kernel/linux.git/drivers/tty/vt/selection.c, branch v4.14.85

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

2017-11-02T10:10:55+00:00

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

vt: make mouse selection of non-ASCII consistent

2017-04-11T19:39:15+00:00

For some reason a handful of ISO-8859-1 symbols are excluded from "word chars" while the vast majority of Unicode is hard-coded as included, even when inappropriate (we really would want to _not_ select line-drawing/etc). Those symbols are: ¡¢£¤¥¦§¨©ª«¬®¯°±²³´µ¶·¸¹º»¼½¾¿×÷ Thus, let's not special-case any non-ASCII anymore. Attempts to set these via ioctl will be silently ignored. As an extra bonus, we debloat the kernel by 128 bytes. Signed-off-by: Adam Borowski Signed-off-by: Greg Kroah-Hartman

vt: set mouse selection word-chars to gpm's default

2017-04-11T19:39:14+00:00

Since forever, gpm was this code's only user, and it overrides the table on start so the default was never seen -- until Bill Allombert's "consolation" came in. The in-kernel set is "A-Za-z0-9_" which fails to catch typical file names, etc. Let's change this to gpm's conservative default, ie "-A-Za-z0-9_./"; most terminals include more, for example xfce4-terminal has "-A-Za-z0-9,./?%&#:_=+@~". There's some discussion at https://bugs.debian.org/846587 Signed-off-by: Adam Borowski Signed-off-by: Greg Kroah-Hartman

Replace with globally

2016-12-24T19:46:01+00:00

This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*' sed -i -e "s!$PATT!#include !" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro Signed-off-by: Linus Torvalds

tty: Replace TTY_THROTTLED bit tests with tty_throttled()

2016-04-30T16:26:55+00:00

Abstract TTY_THROTTLED bit tests with tty_throttled(). Signed-off-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman

tty: Prepare for destroying line discipline on hangup

2016-01-27T23:01:44+00:00

tty file_operations (read/write/ioctl) wait for the ldisc reference indefinitely (until ldisc lifetime events, such as hangup or TIOCSETD, finish). Since hangup now destroys the ldisc and does not instance another copy, file_operations must now be prepared to receive a NULL ldisc reference from tty_ldisc_ref_wait(): CPU 0 CPU 1 ----- ----- (*f_op->read)() => tty_read() __tty_hangup() ... f_op = &hung_up_tty_fops; ... tty_ldisc_hangup() tty_ldisc_lock() tty_ldisc_kill() tty->ldisc = NULL tty_ldisc_unlock() ld = tty_ldisc_ref_wait() /* ld == NULL */ Instead, the action taken now is to return the same value as if the tty had been hungup a moment earlier: CPU 0 CPU 1 ----- ----- __tty_hangup() ... f_op = &hung_up_tty_fops; (*f_op->read)() => hung_up_tty_read() return 0; ... tty_ldisc_hangup() tty_ldisc_lock() tty_ldisc_kill() tty->ldisc = NULL tty_ldisc_unlock() Signed-off-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman

tty: vt: Fix !TASK_RUNNING diagnostic warning from paste_selection()

