15+0xf2/0xfb [ 4.085819] acpi_add_single_object+0x2a6/0x690 [ 4.085819] acpi_bus_check_add+0xc6/0x280 [ 4.085819] acpi_ns_walk_namespace+0xda/0x1aa [ 4.085819] acpi_walk_namespace+0x9a/0xc2 [ 4.085819] acpi_bus_scan+0x78/0x90 [ 4.085819] acpi_scan_init+0xfa/0x248 [ 4.085819] acpi_init+0x2c1/0x321 [ 4.085819] do_one_initcall+0x44/0x1d0 [ 4.085819] kernel_init_freeable+0x1ab/0x1f4 This is because of the recent buffer overflow detection in the commit 6a39e62abbaf ("lib: string.h: detect intra-object overflow in fortified string functions") Here acpi_device_bus_id->bus_id can only hold 14 characters, while the the acpi_device_hid(device) returns a 22-char string "HYPER_V_GEN_COUNTER_V1". Per ACPI Spec v6.2, Section 6.1.5 _HID (Hardware ID), if the ID is a string, it must be of the form AAA#### or NNNN####, i.e. 7 chars or 8 chars. The field bus_id in struct acpi_device_bus_id was originally defined as char bus_id[9], and later was enlarged to char bus_id[15] in 2007 in the commit bb0958544f3c ("ACPI: use more understandable bus_id for ACPI devices") Fix the issue by changing the field bus_id to const char *, and use kstrdup_const() to initialize it. Signed-off-by: Dexuan Cui Tested-By: Jethro Beekman [ rjw: Subject change, whitespace adjustment ] Cc: All applicable Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

ACPI: EC: PM: Avoid premature returns from acpi_s2idle_wake()

2020-05-20T06:20:18Z

[ Upstream commit 7b301750f7f8f6503e11f1af4a03832525f58c66 ] If the EC GPE status is not set after checking all of the other GPEs, acpi_s2idle_wake() returns 'false', to indicate that the SCI event that has just triggered is not a system wakeup one, but it does that without canceling the pending wakeup and re-arming the SCI for system wakeup which is a mistake, because it may cause s2idle_loop() to busy spin until the next valid wakeup event. [If that happens, the first spurious wakeup is still pending after acpi_s2idle_wake() has returned, so s2idle_enter() does nothing, acpi_s2idle_wake() is called again and it sees that the SCI has triggered, but no GPEs are active, so 'false' is returned again, and so on.] Fix that by moving all of the GPE checking logic from acpi_s2idle_wake() to acpi_ec_dispatch_gpe() and making the latter return 'true' only if a non-EC GPE has triggered and 'false' otherwise, which will cause acpi_s2idle_wake() to cancel the pending SCI wakeup and re-arm the SCI for system wakeup regardless of the EC GPE status. This also addresses a lockup observed on an Elitegroup EF20EA laptop after attempting to wake it up from suspend-to-idle by a key press. Fixes: d5406284ff80 ("ACPI: PM: s2idle: Refine active GPEs check") Link: https://bugzilla.kernel.org/show_bug.cgi?id=207603 Reported-by: Todd Brandt Fixes: fdde0ff8590b ("ACPI: PM: s2idle: Prevent spurious SCIs from waking up the system") Link: https://lore.kernel.org/linux-acpi/CAB4CAwdqo7=MvyG_PE+PGVfeA17AHF5i5JucgaKqqMX6mjArbQ@mail.gmail.com/ Reported-by: Chris Chiu Tested-by: Chris Chiu Cc: 5.4+ # 5.4+ Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin

ACPI: PM: s2idle: Refine active GPEs check

2020-04-17T08:50:09Z

commit d5406284ff803a578ca503373624312770319054 upstream. The check for any active GPEs added by commit fdde0ff8590b ("ACPI: PM: s2idle: Prevent spurious SCIs from waking up the system") turns out to be insufficiently precise to prevent some systems from resuming prematurely due to a spurious EC wakeup, so refine it by first checking if any GPEs other than the EC GPE are active and skipping all of the SCIs coming from the EC that do not produce any genuine wakeup events after processing. Link: https://bugzilla.kernel.org/show_bug.cgi?id=206629 Fixes: fdde0ff8590b ("ACPI: PM: s2idle: Prevent spurious SCIs from waking up the system") Reported-by: Ondřej Caletka Tested-by: Ondřej Caletka Cc: 5.4+ # 5.4+ Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

ACPI: EC: PM: Consolidate some code depending on PM_SLEEP

2019-08-08T09:25:43Z

Move some routines, including acpi_ec_dispatch_gpe(), that are only used if CONFIG_PM_SLEEP is set to the #ifdef block containing the EC suspend and resume callbacks, to make the "full EC PM picture" easier to follow. While at it, move the header of acpi_ec_dispatch_gpe() in the header file to a CONFIG_PM_SLEEP #ifdef block. Signed-off-by: Rafael J. Wysocki Tested-by: Kai-Heng Feng

ACPI: PM: s2idle: Eliminate acpi_sleep_no_ec_events()

2019-08-08T09:25:37Z

Change acpi_ec_suspend() to use pm_suspend_no_platform() instead of acpi_sleep_no_ec_events(), which allows the latter to be eliminated along with the s2idle_in_progress variable which is only used by it. Signed-off-by: Rafael J. Wysocki Tested-by: Kai-Heng Feng

ACPI: PM: Set up EC GPE for system wakeup from drivers that need it

2019-07-30T10:26:21Z

The EC GPE needs to be set up for system wakeup only if there is a driver depending on it, either intel-hid or intel-vbtn, bound to a button device that is expected to wake up the system from sleep (such as the power button on some Dell systems, like the XPS13 9360). It doesn't need to be set up for waking up the system from sleep in any other cases and whether or not it is expected to wake up the system from sleep doesn't depend on whether or not the LPS0 device is present in the ACPI namespace. For this reason, rearrange the ACPI suspend-to-idle code to make the drivers depending on the EC GPE wakeup take care of setting it up and decouple that from the LPS0 device handling. While at it, make intel-hid and intel-vbtn prepare for system wakeup only if they are allowed to wake up the system from sleep by user space (via sysfs). [Note that acpi_ec_mark_gpe_for_wake() and acpi_ec_set_gpe_wake_mask() are there to prevent the EC GPE from being disabled by the acpi_enable_all_wakeup_gpes() call in acpi_s2idle_prepare(), so on systems with either intel-hid or intel-vbtn this change doesn't affect any interactions with the hardware or platform firmware.] Signed-off-by: Rafael J. Wysocki Reviewed-by: Andy Shevchenko

ACPI: EC: Return bool from acpi_ec_dispatch_gpe()

2019-07-23T07:46:20Z

On some systems, if suspend-to-idle is used, the EC may signal system wakeup events (power button events, for example) as well as events that should not cause the system to resume and acpi_ec_dispatch_gpe() needs to be called to determine whether or not the system should resume then. In particular, if acpi_ec_dispatch_gpe() doesn't detect any EC events at all, the system should remain suspended, so it is useful to know when that is the case. For this reason, make acpi_ec_dispatch_gpe() return a bool value indicating whether or not any EC events have been detected by it. Signed-off-by: Rafael J. Wysocki Acked-by: Thomas Gleixner

ACPI: PM: Unexport acpi_device_get_power()

2019-07-04T08:49:57Z

Using acpi_device_get_power() outside of ACPI device initialization and ACPI sysfs is problematic due to the way in which power resources are handled by it, so unexport it and add a paragraph explaining the pitfalls to its kerneldoc comment. Signed-off-by: Rafael J. Wysocki Reviewed-by: Mika Westerberg