Handle alarms with a minute resolution in the core. Until now drivers have
been open coding the seconds part removal and have been doing that wrongly.
Most of them are rounding up which means the allow the system to miss
deadlines. So, round down and let __rtc_set_alarm return immediately if the
time has already passed.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20211107225458.111068-1-alexandre.belloni@bootlin.com
This RTC driver starts counting from 2000 to avoid Y2K problem. Also it
only supports 100 years range for all RTCs. Provide that info to RTC
framework. Also remove check for 100 years range in s3c_rtc_settime(),
as RTC core won't pass any invalid values to the driver, now that
correct range is set.
Here is the rationale on 100 years range limitation. Info on different
Samsung RTCs (credit goes to Krzysztof Kozlowski):
- All S3C chips have only 8-bit wide year register (can store 100
years range in BCD format)
- S5Pv210 and Exynos chips have 12-bit year register (can store 1000
years range in BCD format)
But in reality we usually can't make use of those 12 bits either:
- RTCs might think that both 2000 and 2100 years are leap years. So
when the YEAR register is 0, RTC goes from 28 Feb to 29 Feb, and
when the YEAR register is 100, RTC also goes from 28 Feb to 29 Feb.
This is of course incorrect: RTC breaks leap year criteria, which
breaks the time contiguity, which leads to inability to use the RTC
after year of 2099. It was found for example on Exynos850 SoC.
- Despite having 12 bits for holding the year value, RTC might
overflow the year value internally much earlier. For example, on
Exynos850 the RTC overflows when YEAR=159, making the next YEAR=0.
This way RTC actually has range of 160 years, not 1000 as one may
think.
All that said, there is no sense in trying to increase the time range
for more than 100 years on RTCs that seem capable of that. It also
doesn't have too much practical value -- current hardware will be
probably obsolete by 2100.
Tested manually on Exynos850 RTC:
$ date -s "1999-12-31 23:59:50"
$ hwclock -w -f /dev/rtc0
$ date -s "2100-01-01 00:00:00"
$ hwclock -w -f /dev/rtc0
$ date -s "2000-01-01 00:00:00"
$ hwclock -w -f /dev/rtc0
$ hwclock -r -f /dev/rtc0
$ date -s "2099-12-31 23:59:50"
$ hwclock -w -f /dev/rtc0
$ hwclock -r -f /dev/rtc0
Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20211021202256.28517-4-semen.protsenko@linaro.org
Some SoCs have an RTC supported by this RTC driver, but do not have an
early clock provider declared here. Currently, this prevents the RTC
driver from probing, because it expects a global struct to already be
allocated. Fix probing the driver by copying the missing pieces from the
clock provider setup function, replacing them with the devm variants.
Signed-off-by: Samuel Holland <samuel@sholland.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210928080335.36706-7-samuel@sholland.org
BSM or Backup Switch Mode is a common feature on RTCs, allowing to select
how the RTC will decide when to switch from its primary power supply to the
backup power supply. It is necessary to be able to set it from userspace as
there are uses cases where it has to be done dynamically.
Supported values are:
RTC_BSM_DISABLED: disabled
RTC_BSM_DIRECT: switching will happen as soon as Vbackup > Vdd
RTC_BSM_LEVEL: switching will happen around a threshold, usually with an
hysteresis
RTC_BSM_STANDBY: switching will not happen until Vdd > Vbackup, this is
useful to ensure the RTC doesn't draw any power until the device is first
powered on.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20211018151933.76865-6-alexandre.belloni@bootlin.com
Power-on reset after the insertion of a battery does not always complete
successfully, leading to corrupted register content. The EXT_TEST bit
will stop the clock from running, but currently the driver will never
recover.
Safely handle the erroneous state by clearing EXT_TEST as part of the
usual set_time method.
Signed-off-by: Phil Elwell <phil@raspberrypi.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20211015111208.1757110-1-phil@raspberrypi.com
TQ-Systems' TQMa8Mx module (SoM) uses a pcf85063 as RTC. The default output
is 32768Hz. This is to provide the i.MX8M CKIL clock. Once the RTC driver
is probed, the clock is disabled and all i.MX8M functionality depending on
the 32 KHz clock will halt. In our case the whole system halts and a power
cycle is required.
Referencing the pcf85063 directly results in a deadlock. The kernel
will see, that i.MX8M system clock needs the RTC clock and do probe
deferral. But the i.MX8M I2C module never becomes usable without the
i.MX8M CKIL clock and thus the RTC's clock will not be probed. So
from the kernel's perspective this is a chicken-and-egg problem.
Technically everything is fine by not touching anything, since
the RTC clock correctly enables the clock on reset (i.e. on
battery backup power loss).
A workaround for this issue is describing the square wave pin
as fixed-clock, which is registered early and basically how
this pin is used on the i.MX8M.
This addresses the exact same issue as in commit f765e349c3 ("rtc:
m41t80: add support for fixed clock").
Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
[Fixed return value 0 -> NULL]
Link: https://lore.kernel.org/r/20211013074954.997445-1-alexander.stein@ew.tq-group.com
I got a null-ptr-deref report when doing fault injection test:
BUG: kernel NULL pointer dereference, address: 0000000000000000
RIP: 0010:strcmp+0xc/0x20
Call Trace:
__devm_rtc_register_device.cold.7+0x16a/0x2df
rv3029_probe+0x4b1/0x770 [rtc_rv3029c2]
rv3029_i2c_probe+0x141/0x180 [rtc_rv3029c2]
i2c_device_probe+0xa07/0xbb0
really_probe+0x285/0xc30
If dev_set_name() fails, dev_name() is null, it causes null-ptr-deref,
we need check the return value of dev_set_name().
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20211012041629.2504158-1-yangyingliang@huawei.com
I got a null-ptr-deref report when doing fault injection test:
general protection fault, probably for non-canonical address 0xdffffc0000000022: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000110-0x0000000000000117]
RIP: 0010:device_del+0x132/0xdc0
Call Trace:
cdev_device_del+0x1a/0x80
devm_rtc_unregister_device+0x37/0x80
release_nodes+0xc3/0x3b0
If cdev_device_add() fails, 'dev->p' is not set, it causes
null-ptr-deref when calling cdev_device_del(). Registering
character device is optional, we don't return error code
here, so introduce a new flag 'RTC_NO_CDEV' to indicate
if it has character device, cdev_device_del() is called
when this bit is not set.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20211011132114.3663509-1-yangyingliang@huawei.com
Currently autoloading for SPI devices does not use the DT ID table, it uses
SPI modalises. Supporting OF modalises is going to be difficult if not
impractical, an attempt was made but has been reverted, so ensure that
module autoloading works for this driver by adding an id_table listing the
SPI IDs for everything.
Fixes: 96c8395e21 ("spi: Revert modalias changes")
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210927130240.33693-1-broonie@kernel.org
Currently autoloading for SPI devices does not use the DT ID table, it uses
SPI modalises. Supporting OF modalises is going to be difficult if not
impractical, an attempt was made but has been reverted, so ensure that
module autoloading works for this driver by adding an id_table listing the
SPI IDs for everything.
Fixes: 96c8395e21 ("spi: Revert modalias changes")
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210923194922.53386-4-broonie@kernel.org
Currently autoloading for SPI devices does not use the DT ID table, it uses
SPI modalises. Supporting OF modalises is going to be difficult if not
impractical, an attempt was made but has been reverted, so ensure that
module autoloading works for this driver by adding an id_table listing the
SPI IDs for everything.
Fixes: 96c8395e21 ("spi: Revert modalias changes")
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210923194922.53386-3-broonie@kernel.org
Currently autoloading for SPI devices does not use the DT ID table, it uses
SPI modalises. Supporting OF modalises is going to be difficult if not
impractical, an attempt was made but has been reverted, so ensure that
module autoloading works for this driver by adding an id_table listing the
SPI IDs for everything.
Fixes: 96c8395e21 ("spi: Revert modalias changes")
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210923194922.53386-2-broonie@kernel.org
Pull more perf tools updates from Arnaldo Carvalho de Melo:
- Add missing fields and remove some duplicate fields when printing a
perf_event_attr.
- Fix hybrid config terms list corruption.
- Update kernel header copies, some resulted in new kernel features
being automagically added to 'perf trace' syscall/tracepoint argument
id->string translators.
- Add a file generated during the documentation build to .gitignore.
- Add an option to build without libbfd, as some distros, like Debian
consider its ABI unstable.
- Add support to print a textual representation of IBS raw sample data
in 'perf report'.
- Fix bpf 'perf test' sample mismatch reporting
- Fix passing arguments to stackcollapse report in a 'perf script'
python script.
- Allow build-id with trailing zeros.
- Look for ImageBase in PE file to compute .text offset.
* tag 'perf-tools-for-v5.15-2021-09-11' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (25 commits)
tools headers UAPI: Update tools's copy of drm.h headers
tools headers UAPI: Sync drm/i915_drm.h with the kernel sources
tools headers UAPI: Sync linux/fs.h with the kernel sources
tools headers UAPI: Sync linux/in.h copy with the kernel sources
perf tools: Add an option to build without libbfd
perf tools: Allow build-id with trailing zeros
perf tools: Fix hybrid config terms list corruption
perf tools: Factor out copy_config_terms() and free_config_terms()
perf tools: Fix perf_event_attr__fprintf() missing/dupl. fields
perf tools: Ignore Documentation dependency file
perf bpf: Provide a weak btf__load_from_kernel_by_id() for older libbpf versions
tools include UAPI: Update linux/mount.h copy
perf beauty: Cover more flags in the move_mount syscall argument beautifier
tools headers UAPI: Sync linux/prctl.h with the kernel sources
tools include UAPI: Sync sound/asound.h copy with the kernel sources
tools headers UAPI: Sync linux/kvm.h with the kernel sources
tools headers UAPI: Sync x86's asm/kvm.h with the kernel sources
perf report: Add support to print a textual representation of IBS raw sample data
perf report: Add tools/arch/x86/include/asm/amd-ibs.h
perf env: Add perf_env__cpuid, perf_env__{nr_}pmu_mappings
...