2015-07-24T01:08:29+00:00

Pasting text with gpm on a VC produced warning [1]. Reset task state to TASK_RUNNING in the paste_selection() loop, if the loop did not sleep. [1] WARNING: CPU: 6 PID: 1960 at /home/peter/src/kernels/mainline/kernel/sched/core.c:7286 __might_sleep+0x7f/0x90() do not call blocking ops when !TASK_RUNNING; state=1 set at [] paste_selection+0x9e/0x1a0 Modules linked in: btrfs xor raid6_pq ufs qnx4 hfsplus hfs minix ntfs msdos jfs xfs libcrc32c ..... CPU: 6 PID: 1960 Comm: gpm Not tainted 4.1.0-rc7+tty-xeon+debug #rc7+tty Hardware name: Dell Inc. Precision WorkStation T5400 /0RW203, BIOS A11 04/30/2012 ffffffff81c9c0a0 ffff8802b0fd3ac8 ffffffff8185778a 0000000000000001 ffff8802b0fd3b18 ffff8802b0fd3b08 ffffffff8108039a ffffffff82ae8510 ffffffff81c9ce00 0000000000000015 0000000000000000 0000000000000000 Call Trace: [] dump_stack+0x4f/0x7b [] warn_slowpath_common+0x8a/0xc0 [] warn_slowpath_fmt+0x46/0x50 [] ? __lock_acquire+0xe2d/0x13a0 [] ? paste_selection+0x9e/0x1a0 [] ? paste_selection+0x9e/0x1a0 [] __might_sleep+0x7f/0x90 [] down_read+0x2a/0xa0 [] ? sched_clock_cpu+0xb8/0xe0 [] n_tty_receive_buf_common+0x4c/0xba0 [] ? mark_held_locks+0x75/0xa0 [] ? _raw_spin_unlock_irqrestore+0x65/0x80 [] ? get_parent_ip+0x11/0x50 [] n_tty_receive_buf2+0x14/0x20 [] paste_selection+0x157/0x1a0 [] ? wake_up_state+0x20/0x20 [] tioclinux+0xb8/0x2c0 [] vt_ioctl+0xaee/0x11a0 [] ? sched_clock_local+0x25/0x90 [] ? vtime_account_user+0x91/0xa0 [] tty_ioctl+0x20c/0xe20 [] ? vtime_account_user+0x91/0xa0 [] ? get_parent_ip+0x11/0x50 [] ? preempt_count_sub+0x49/0x50 [] ? context_tracking_exit+0x5c/0x290 [] ? context_tracking_exit+0x5c/0x290 [] do_vfs_ioctl+0x318/0x570 [] ? trace_hardirqs_on+0xd/0x10 [] ? trace_hardirqs_on_caller+0x115/0x1e0 [] ? __fget_light+0x6c/0xa0 [] SyS_ioctl+0x81/0xa0 [] system_call_fastpath+0x16/0x7a Signed-off-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman

tty: Fix unsafe vt paste_selection()

2013-07-23T23:47:10+00:00

Convert the tty_buffer_flush() exclusion mechanism to a public interface - tty_buffer_lock/unlock_exclusive() - and use the interface to safely write the paste selection to the line discipline. Signed-off-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman

tty: Make ldisc input flow control concurrency-friendly

2013-07-23T23:42:59+00:00

Although line discipline receiving is single-producer/single-consumer, using tty->receive_room to manage flow control creates unnecessary critical regions requiring additional lock use. Instead, introduce the optional .receive_buf2() ldisc method which returns the # of bytes actually received. Serialization is guaranteed by the caller. In turn, the line discipline should schedule the buffer work item whenever space becomes available; ie., when there is room to receive data and receive_room() previously returned 0 (the buffer work item stops processing if receive_buf2() returns 0). Note the 'no room' state need not be atomic despite concurrent use by two threads because only the buffer work thread can set the state and only the read() thread can clear the state. Add n_tty_receive_buf2() as the receive_buf2() method for N_TTY. Provide a public helper function, tty_ldisc_receive_buf(), to use when directly accessing the receive_buf() methods. Line disciplines not using input flow control can continue to set tty->receive_room to a fixed value and only provide the receive_buf() method. Signed-off-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman

TTY: vt, fix paste_selection ldisc handling

2012-10-22T23:50:53+00:00

There used to be a single tty_ldisc_ref_wait. But then, when a big-tty-mutex (BTM) was introduced, it has to be tty_ldisc_ref + tty_unlock + tty_ldisc_ref_wait + tty_lock. Later, BTM was removed from that path and tty_ldisc_ref + tty_ldisc_ref_wait remained there. But it makes no sense now. So leave there only tty_ldisc_ref_wait. And when we have a reference to an ldisc, actually use it in the loop. Otherwise it may be racy. Signed-off-by: Jiri Slaby Acked-by: Alan Cox Signed-off-by: Greg Kroah-Hartman