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2025-04-17docs: ABI: replace mcroce@microsoft.com with new Meta addressAhmad Fatoum
The Microsoft email address is bouncing: 550 5.4.1 Recipient address rejected: Access denied. So let's replace it with Matteo's current mail address. Link: https://lkml.kernel.org/r/20250414-fix-mcroce-mail-bounce-v3-1-0aed2d71f3d7@pengutronix.de Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de> Acked-by: Matteo Croce <teknoraver@meta.com> Link: https://lore.kernel.org/all/BYAPR15MB2504E4B02DFFB1E55871955DA1062@BYAPR15MB2504.namprd15.prod.outlook.com/ Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Matteo Croce <teknoraver@meta.com> Cc: Sascha Hauer <kernel@pengutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-03-16reboot: add support for configuring emergency hardware protection actionAhmad Fatoum
We currently leave the decision of whether to shutdown or reboot to protect hardware in an emergency situation to the individual drivers. This works out in some cases, where the driver detecting the critical failure has inside knowledge: It binds to the system management controller for example or is guided by hardware description that defines what to do. In the general case, however, the driver detecting the issue can't know what the appropriate course of action is and shouldn't be dictating the policy of dealing with it. Therefore, add a global hw_protection toggle that allows the user to specify whether shutdown or reboot should be the default action when the driver doesn't set policy. This introduces no functional change yet as hw_protection_trigger() has no callers, but these will be added in subsequent commits. [arnd@arndb.de: hide unused hw_protection_attr] Link: https://lkml.kernel.org/r/20250224141849.1546019-1-arnd@kernel.org Link: https://lkml.kernel.org/r/20250217-hw_protection-reboot-v3-7-e1c09b090c0c@pengutronix.de Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de> Reviewed-by: Tzung-Bi Shih <tzungbi@kernel.org> Cc: Benson Leung <bleung@chromium.org> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Fabio Estevam <festevam@denx.de> Cc: Guenter Roeck <groeck@chromium.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Girdwood <lgirdwood@gmail.com> Cc: Lukasz Luba <lukasz.luba@arm.com> Cc: Mark Brown <broonie@kernel.org> Cc: Matteo Croce <teknoraver@meta.com> Cc: Matti Vaittinen <mazziesaccount@gmail.com> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Rob Herring (Arm) <robh@kernel.org> Cc: Rui Zhang <rui.zhang@intel.com> Cc: Sascha Hauer <kernel@pengutronix.de> Cc: "Serge E. Hallyn" <serge@hallyn.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2020-12-15reboot: allow to specify reboot mode via sysfsMatteo Croce
The kernel cmdline reboot= option offers some sort of control on how the reboot is issued. We don't always know in advance what type of reboot to perform. Sometimes a warm reboot is preferred to persist certain memory regions across the reboot. Others a cold one is needed to apply a future system update that makes a memory memory model change, like changing the base page size or resizing a persistent memory region. Or simply we want to enable reboot_force because we noticed that something bad happened. Add handles in sysfs to allow setting these reboot options, so they can be changed when the system is booted, other than at boot time. The handlers are under <sysfs>/kernel/reboot, can be read to get the current configuration and written to alter it. # cd /sys/kernel/reboot/ # grep . * cpu:0 force:0 mode:cold type:acpi # echo 2 >cpu # echo yes >force # echo soft >mode # echo bios >type # grep . * cpu:2 force:1 mode:soft type:bios Before setting anything, check for CAP_SYS_BOOT capability, so it's possible to allow an unpriviledged process to change these settings simply by relaxing the handles permissions, without opening them to the world. [natechancellor@gmail.com: fix variable assignments in type_store] Link: https://lkml.kernel.org/r/20201112035023.974748-1-natechancellor@gmail.com Link: https://github.com/ClangBuiltLinux/linux/issues/1197 Link: https://lkml.kernel.org/r/20201110202746.9690-1-mcroce@linux.microsoft.com Signed-off-by: Matteo Croce <mcroce@microsoft.com> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Kees Cook <keescook@chromium.org> Cc: Tyler Hicks <tyhicks@linux.microsoft.com> Cc: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>