Pull compiler attributes updates from Miguel Ojeda:
- Fix __has_attribute(__no_sanitize_coverage__) for GCC 4 (Marco Elver)
- Add Nick as Reviewer for compiler_attributes.h (Nick Desaulniers)
- Move __compiletime_{error|warning} (Nick Desaulniers)
* tag 'compiler-attributes-for-linus-v5.15-rc1-v2' of git://github.com/ojeda/linux:
compiler_attributes.h: move __compiletime_{error|warning}
MAINTAINERS: add Nick as Reviewer for compiler_attributes.h
Compiler Attributes: fix __has_attribute(__no_sanitize_coverage__) for GCC 4
Pull auxdisplay updates from Miguel Ojeda:
"An assortment of improvements for auxdisplay:
- Replace symbolic permissions with octal permissions (Jinchao Wang)
- ks0108: Switch to use module_parport_driver() (Andy Shevchenko)
- charlcd: Drop unneeded initializers and switch to C99 style (Andy
Shevchenko)
- hd44780: Fix oops on module unloading (Lars Poeschel)
- Add I2C gpio expander example (Ralf Schlatterbeck)"
* tag 'auxdisplay-for-linus-v5.15-rc1' of git://github.com/ojeda/linux:
auxdisplay: Replace symbolic permissions with octal permissions
auxdisplay: ks0108: Switch to use module_parport_driver()
auxdisplay: charlcd: Drop unneeded initializers and switch to C99 style
auxdisplay: hd44780: Fix oops on module unloading
auxdisplay: Add I2C gpio expander example
Pull CPU hotplug updates from Thomas Gleixner:
"Updates for the SMP and CPU hotplug:
- Remove DEFINE_SMP_CALL_CACHE_FUNCTION() which is a left over of the
original hotplug code and now causing trouble with the ARM64 cache
topology setup due to the pointless SMP function call.
It's not longer required as the hotplug callbacks are guaranteed to
be invoked on the upcoming CPU.
- Remove the deprecated and now unused CPU hotplug functions
- Rewrite the CPU hotplug API documentation"
* tag 'smp-urgent-2021-09-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
Documentation: core-api/cpuhotplug: Rewrite the API section
cpu/hotplug: Remove deprecated CPU-hotplug functions.
thermal: Replace deprecated CPU-hotplug functions.
drivers: base: cacheinfo: Get rid of DEFINE_SMP_CALL_CACHE_FUNCTION()
Pull misc driver fix from Greg KH:
"Here is a single patch for 5.15-rc1, for the lkdtm misc driver.
It resolves a build issue that many people were hitting with your
current tree, and Kees and others felt would be good to get merged
before -rc1 comes out, to prevent them from having to constantly hit
it as many development trees restart on -rc1, not older -rc releases.
It has NOT been in linux-next, but has passed 0-day testing and looks
'obviously correct' when reviewing it locally :)"
* tag 'char-misc-5.15-rc1-lkdtm' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
lkdtm: Use init_uts_ns.name instead of macros
Pull IPMI updates from Corey Minyard:
"A couple of very minor fixes for style and rate limiting.
Nothing big, but probably needs to go in"
* tag 'for-linus-5.15-1' of git://github.com/cminyard/linux-ipmi:
char: ipmi: use DEVICE_ATTR helper macro
ipmi: rate limit ipmi smi_event failure message
Pull scheduler fixes from Borislav Petkov:
- Make sure the idle timer expires in hardirq context, on PREEMPT_RT
- Make sure the run-queue balance callback is invoked only on the
outgoing CPU
* tag 'sched_urgent_for_v5.15_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched: Prevent balance_push() on remote runqueues
sched/idle: Make the idle timer expire in hard interrupt context
Pull locking fixes from Borislav Petkov:
- Fix the futex PI requeue machinery to not return to userspace in
inconsistent state
- Avoid a potential null pointer dereference in the ww_mutex deadlock
check
- Other smaller cleanups and optimizations
* tag 'locking_urgent_for_v5.15_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/rtmutex: Fix ww_mutex deadlock check
futex: Remove unused variable 'vpid' in futex_proxy_trylock_atomic()
futex: Avoid redundant task lookup
futex: Clarify comment for requeue_pi_wake_futex()
futex: Prevent inconsistent state and exit race
futex: Return error code instead of assigning it without effect
locking/rwsem: Add missing __init_rwsem() for PREEMPT_RT
Pull timer fix from Borislav Petkov:
- Handle negative second values properly when converting a timespec64
to nanoseconds.
* tag 'timers_urgent_for_v5.15_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
time: Handle negative seconds correctly in timespec64_to_ns()
Pull namei updates from Al Viro:
"Clearing fallout from mkdirat in io_uring series. The fix in the
kern_path_locked() patch plus associated cleanups"
* 'misc.namei' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
putname(): IS_ERR_OR_NULL() is wrong here
namei: Standardize callers of filename_create()
namei: Standardize callers of filename_lookup()
rename __filename_parentat() to filename_parentat()
namei: Fix use after free in kern_path_locked
