rtc: Extend timeout for waiting for UIP to clear to 1s

Specs don't say anything about UIP being cleared within 10ms. They
only say that UIP won't occur for another 244uS. If a long NMI occurs
while

rtc: Extend timeout for waiting for UIP to clear to 1s

Specs don't say anything about UIP being cleared within 10ms. They
only say that UIP won't occur for another 244uS. If a long NMI occurs
while UIP is still updating it might not be possible to get valid
data in 10ms.

This has been observed in the wild that around s2idle some calls can
take up to 480ms before UIP is clear.

Adjust callers from outside an interrupt context to wait for up to a
1s instead of 10ms.

Cc: <[email protected]> # 6.1.y
Fixes: ec5895c0f2d8 ("rtc: mc146818-lib: extract mc146818_avoid_UIP")
Reported-by: Carsten Hatger <[email protected]>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217626
Tested-by: Mateusz Jończyk <[email protected]>
Reviewed-by: Mateusz Jończyk <[email protected]>
Acked-by: Mateusz Jończyk <[email protected]>
Signed-off-by: Mario Limonciello <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Belloni <[email protected]>

show more ...

rtc: Add support for configuring the UIP timeout for RTC reads

The UIP timeout is hardcoded to 10ms for all RTC reads, but in some
contexts this might not be enough time. Add a timeout parameter to

rtc: Add support for configuring the UIP timeout for RTC reads

The UIP timeout is hardcoded to 10ms for all RTC reads, but in some
contexts this might not be enough time. Add a timeout parameter to
mc146818_get_time() and mc146818_get_time_callback().

If UIP timeout is configured by caller to be >=100 ms and a call
takes this long, log a warning.

Make all callers use 10ms to ensure no functional changes.

Cc: <[email protected]> # 6.1.y
Fixes: ec5895c0f2d8 ("rtc: mc146818-lib: extract mc146818_avoid_UIP")
Signed-off-by: Mario Limonciello <[email protected]>
Tested-by: Mateusz Jończyk <[email protected]>
Reviewed-by: Mateusz Jończyk <[email protected]>
Acked-by: Mateusz Jończyk <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Belloni <[email protected]>

show more ...

rtc: Check return value from mc146818_get_time()

There are 4 users of mc146818_get_time() and none of them was checking
the return value from this function. Change this.

Print the appropriate warni

rtc: Check return value from mc146818_get_time()

There are 4 users of mc146818_get_time() and none of them was checking
the return value from this function. Change this.

Print the appropriate warnings in callers of mc146818_get_time() instead
of in the function mc146818_get_time() itself, in order not to add
strings to rtc-mc146818-lib.c, which is kind of a library.

The callers of alpha_rtc_read_time() and cmos_read_time() may use the
contents of (struct rtc_time *) even when the functions return a failure
code. Therefore, set the contents of (struct rtc_time *) to 0x00,
which looks more sensible then 0xff and aligns with the (possibly
stale?) comment in cmos_read_time:

/*
* If pm_trace abused the RTC for storage, set the timespec to 0,
* which tells the caller that this RTC value is unusable.
*/

For consistency, do this in mc146818_get_time().

Note: hpet_rtc_interrupt() may call mc146818_get_time() many times a
second. It is very unlikely, though, that the RTC suddenly stops
working and mc146818_get_time() would consistently fail.

Only compile-tested on alpha.

Signed-off-by: Mateusz Jończyk <[email protected]>
Cc: Richard Henderson <[email protected]>
Cc: Ivan Kokshaysky <[email protected]>
Cc: Matt Turner <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: Alessandro Zummo <[email protected]>
Cc: Alexandre Belloni <[email protected]>
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Alexandre Belloni <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

show more ...

PM: base: power: don't try to use non-existing RTC for storing data

If there is no legacy RTC device, don't try to use it for storing trace
data across suspend/resume.

Cc: <[email protected]>

PM: base: power: don't try to use non-existing RTC for storing data

If there is no legacy RTC device, don't try to use it for storing trace
data across suspend/resume.

Cc: <[email protected]>
Signed-off-by: Juergen Gross <[email protected]>
Reviewed-by: Rafael J. Wysocki <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Juergen Gross <[email protected]>

show more ...

PM: sleep: core: mark 2 functions as __init to save some memory

'early_resume_init()' and 'late_resume_init() 'are only called respectively
via 'early_resume_init' and 'late_resume_init'.

