kernel/drivers/tty/sysrq.c, branch linux-5.1.y

sysrq: Remove duplicated sysrq message

2019-01-22T12:46:53Z

The commit 97f5f0cd8cd0a0544 ("Input: implement SysRq as a separate input handler") added pr_fmt() definition. It caused a duplicated message prefix in the sysrq header messages, for example: [ 177.053931] sysrq: SysRq : Show backtrace of all active CPUs [ 742.864776] sysrq: SysRq : HELP : loglevel(0-9) reboot(b) crash(c) Fixes: 97f5f0cd8cd0a05 ("Input: implement SysRq as a separate input handler") Signed-off-by: Petr Mladek Reviewed-by: Sergey Senozhatsky Signed-off-by: Greg Kroah-Hartman

sysrq: Restore original console_loglevel when sysrq disabled

2019-01-22T12:46:53Z

The sysrq header line is printed with an increased loglevel to provide users some positive feedback. The original loglevel is not restored when the sysrq operation is disabled. This bug was introduced in 2.6.12 (pre-git-history) by the commit ("Allow admin to enable only some of the Magic-Sysrq functions"). Signed-off-by: Petr Mladek Reviewed-by: Sergey Senozhatsky Reviewed-by: Steven Rostedt (VMware) Signed-off-by: Greg Kroah-Hartman

tty/sysrq: Do not call sync directly from sysrq_do_reset()

2018-12-05T11:02:12Z

sysrq_do_reset() is called in softirq context, so it cannot call sync() directly. Instead, call orderly_reboot(), which creates a work item to run /sbin/reboot, or do emergency_sync and restart if the command fails. Signed-off-by: Mark Tomlinson Signed-off-by: Greg Kroah-Hartman

sysrq: Use panic() to force a crash

2018-11-27T10:16:35Z

sysrq_handle_crash() currently forces a crash by dereferencing a NULL pointer, which is undefined behavior in C. Just call panic() instead, which is simpler and doesn't depend on compiler specific handling of the undefined behavior. Remove the comment on why the RCU lock needs to be released, it isn't accurate anymore since the crash now isn't handled by the page fault handler (for reference: the comment was added by commit 984cf355aeaa ("sysrq: Fix warning in sysrq generated crash.")). Releasing the lock is still good practice though. Suggested-by: Greg Kroah-Hartman Signed-off-by: Matthias Kaehlcke Signed-off-by: Greg Kroah-Hartman

tty/sysrq: add of_node_put()

2018-11-27T10:16:35Z

of_find_node_by_path() acquires a reference to the node returned by it and that reference needs to be dropped by its caller. bl_idle_init() doesn't do that, so fix it. Signed-off-by: Yangtao Li Signed-off-by: Greg Kroah-Hartman

signal: send_sig_all no longer needs SEND_SIG_FORCED

2018-09-11T19:19:07Z

Now that send_signal always delivers SEND_SIG_PRIV signals to a pid namespace init it is no longer necessary to use SEND_SIG_FORCED when calling do_send_sig_info to ensure that pid namespace inits are signaled and possibly killed. Using SEND_SIG_PRIV is sufficient. So use SEND_SIG_PRIV so that userspace when it receives a SIGTERM can tell that the kernel sent the signal and not some random userspace application. Fixes: b82c32872db2 ("sysrq: use SEND_SIG_FORCED instead of force_sig()") Reviewed-by: Thomas Gleixner Signed-off-by: "Eric W. Biederman"

signal: Pass pid type into do_send_sig_info

2018-07-21T17:57:35Z

This passes the information we already have at the call sight into do_send_sig_info. Ultimately allowing for better handling of signals sent to a group of processes during fork. Signed-off-by: "Eric W. Biederman"

fs: add ksys_sync() helper; remove in-kernel calls to sys_sync()

2018-04-02T18:16:05Z

Using this helper allows us to avoid the in-kernel calls to the sys_sync() syscall. The ksys_ prefix denotes that this function is meant as a drop-in replacement for the syscall. In particular, it uses the same calling convention as sys_sync(). This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Cc: Alexander Viro Signed-off-by: Dominik Brodowski

Merge tag 'tty-4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

2017-11-14T05:05:31Z

Pull tty/serial updates from Greg KH: "Here is the big tty/serial driver pull request for 4.15-rc1. Lots of serial driver updates in here, some small vt cleanups, and a raft of SPDX and license boilerplate cleanups, messing up the diffstat a bit. Nothing major, with no realy functional changes except better hardware support for some platforms. All of these have been in linux-next for a while with no reported issues" * tag 'tty-4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (110 commits) tty: ehv_bytechan: fix spelling mistake tty: serial: meson: allow baud-rates lower than 9600 serial: 8250_fintek: Fix crash with baud rate B0 serial: 8250_fintek: Disable delays for ports != 0 serial: 8250_fintek: Return -EINVAL on invalid configuration tty: Remove redundant license text tty: serdev: Remove redundant license text tty: hvc: Remove redundant license text tty: serial: Remove redundant license text tty: add SPDX identifiers to all remaining files in drivers/tty/ tty: serial: jsm: remove redundant pointer ts tty: serial: jsm: add space before the open parenthesis '(' tty: serial: jsm: fix coding style tty: serial: jsm: delete space between function name and '(' tty: serial: jsm: add blank line after declarations tty: serial: jsm: change the type of local variable tty: serial: imx: remove dead code imx_dma_rxint tty: serial: imx: disable ageing timer interrupt if dma in use serial: 8250: fix potential deadlock in rs485-mode serial: m32r_sio: Drop redundant .data assignment ...

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02T10:10:55Z

Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman