linux-yocto/drivers/rtc
Mateusz Jończyk 39617dc3fa rtc: cmos: use spin_lock_irqsave in cmos_interrupt
commit 00a39d8652 upstream.

cmos_interrupt() can be called in a non-interrupt context, such as in
an ACPI event handler (which runs in an interrupt thread). Therefore,
usage of spin_lock(&rtc_lock) is insecure. Use spin_lock_irqsave() /
spin_unlock_irqrestore() instead.

Before a misguided
commit 6950d046eb ("rtc: cmos: Replace spin_lock_irqsave with spin_lock in hard IRQ")
the cmos_interrupt() function used spin_lock_irqsave(). That commit
changed it to spin_lock() and broke locking, which was partially fixed in
commit 13be2efc39 ("rtc: cmos: Disable irq around direct invocation of cmos_interrupt()")

That second commit did not take account of the ACPI fixed event handler
pathway, however. It introduced local_irq_disable() workarounds in
cmos_check_wkalrm(), which can cause problems on PREEMPT_RT kernels
and are now unnecessary.

Add an explicit comment so that this change will not be reverted by
mistake.

Cc: stable@vger.kernel.org
Fixes: 6950d046eb ("rtc: cmos: Replace spin_lock_irqsave with spin_lock in hard IRQ")
Signed-off-by: Mateusz Jończyk <mat.jonczyk@o2.pl>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: Chris Bainbridge <chris.bainbridge@gmail.com>
Reported-by: Chris Bainbridge <chris.bainbridge@gmail.com>
Closes: https://lore.kernel.org/all/aDtJ92foPUYmGheF@debian.local/
Link: https://lore.kernel.org/r/20250607210608.14835-1-mat.jonczyk@o2.pl
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-07-10 16:03:03 +02:00
..
class.c rtc: Fix offset calculation for .start_secs < 0 2025-06-19 15:27:59 +02:00
dev.c
interface.c rtc: check if __rtc_read_time was successful in rtc_timer_do_work() 2024-12-09 10:32:55 +01:00
Kconfig rtc: mt6397: select IRQ_DOMAIN instead of depending on it 2024-03-26 18:20:06 -04:00
lib_test.c rtc: test: Fix invalid format specifier. 2024-03-26 18:19:18 -04:00
lib.c rtc: Make rtc_time64_to_tm() support dates before 1970 2025-06-19 15:27:59 +02:00
Makefile rtc: Add rtc driver for the Loongson family chips 2023-06-26 01:19:11 +02:00
nvmem.c nvmem: add explicit config option to read old syntax fixed OF cells 2024-05-17 12:01:55 +02:00
proc.c
rtc-88pm80x.c rtc: 88pm80x: Convert to platform remove callback returning void 2023-03-17 23:03:16 +01:00
rtc-88pm860x.c rtc: 88pm860x: Convert to platform remove callback returning void 2023-03-17 23:03:16 +01:00
rtc-ab-b5ze-s3.c rtc: Switch i2c drivers back to use .probe() 2023-06-06 23:29:37 +02:00
rtc-ab-eoz9.c rtc: ab-eoz9: don't fail temperature reads on undervoltage notification 2024-12-09 10:32:57 +01:00
rtc-ab8500.c rtc: ab8500: Convert to platform remove callback returning void 2023-03-17 23:03:16 +01:00
rtc-abx80x.c rtc: abx80x: Fix WDT bit position of the status register 2024-12-09 10:32:55 +01:00
rtc-ac100.c rtc: ac100: Convert to platform remove callback returning void 2023-03-17 23:03:17 +01:00
rtc-armada38x.c rtc: remove redundant of_match_ptr() 2023-08-10 09:45:41 +02:00
rtc-as3722.c
rtc-asm9260.c rtc: asm9260: Convert to platform remove callback returning void 2023-03-17 23:03:17 +01:00
rtc-aspeed.c rtc: remove redundant of_match_ptr() 2023-08-10 09:45:41 +02:00
rtc-at91rm9200.c rtc: remove redundant of_match_ptr() 2023-08-10 09:45:41 +02:00
rtc-at91sam9.c rtc: at91sam9: fix OF node leak in probe() error path 2024-10-10 11:57:57 +02:00
rtc-au1xxx.c
rtc-bd70528.c
rtc-bq32k.c rtc: Switch i2c drivers back to use .probe() 2023-06-06 23:29:37 +02:00
rtc-bq4802.c
rtc-brcmstb-waketimer.c rtc: brcmstb-waketimer: support level alarm_irq 2023-11-20 11:59:30 +01:00
rtc-cadence.c rtc: cadence: Convert to platform remove callback returning void 2023-03-17 23:03:17 +01:00
rtc-cmos.c rtc: cmos: use spin_lock_irqsave in cmos_interrupt 2025-07-10 16:03:03 +02:00
rtc-core.h
rtc-cpcap.c
rtc-cros-ec.c rtc: cros-ec: Detect and report supported alarm window size 2023-08-27 23:50:22 +02:00
rtc-da9052.c
rtc-da9055.c
rtc-da9063.c rtc: da9063: Mark the alarm IRQ as a wake IRQ 2023-08-17 01:09:50 +02:00
rtc-digicolor.c
rtc-ds1216.c
rtc-ds1286.c
rtc-ds1302.c
rtc-ds1305.c rtc: ds1305: Report maximum alarm limit to rtc core 2023-08-27 23:50:22 +02:00
rtc-ds1307.c rtc: ds1307: stop disabling alarms on probe 2025-06-04 14:42:01 +02:00
rtc-ds1343.c
rtc-ds1347.c
rtc-ds1374.c rtc: Switch i2c drivers back to use .probe() 2023-06-06 23:29:37 +02:00
rtc-ds1390.c rtc: ds1390: mark OF related data as maybe unused 2023-03-17 23:23:22 +01:00
rtc-ds1511.c
rtc-ds1553.c
rtc-ds1672.c rtc: Switch i2c drivers back to use .probe() 2023-06-06 23:29:37 +02:00
rtc-ds1685.c rtc: ds1685: use EXPORT_SYMBOL_GPL for ds1685_rtc_poweroff 2023-08-02 11:18:22 -07:00
rtc-ds1742.c rtc: Explicitly include correct DT includes 2023-07-27 23:31:29 +02:00
rtc-ds2404.c rtc: ds2404: Convert to GPIO descriptors 2023-08-17 00:55:56 +02:00
rtc-ds3232.c rtc: Switch i2c drivers back to use .probe() 2023-06-06 23:29:37 +02:00
rtc-efi.c
rtc-em3027.c rtc: Switch i2c drivers back to use .probe() 2023-06-06 23:29:37 +02:00
rtc-ep93xx.c
rtc-fm3130.c rtc: Switch i2c drivers back to use .probe() 2023-06-06 23:29:37 +02:00
rtc-fsl-ftm-alarm.c rtc: Explicitly include correct DT includes 2023-07-27 23:31:29 +02:00
rtc-ftrtc010.c rtc: ftrtc010: Convert to platform remove callback returning void 2023-03-17 23:03:17 +01:00
rtc-gamecube.c
rtc-generic.c
rtc-goldfish.c
rtc-hid-sensor-time.c rtc: hid-sensor-time: Convert to platform remove callback returning void 2023-03-17 23:03:17 +01:00
rtc-hym8563.c rtc: Switch i2c drivers back to use .probe() 2023-06-06 23:29:37 +02:00
rtc-imx-sc.c
rtc-imxdi.c
rtc-isl1208.c rtc: isl1208: Fix return value of nvmem callbacks 2024-08-03 08:54:29 +02:00
rtc-isl12022.c rtc: isl12022: implement support for the #clock-cells DT property 2023-08-16 01:27:01 +02:00
rtc-isl12026.c rtc: isl12026: Drop "_new" from probe callback name 2023-07-27 23:32:08 +02:00
rtc-jz4740.c rtc: jz4740: fix Wvoid-pointer-to-enum-cast warning 2023-08-16 01:32:08 +02:00
rtc-loongson.c rtc: loongson: Add missing alarm notifications for ACPI RTC events 2025-06-19 15:28:29 +02:00
rtc-lp8788.c
rtc-lpc24xx.c rtc: Explicitly include correct DT includes 2023-07-27 23:31:29 +02:00