They can

PM: sleep: core: mark 2 functions as __init to save some memory

'early_resume_init()' and 'late_resume_init() 'are only called respectively
via 'early_resume_init' and 'late_resume_init'.

They can be marked as __init to save a few bytes of memory.

Signed-off-by: Christophe JAILLET <[email protected]>
[ rjw: Subject edits ]
Signed-off-by: Rafael J. Wysocki <[email protected]>

show more ...

drivers: base: power: add proper SPDX identifiers on files that did not have them.

There were a few files in the driver core power code that did not have
SPDX identifiers on them, so fix that up. A

drivers: base: power: add proper SPDX identifiers on files that did not have them.

There were a few files in the driver core power code that did not have
SPDX identifiers on them, so fix that up. At the same time, remove the
"free form" text that specified the license of the file, as that is
impossible for any tool to properly parse.

Cc: "Rafael J. Wysocki" <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

PM: Add and use pr_fmt()

Prefix all printk/pr_<level> messages with "PM: " to make the
logging a bit more consistent.

Miscellanea:

o Convert a few printks to pr_<level>
o Whitespace to align to

PM: Add and use pr_fmt()

Prefix all printk/pr_<level> messages with "PM: " to make the
logging a bit more consistent.

Miscellanea:

o Convert a few printks to pr_<level>
o Whitespace to align to open parentheses
o Remove embedded "PM: " from pr_debugs as pr_fmt adds it

Signed-off-by: Joe Perches <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Reviewed-by: Kevin Hilman <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>

show more ...

PM: Switch to use %ptR

Use %ptR instead of open coded variant to print content of
struct rtc_time in human readable format.

Cc: [email protected]
Acked-by: Rafael J. Wysocki <rafael.j.wysock

PM: Switch to use %ptR

Use %ptR instead of open coded variant to print content of
struct rtc_time in human readable format.

Cc: [email protected]
Acked-by: Rafael J. Wysocki <[email protected]>
Signed-off-by: Andy Shevchenko <[email protected]>
Signed-off-by: Alexandre Belloni <[email protected]>

show more ...

timekeeping: Ignore the bogus sleep time if pm_trace is enabled

Power management suspend/resume tracing (ab)uses the RTC to store
suspend/resume information persistently. As a consequence the RTC va

timekeeping: Ignore the bogus sleep time if pm_trace is enabled

Power management suspend/resume tracing (ab)uses the RTC to store
suspend/resume information persistently. As a consequence the RTC value is
clobbered when timekeeping is resumed and tries to inject the sleep time.

Commit a4f8f6667f09 ("timekeeping: Cap array access in timekeeping_debug")
plugged a out of bounds array access in the timekeeping debug code which
was caused by the clobbered RTC value, but we still use the clobbered RTC
value for sleep time injection into kernel timekeeping, which will result
in random adjustments depending on the stored "hash" value.

To prevent this keep track of the RTC clobbering and ignore the invalid RTC
timestamp at resume. If the system resumed successfully clear the flag,
which marks the RTC as unusable, warn the user about the RTC clobber and
recommend to adjust the RTC with 'ntpdate' or 'rdate'.

[jstultz: Fixed up pr_warn formating, and implemented suggestions from Ingo]
[ tglx: Rewrote changelog ]

Originally-from: Thomas Gleixner <[email protected]>
Signed-off-by: Chen Yu <[email protected]>
Signed-off-by: John Stultz <[email protected]>
Acked-by: Pavel Machek <[email protected]>
Acked-by: Thomas Gleixner <[email protected]>
Cc: Prarit Bhargava <[email protected]>
Cc: "Rafael J. Wysocki" <[email protected]>
Cc: Richard Cochran <[email protected]>
Cc: Xunlei Pang <[email protected]>
Cc: Len Brown <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Thomas Gleixner <[email protected]>

show more ...

char/genrtc: x86: remove remnants of asm/rtc.h

Commit 3195ef59cb42 ("x86: Do full rtc synchronization with ntp") had
the side-effect of unconditionally enabling the RTC_LIB symbol on x86,
which in t

char/genrtc: x86: remove remnants of asm/rtc.h

Commit 3195ef59cb42 ("x86: Do full rtc synchronization with ntp") had
the side-effect of unconditionally enabling the RTC_LIB symbol on x86,
which in turn disables the selection of the CONFIG_RTC and
CONFIG_GEN_RTC drivers that contain a two older implementations of
the CONFIG_RTC_DRV_CMOS driver.

