kernel/linux.git/Documentation/admin-guide/sysrq.rst, branch linux-7.1.y

Documentation: remove :kyb: tags

2024-12-11T16:07:39+00:00

:kyb: is an extra markup that we should avoid when we can. It worsens the plain-text reading experience and adds very little value to rendered views. Remove all :kbd: tags from Documentation/* Signed-off-by: Cengiz Can Signed-off-by: Jonathan Corbet Link: https://lore.kernel.org/r/20241202090514.1716-1-cengiz@kernel.wtf

tty/sysrq: Replay kernel log messages on consoles via sysrq

2024-04-11T12:22:52+00:00

When terminal is unresponsive, one cannot use dmesg to view the printk ring buffer messages. Also, syslog services may be disabled, especially on embedded systems, to check the messages after a reboot. In this scenario, replay the messages in printk ring buffer on consoles via sysrq by pressing sysrq+R. The console loglevel will determine which all kernel log messages are displayed. The messages will be displayed only when console_trylock() succeeds. Users could repeat the sysrq key when it fails. If the owner of console subsystem lock is stuck, repeating the key won't work. Suggested-by: Petr Mladek Signed-off-by: Shimoyashiki Taichi Reviewed-by: John Ogness Signed-off-by: Sreenath Vijayan Link: https://lore.kernel.org/r/cc3b9b1aae60a236c6aed1dc7b0ffa2c7cd1f183.1710220326.git.sreenath.vijayan@sony.com Signed-off-by: Greg Kroah-Hartman

/proc/sysrq-trigger: accept multiple keys at once

2023-11-25T07:23:16+00:00

This way we can do: `echo _reisub > /proc/sysrq-trigger` Instead of: `for i in r e i s u b; do echo "$i" > /proc/sysrq-trigger; done;` This can be very useful when trying to execute sysrq combo remotely or from userspace. When sending keys in multiple separate writes, userspace (eg. bash or ssh) can be killed before whole combo is completed. Therefore putting all keys in single write is more robust approach. Signed-off-by: Tomas Mudrunka Reviewed-by: Jiri Slaby Link: https://lore.kernel.org/r/20231120111451.527952-1-tomas.mudrunka@gmail.com Signed-off-by: Greg Kroah-Hartman

Documentation: admin-guide: correct spelling

2023-02-02T18:04:42+00:00

Correct spelling problems for Documentation/admin-guide/ as reported by codespell. Signed-off-by: Randy Dunlap Reviewed-by: Mukesh Ojha Cc: Tejun Heo Cc: Zefan Li Cc: Johannes Weiner Cc: cgroups@vger.kernel.org Cc: Alasdair Kergon Cc: Mike Snitzer Cc: dm-devel@redhat.com Cc: Mauro Carvalho Chehab Cc: linux-media@vger.kernel.org Cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/20230129231053.20863-2-rdunlap@infradead.org Signed-off-by: Jonathan Corbet

Documentation: sysrq: convert to third person

2021-07-15T12:33:44+00:00

Two parts of the sysrq documentation have sentences written from a first person's point of view. Documentation is generally written from a third person's view in a formal way. Convert those senteces to be less personal and generic. Signed-off-by: Cengiz Can Link: https://lore.kernel.org/r/20210629141508.52229-1-cengiz@kernel.wtf Signed-off-by: Jonathan Corbet

Documentation: sysrq: update description about sysrq crash

2021-03-15T20:23:21+00:00

After commit 8341f2f222d7 ("sysrq: Use panic() to force a crash"), a crash was not generated by dereferencing a NULL pointer anymore. Let's update documentation as well to make it less misleading. Signed-off-by: Gao Xiang Cc: Matthias Kaehlcke Cc: Greg Kroah-Hartman Cc: Jonathan Corbet Cc: Zefan Li Link: https://lore.kernel.org/r/20210309191550.3955601-1-hsiangkao@redhat.com Signed-off-by: Jonathan Corbet

tty/sysrq: Extend the sysrq_key_table to cover capital letters

2020-10-02T12:56:06+00:00

All slots in sysrq_key_table[] are either used, reserved or at least commented with their intended use. This patch adds capital letter versions available, which means adding 26 more entries. For already existing SysRq operations the user presses Alt-SysRq-, and for the newly added ones Alt-Shift-SysRq-. Signed-off-by: Andrzej Pietrasiewicz Acked-by: Daniel Vetter Link: https://lore.kernel.org/r/20200818112825.6445-2-andrzej.p@collabora.com Signed-off-by: Greg Kroah-Hartman

tty/sysrq: constify the sysrq API

2020-05-15T12:53:19+00:00

The user is not supposed to thinker with the underlying sysrq_key_op. Make that explicit by adding a handful of const notations. Cc: Greg Kroah-Hartman Cc: Jiri Slaby Cc: linux-kernel@vger.kernel.org Signed-off-by: Emil Velikov Link: https://lore.kernel.org/r/20200513214351.2138580-2-emil.l.velikov@gmail.com Signed-off-by: Greg Kroah-Hartman

Documentation: sysrq: fix RST formatting

2020-04-07T19:32:15+00:00

"On x86" and "On SPARC" are now definition list terms, like "On PowerPC", "On other", and "On all". The Credits list is now a bulleted list, like lots of Credits lists in other files. This prevents the list from becoming a single long, unpunctuated sentence in the generated documentation. I also did a couple of other tiny readability improvements to the "How do I use the magic SysRq key?" section while I was there. Signed-off-by: Alyssa Ross Link: https://lore.kernel.org/r/20200403170701.10852-1-hi@alyssa.is Signed-off-by: Jonathan Corbet

Documentation: sysrq: don't recommend 'S' 'U' before 'B'

2019-09-06T14:42:52+00:00

This advice is obsolete and slightly harmful for filesystems from this millenium: any modern filesystem can handle unexpected crashes without requiring fsck -- and on the other hand, trying to write to the disk when the kernel is in a bad state risks introducing corruption. For ext2, any unsafe shutdown meant widespread breakage, but it's no longer a reasonable filesystem for any non-special use. Signed-off-by: Adam Borowski Signed-off-by: Jonathan Corbet