rtc-lpc32xx.c
rtc-m41t80.c rtc: Explicitly include correct DT includes 2023-07-27 23:31:29 +02:00
rtc-m41t93.c
rtc-m41t94.c
rtc-m48t35.c
rtc-m48t59.c
rtc-m48t86.c rtc: m48t86: add DT support for m48t86 2023-08-28 00:01:51 +02:00
rtc-max6900.c rtc: Switch i2c drivers back to use .probe() 2023-06-06 23:29:37 +02:00
rtc-max6902.c
rtc-max6916.c
rtc-max8907.c
rtc-max8925.c
rtc-max8997.c
rtc-max8998.c
rtc-max77686.c rtc: max77686: Convert to platform remove callback returning void 2023-03-17 23:03:17 +01:00
rtc-mc13xxx.c rtc: mc13xxx: Convert to platform remove callback returning void 2023-03-17 23:03:17 +01:00
rtc-mc146818-lib.c rtc: Extend timeout for waiting for UIP to clear to 1s 2024-01-31 16:18:56 -08:00
rtc-mcp795.c
rtc-meson-vrtc.c rtc: meson-vrtc: Use ktime_get_real_ts64() to get the current time 2023-03-21 21:15:10 +01:00
rtc-meson.c
rtc-moxart.c
rtc-mpc5121.c rtc: Explicitly include correct DT includes 2023-07-27 23:31:29 +02:00
rtc-mpfs.c rtc: mpfs: Convert to platform remove callback returning void 2023-03-17 23:03:17 +01:00
rtc-msc313.c
rtc-msm6242.c
rtc-mt2712.c
rtc-mt6397.c rtc: Explicitly include correct DT includes 2023-07-27 23:31:29 +02:00
rtc-mt7622.c rtc: Explicitly include correct DT includes 2023-07-27 23:31:29 +02:00
rtc-mv.c
rtc-mxc_v2.c rtc: mxc_v2: Convert to platform remove callback returning void 2023-03-17 23:03:17 +01:00
rtc-mxc.c rtc: Explicitly include correct DT includes 2023-07-27 23:31:29 +02:00
rtc-nct3018y.c rtc: nct3018y: fix possible NULL dereference 2024-08-29 17:33:39 +02:00
rtc-ntxec.c
rtc-nxp-bbnsm.c
rtc-omap.c rtc: omap: Do not check for 0 return after calling platform_get_irq() 2023-08-17 01:17:34 +02:00
rtc-opal.c
rtc-optee.c
rtc-palmas.c rtc: palmas: Convert to platform remove callback returning void 2023-03-17 23:03:17 +01:00
rtc-pcap.c
rtc-pcf2123.c
rtc-pcf2127.c rtc: pcf2127: fix SPI command byte for PCF2131 2025-07-10 16:03:03 +02:00
rtc-pcf8523.c rtc: Switch i2c drivers back to use .probe() 2023-06-06 23:29:37 +02:00
rtc-pcf8563.c rtc: Switch i2c drivers back to use .probe() 2023-06-06 23:29:37 +02:00
rtc-pcf8583.c rtc: Switch i2c drivers back to use .probe() 2023-06-06 23:29:37 +02:00
rtc-pcf50633.c rtc: pcf50633: Convert to platform remove callback returning void 2023-03-17 23:03:18 +01:00
rtc-pcf85063.c rtc: pcf85063: do a SW reset if POR failed 2025-05-02 07:50:57 +02:00
rtc-pcf85363.c rtc: pcf85363: fix wrong mask/val parameters in regmap_update_bits call 2023-11-20 11:59:30 +01:00
rtc-pic32.c rtc: pic32: Convert to platform remove callback returning void 2023-03-17 23:03:18 +01:00
rtc-pl030.c
rtc-pl031.c
rtc-pm8xxx.c rtc: pm8xxx: Convert to platform remove callback returning void 2023-03-17 23:03:18 +01:00
rtc-ps3.c
rtc-pxa.c rtc: Explicitly include correct DT includes 2023-07-27 23:31:29 +02:00
rtc-r7301.c
rtc-r9701.c
rtc-rc5t583.c rtc: rc5t583: Convert to platform remove callback returning void 2023-03-17 23:03:18 +01:00
rtc-rc5t619.c
rtc-rk808.c
rtc-rp5c01.c
rtc-rs5c313.c
rtc-rs5c348.c
rtc-rs5c372.c rtc: rs5c372: fix Wvoid-pointer-to-enum-cast warning 2023-08-16 01:32:08 +02:00
