kernel/linux.git/drivers/watchdog, branch v5.15.212

watchdog: unregister PM notifier on watchdog unregister

2026-07-24T13:51:33+00:00

[ Upstream commit a298c7302ee9584a7a1ac1e8acbede8d98ab51a4 ] watchdog_register_device() registers wdd->pm_nb when WDOG_NO_PING_ON_SUSPEND is set, but watchdog_unregister_device() does not remove it. This leaves an embedded notifier block on the PM notifier chain after the watchdog device has been unregistered. A later suspend/resume notification can then call watchdog_pm_notifier() with a stale watchdog_device pointer, or at minimum after wdd->wd_data has been cleared by watchdog_dev_unregister(). Unregister the PM notifier before tearing down the watchdog device. Fixes: 60bcd91aafd2 ("watchdog: introduce watchdog_dev_suspend/resume") Signed-off-by: Yuho Choi Link: https://lore.kernel.org/r/20260601192005.1970805-1-dbgh9129@gmail.com Signed-off-by: Guenter Roeck Signed-off-by: Sasha Levin

watchdog: sprd_wdt: Remove redundant sprd_wdt_disable() on register failure

2026-07-24T13:51:28+00:00

[ Upstream commit 96b3cfc3b8ad0524d12fed1e08bc5df3ff345f64 ] The driver uses devm_add_action_or_reset() to register sprd_wdt_disable() as a managed cleanup action. When devm_watchdog_register_device() fails, the devm core will invoke the cleanup action automatically. The explicit sprd_wdt_disable() call in the error path is therefore redundant and results in adouble cleanup. Fixes: 78d9bfad2e89 ("watchdog: sprd_wdt: Convert to use device managed functions and other improvements") Signed-off-by: Felix Gu Reviewed-by: Guenter Roeck Reviewed-by: Baolin Wang Link: https://lore.kernel.org/r/20260223-sprd_wdt-v1-1-2e71f9a76ecb@gmail.com Signed-off-by: Guenter Roeck Signed-off-by: Sasha Levin

watchdog: sp5100_tco: Use EFCH MMIO for newer Hygon FCH

2026-07-24T13:51:28+00:00

[ Upstream commit 4f675f036cd5e9cfbe6df5f24f8338158af96a4b ] Commit 009637de1f65 ("watchdog: sp5100_tco: support Hygon FCH/SCH (Server Controller Hub)") added Hygon vendor matching to the efch layout selection, but newer Hygon 0x790b SMBus devices still need the efch_mmio path. The efch_mmio path enables EFCH_PM_DECODEEN_WDT_TMREN before probing the watchdog MMIO block. If firmware leaves that bit clear and the driver picks the legacy efch path instead, probe falls back to the alternate window and fails with "Watchdog hardware is disabled". Select efch_mmio for Hygon 0x790b devices with revision 0x51 or later, matching the equivalent AMD behavior and allowing the watchdog to initialize on those systems. Fixes: 009637de1f65 ("watchdog: sp5100_tco: support Hygon FCH/SCH (Server Controller Hub)") Signed-off-by: Yingjie Gao Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20260402071617.634563-2-gaoyingjie@uniontech.com Signed-off-by: Guenter Roeck Signed-off-by: Sasha Levin

fix it87_wdt early reboot by reporting running timer

2026-03-04T12:20:16+00:00

[ Upstream commit 88b2ab346436f799b99894a3e9518a3ffa344524 ] Some products, such as the Ugreen DXP4800 Plus NAS, ship with the it87 wdt enabled by the firmware and a broken BIOS option that does not allow to change the time or turn it off. As this makes installing Linux rather difficult, change the it87_wdt to report it running to the watchdog core. Signed-off-by: René Rebe Reviewed-by: Guenter Roeck Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck Signed-off-by: Sasha Levin

via_wdt: fix critical boot hang due to unnamed resource allocation

2026-01-19T12:09:47+00:00

[ Upstream commit 7aa31ee9ec92915926e74731378c009c9cc04928 ] The VIA watchdog driver uses allocate_resource() to reserve a MMIO region for the watchdog control register. However, the allocated resource was not given a name, which causes the kernel resource tree to contain an entry marked as "" under /proc/iomem on x86 platforms. During boot, this unnamed resource can lead to a critical hang because subsequent resource lookups and conflict checks fail to handle the invalid entry properly. Signed-off-by: Li Qiang Reviewed-by: Guenter Roeck Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck Signed-off-by: Sasha Levin

watchdog: wdat_wdt: Fix ACPI table leak in probe function

2026-01-19T12:09:30+00:00

[ Upstream commit 25c0b472eab8379683d4eef681185c104bed8ffd ] wdat_wdt_probe() calls acpi_get_table() to obtain the WDAT ACPI table but never calls acpi_put_table() on any paths. This causes a permanent ACPI table memory leak. Add a single cleanup path which calls acpi_put_table() to ensure the ACPI table is always released. Fixes: 058dfc767008 ("ACPI / watchdog: Add support for WDAT hardware watchdog") Suggested-by: Guenter Roeck Signed-off-by: Haotian Zhang Reviewed-by: Guenter Roeck Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck Signed-off-by: Sasha Levin

watchdog: wdat_wdt: Stop watchdog when uninstalling module

2026-01-19T12:09:30+00:00

[ Upstream commit 330415ebea81b65842e4cc6d2fd985c1b369e650 ] Test shows that wachdog still reboots machine after the module is removed. Use watchdog_stop_on_unregister to stop the watchdog on removing. Signed-off-by: Liu Xinpeng eviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/1650984810-6247-4-git-send-email-liuxp11@chinatelecom.cn Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck Stable-dep-of: 25c0b472eab8 ("watchdog: wdat_wdt: Fix ACPI table leak in probe function") Signed-off-by: Sasha Levin

watchdog: mpc8xxx_wdt: Reload the watchdog timer when enabling the watchdog

2025-10-19T14:21:34+00:00

[ Upstream commit 7dfd80f70ef00d871df5af7c391133f7ba61ad9b ] When the watchdog gets enabled with this driver, it leaves enough time for the core watchdog subsystem to start pinging it. But when the watchdog is already started by hardware or by the boot loader, little time remains before it fires and it happens that the core watchdog subsystem doesn't have time to start pinging it. Until commit 19ce9490aa84 ("watchdog: mpc8xxx: use the core worker function") pinging was managed by the driver itself and the watchdog was immediately pinged by setting the timer expiry to 0. So restore similar behaviour by pinging it when enabling it so that if it was already enabled the watchdog timer counter is reloaded. Fixes: 19ce9490aa84 ("watchdog: mpc8xxx: use the core worker function") Signed-off-by: Christophe Leroy Reviewed-by: Guenter Roeck Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck Signed-off-by: Sasha Levin

watchdog: iTCO_wdt: Report error if timeout configuration fails

2025-08-28T14:24:23+00:00

[ Upstream commit 40efc43eb7ffb5a4e2f998c13b8cfb555e671b92 ] The driver probes with the invalid timeout value when 'iTCO_wdt_set_timeout()' fails, as its return value is not checked. In this case, when executing "wdctl", we may get: Device: /dev/watchdog0 Timeout: 30 seconds Timeleft: 613 seconds The timeout value is the value of "heartbeat" or "WATCHDOG_TIMEOUT", and the timeleft value is calculated from the register value we actually read (0xffff) by masking with 0x3ff and converting ticks to seconds (* 6 / 10). Add error handling to return the failure code if 'iTCO_wdt_set_timeout()' fails, ensuring the driver probe fails and prevents invalid operation. Signed-off-by: Ziyan Fu Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20250704073518.7838-1-13281011316@163.com Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck Signed-off-by: Sasha Levin

watchdog: dw_wdt: Fix default timeout

2025-08-28T14:24:23+00:00

[ Upstream commit ac3dbb91e0167d017f44701dd51c1efe30d0c256 ] The Synopsys Watchdog driver sets the default timeout to 30 seconds, but on some devices this is not a valid timeout. E.g. on RK3588 the actual timeout being used is 44 seconds instead. Once the watchdog is started the value is updated accordingly, but it would be better to expose a sensible timeout to userspace without the need to first start the watchdog. Signed-off-by: Sebastian Reichel Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20250717-dw-wdt-fix-initial-timeout-v1-1-86dc864d48dd@kernel.org Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck Signed-off-by: Sasha Levin