This removes x86 from the list for genrtc, and changes all references
to the asm/rtc.h header to instead point to the interfaces
from linux/mc146818rtc.h.

Signed-off-by: Arnd Bergmann <[email protected]>
Acked-by: Geert Uytterhoeven <[email protected]>
Signed-off-by: Alexandre Belloni <[email protected]>

show more ...

PM / sleep: declare __tracedata symbols as char[] rather than char

Accessing more than one byte from a symbol declared simply 'char' is undefined
behavior, as reported by UBSAN:

UBSAN: Undefined b

PM / sleep: declare __tracedata symbols as char[] rather than char

Accessing more than one byte from a symbol declared simply 'char' is undefined
behavior, as reported by UBSAN:

UBSAN: Undefined behaviour in drivers/base/power/trace.c:178:18
load of address ffffffff8203fc78 with insufficient space
for an object of type 'char'

Avoid this by declaring the symbols as arrays.

Signed-off-by: Eric Biggers <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>

show more ...

PM / sleep: add pm-trace support for suspending phase

Occasionally, the system can't come back up after suspend/resume
due to problems of device suspending phase. This patch make
PM_TRACE infrastruc

PM / sleep: add pm-trace support for suspending phase

Occasionally, the system can't come back up after suspend/resume
due to problems of device suspending phase. This patch make
PM_TRACE infrastructure cover device suspending phase of
suspend/resume process, and the information in RTC can tell
developers which device suspending function make system hang.

Signed-off-by: Zhonghui Fu <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>

show more ...

drivers/base: Add export.h for EXPORT_SYMBOL/THIS_MODULE as required.

Most of these files were implicitly getting EXPORT_SYMBOL via
device.h which was including module.h, but that path will be broke

drivers/base: Add export.h for EXPORT_SYMBOL/THIS_MODULE as required.

Most of these files were implicitly getting EXPORT_SYMBOL via
device.h which was including module.h, but that path will be broken
soon.

[ with input from Stephen Rothwell <[email protected]> ]

Signed-off-by: Paul Gortmaker <[email protected]>

show more ...

PM: Add "RTC" to PM trace time stamps to avoid confusion

Some users are apparently confused by dmesg output from
read_magic_time(), which looks like "real" time and date.
Add the "RTC" string to tim

PM: Add "RTC" to PM trace time stamps to avoid confusion

Some users are apparently confused by dmesg output from
read_magic_time(), which looks like "real" time and date.
Add the "RTC" string to time stamps printed by read_magic_time() to
avoid that confusion.

Reported-by: Justin P. Mattock <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>

show more ...

PM: Use appropriate printk() priority level in trace.c

printk()s without a priority level default to KERN_WARNING. To reduce
noise at KERN_WARNING, this patch sets the priority level appriopriately

PM: Use appropriate printk() priority level in trace.c

printk()s without a priority level default to KERN_WARNING. To reduce
noise at KERN_WARNING, this patch sets the priority level appriopriately
for unleveled printks()s. This should be useful to folks that look at
dmesg warnings closely.

Changed these messages to pr_info().

Signed-off-by: Mandeep Singh Baines <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>

show more ...

PM: Add sysfs attr for rechecking dev hash from PM trace

If the device which fails to resume is part of a loadable kernel module
it won't be checked at startup against the magic number stored in the

PM: Add sysfs attr for rechecking dev hash from PM trace

If the device which fails to resume is part of a loadable kernel module
it won't be checked at startup against the magic number stored in the
RTC.

Add a read-only sysfs attribute /sys/power/pm_trace_dev_match which
contains a list of newline separated devices (usually just the one)
which currently match the last magic number. This allows the device
which is failing to resume to be found after the modules are loaded
again.

Signed-off-by: James Hogan <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>

show more ...

PM: Lock PM device list mutex in show_dev_hash()

Lock the PM device list mutex using device_pm_lock() and
device_pm_unlock() around the list iteration in show_dev_hash().

show_dev_hash() was revers

PM: Lock PM device list mutex in show_dev_hash()

Lock the PM device list mutex using device_pm_lock() and
device_pm_unlock() around the list iteration in show_dev_hash().

show_dev_hash() was reverse iterating dpm_list without first locking the
mutex that the functions in drivers/base/power/main.c lock. I assume
this was unintentional since there is no comment suggesting why the lock
might not be necessary.

Signed-off-by: James Hogan <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>

show more ...

driver core: struct device - replace bus_id with dev_name(), dev_set_name()

Signed-off-by: Kay Sievers <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

driver core: fix a lot of printk usages of bus_id

We have the dev_printk() variants for this kind of thing, use them
instead of directly trying to access the bus_id field of struct device.

This is

driver core: fix a lot of printk usages of bus_id

We have the dev_printk() variants for this kind of thing, use them
instead of directly trying to access the bus_id field of struct device.

This is done in order to remove bus_id entirely.

Cc: Kay Sievers <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

Introduce new top level suspend and hibernation callbacks

Introduce 'struct pm_ops' and 'struct pm_ext_ops' ('ext' meaning
'extended') representing suspend and hibernation operations for bus
types,

Introduce new top level suspend and hibernation callbacks

Introduce 'struct pm_ops' and 'struct pm_ext_ops' ('ext' meaning
'extended') representing suspend and hibernation operations for bus
types, device classes, device types and device drivers.

Modify the PM core to use 'struct pm_ops' and 'struct pm_ext_ops'
objects, if defined, instead of the ->suspend(), ->resume(),
->suspend_late(), and ->resume_early() callbacks (the old callbacks
will be considered as legacy and gradually phased out).

The main purpose of doing this is to separate suspend (aka S2RAM and
standby) callbacks from hibernation callbacks in such a way that the
new callbacks won't take arguments and the semantics of each of them
will be clearly specified. This has been requested for multiple
times by many people, including Linus himself, and the reason is that
within the current scheme if ->resume() is called, for example, it's
difficult to say why it's been called (ie. is it a resume from RAM or
from hibernation or a suspend/hibernation failure etc.?).

The second purpose is to make the suspend/hibernation callbacks more
flexible so that device drivers can handle more than they can within
the current scheme. For example, some drivers may need to prevent
new children of the device from being registered before their
->suspend() callbacks are executed or they may want to carry out some
operations requiring the availability of some other devices, not
directly bound via the parent-child relationship, in order to prepare
for the execution of ->suspend(), etc.

Ultimately, we'd like to stop using the freezing of tasks for suspend
and therefore the drivers' suspend/hibernation code will have to take
care of the handling of the user space during suspend/hibernation.
That, in turn, would be difficult within the current scheme, without
the new ->prepare() and ->complete() callbacks.

Signed-off-by: Rafael J. Wysocki <[email protected]>
Acked-by: Pavel Machek <[email protected]>
Signed-off-by: Jesse Barnes <[email protected]>

show more ...

x86: move tracedata to RODATA

.. allowing it to be write-protected just as other read-only data
under CONFIG_DEBUG_RODATA.

Signed-off-by: Jan Beulich <[email protected]>
Signed-off-by: Ingo Molna

x86: move tracedata to RODATA

.. allowing it to be write-protected just as other read-only data
under CONFIG_DEBUG_RODATA.

Signed-off-by: Jan Beulich <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>

show more ...

pm_trace displays the wrong time from the RTC

The way in which read_magic_time() displays the date read from the RTC is
apparently confusing to the users (cf.
https://bugzilla.redhat.com/bugzilla/sh

pm_trace displays the wrong time from the RTC

The way in which read_magic_time() displays the date read from the RTC is
apparently confusing to the users (cf.
https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=250238). Make it
print dates in the standard way.

Signed-off-by: Rafael J. Wysocki <[email protected]>
Acked-by: Dave Jones <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

x86: PM_TRACE support

Signed-off-by: Nigel Cunningham <[email protected]>
Cc: Randy Dunlap <[email protected]>
Cc: "Rafael J. Wysocki" <[email protected]>
Cc: Pavel Machek <[email protected]>
Acked-b

x86: PM_TRACE support

Signed-off-by: Nigel Cunningham <[email protected]>
Cc: Randy Dunlap <[email protected]>
Cc: "Rafael J. Wysocki" <[email protected]>
Cc: Pavel Machek <[email protected]>
Acked-by: Linus Torvalds <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Andi Kleen <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

Add some basic resume trace facilities

Considering that there isn't a lot of hw we can depend on during resume,
this is about as good as it gets.

This is x86-only for now, although the basic concep

Add some basic resume trace facilities

Considering that there isn't a lot of hw we can depend on during resume,
this is about as good as it gets.

This is x86-only for now, although the basic concept (and most of the
code) will certainly work on almost any platform.

Signed-off-by: Linus Torvalds <[email protected]>

show more ...