Some systems, e.g. chromebooks, don't have a physical SysRq key. Patch 3/6 allows configuring which key acts as SysRq. If unconfigured, the default KEY_SYSRQ is used. The sysrq_key_table has effectively run out of free slots. Patch 4/6 extends the said table to accommodate capital letters, so on top of 0-9 and 'a'-'z' 'A'-'Z' are added. Userland might want to be able to signal a specifically named process with a specific signal as a result of some SysRq action. Patch 5/6 adds such a capability. The name of the signalled process, the name of the signal to be delivered to it and, optionally, the expected name of the target process parent are configured. Once configured, the action is available under Alt-Shift-SysRq-s. Userland might also want to be able to execute a compound action, e.g. the famous "Raising Elephants Is So Utterly Boring", or, say, 'w' (show blocked tasks), followed by 's' (sync), followed by 1000 ms delay and then followed by 'c' (crash). Patch 6/6 adds such a capability. The (short) names of component actions are specified with a string. Optional delays between actions are specified with a colon and the amount of milliseconds, e.g. "reis:1000ub" or "ws:1000c". Once configured, the action is available under Alt-Shift-SysRq-c. While at it, remove unused linux,sysrq-reset-seq handling code and the associated binding (patches 1/6 and 2/6). Andrzej Pietrasiewicz (6): tty/sysrq: Remove linux,sysrq-reset-seq dt-bindings: input: Remove linux,sysrq-reset-seq binding tty/sysrq: Allow configurable SysRq key tty/sysrq: Extend the sysrq_key_table to cover capital letters tty/sysrq: Add configurable handler to signal a process tty/sysrq: Add configurable handler to execute a compound action .../devicetree/bindings/input/input-reset.txt | 33 --- drivers/tty/sysrq.c | 268 ++++++++++++++++-- 2 files changed, 238 insertions(+), 63 deletions(-) delete mode 100644 Documentation/devicetree/bindings/input/input-reset.txt base-commit: 2ef96a5bb12be62ef75b5828c0aab838ebb29cb8 -- 2.17.1