rtc-rtd119x.c rtc: rtd119x: Convert to platform remove callback returning void 2023-03-17 23:03:18 +01:00
rtc-rv3028.c rtc: Explicitly include correct DT includes 2023-07-27 23:31:29 +02:00
rtc-rv3029c2.c rtc: Switch i2c drivers back to use .probe() 2023-06-06 23:29:37 +02:00
rtc-rv3032.c rtc: rv3032: fix EERD location 2025-06-04 14:41:58 +02:00
rtc-rv8803.c rtc: rv8803: fix Wvoid-pointer-to-enum-cast warning 2023-08-16 01:32:08 +02:00
rtc-rx4581.c
rtc-rx6110.c rtc: Explicitly include correct DT includes 2023-07-27 23:31:29 +02:00
rtc-rx8010.c rtc: Switch i2c drivers back to use .probe() 2023-06-06 23:29:37 +02:00
rtc-rx8025.c rtc: Switch i2c drivers back to use .probe() 2023-06-06 23:29:37 +02:00
rtc-rx8581.c rtc: Explicitly include correct DT includes 2023-07-27 23:31:29 +02:00
rtc-rzn1.c rtc: rzn1: fix BCD to rtc_time conversion errors 2024-12-09 10:32:56 +01:00
rtc-s3c.c rtc: Explicitly include correct DT includes 2023-07-27 23:31:29 +02:00
rtc-s3c.h
rtc-s5m.c rtc: s5m: Drop S5M8763 support 2023-04-26 11:40:26 +01:00
rtc-s35390a.c rtc: Switch i2c drivers back to use .probe() 2023-06-06 23:29:37 +02:00
rtc-sa1100.c rtc: sa1100: Convert to platform remove callback returning void 2023-03-17 23:03:18 +01:00
rtc-sa1100.h
rtc-sc27xx.c
rtc-sd3078.c rtc: Switch i2c drivers back to use .probe() 2023-06-06 23:29:37 +02:00
rtc-sh.c rtc: sh: assign correct interrupts with DT 2025-06-19 15:28:28 +02:00
rtc-snvs.c
rtc-spear.c rtc: spear: Convert to platform remove callback returning void 2023-03-17 23:03:18 +01:00
rtc-st-lpc.c rtc: st-lpc: Use IRQF_NO_AUTOEN flag in request_irq() 2024-12-09 10:32:55 +01:00
rtc-starfire.c
rtc-stk17ta8.c
rtc-stm32.c rtc: stm32: Use NOIRQ_SYSTEM_SLEEP_PM_OPS() 2023-08-17 00:53:00 +02:00
rtc-stmp3xxx.c rtc: Explicitly include correct DT includes 2023-07-27 23:31:29 +02:00
rtc-sun4v.c
rtc-sun6i.c rtc: sun6i: remove unnecessary message 2023-09-06 01:26:04 +02:00
rtc-sunplus.c rtc: sunplus: Clean up redundant dev_err_probe() 2023-08-10 09:35:28 +02:00
rtc-sunxi.c rtc: Explicitly include correct DT includes 2023-07-27 23:31:29 +02:00
rtc-tegra.c rtc: tegra: Convert to platform remove callback returning void 2023-03-17 23:03:18 +01:00
rtc-test.c
rtc-ti-k3.c rtc: Explicitly include correct DT includes 2023-07-27 23:31:29 +02:00
rtc-tps6586x.c rtc: tps6586x: Report maximum alarm limit to rtc core 2023-08-27 23:50:22 +02:00
rtc-tps65910.c rtc: tps65910: Remove redundant dev_warn() and do not check for 0 return after calling platform_get_irq() 2023-08-17 01:17:34 +02:00
rtc-twl.c rtc: twl: remove unnecessary messages 2023-09-06 01:26:04 +02:00
rtc-vt8500.c rtc: vt8500: Convert to platform remove callback returning void 2023-03-17 23:03:18 +01:00
rtc-wilco-ec.c
rtc-wm831x.c
rtc-wm8350.c rtc: wm8350: remove unnecessary messages 2023-09-06 01:26:04 +02:00
rtc-x1205.c rtc: Switch i2c drivers back to use .probe() 2023-06-06 23:29:37 +02:00
rtc-xgene.c rtc: xgene: Convert to platform remove callback returning void 2023-03-17 23:03:18 +01:00
rtc-zynqmp.c rtc: zynqmp: Fix optional clock name property 2025-02-17 09:40:41 +01:00
sysfs.c