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2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman
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 <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-10locking/lockdep: Avoid creating redundant linksPeter Zijlstra
Two boots + a make defconfig, the first didn't have the redundant bit in, the second did: lock-classes: 1168 1169 [max: 8191] direct dependencies: 7688 5812 [max: 32768] indirect dependencies: 25492 25937 all direct dependencies: 220113 217512 dependency chains: 9005 9008 [max: 65536] dependency chain hlocks: 34450 34366 [max: 327680] in-hardirq chains: 55 51 in-softirq chains: 371 378 in-process chains: 8579 8579 stack-trace entries: 108073 88474 [max: 524288] combined max dependencies: 178738560 169094640 max locking depth: 15 15 max bfs queue depth: 320 329 cyclic checks: 9123 9190 redundant checks: 5046 redundant links: 1828 find-mask forwards checks: 2564 2599 find-mask backwards checks: 39521 39789 So it saves nearly 2k links and a fair chunk of stack-trace entries, but as expected, makes no real difference on the indirect dependencies. At the same time, you see the max BFS depth increase, which is also expected, although it could easily be boot variance -- these numbers are not entirely stable between boots. The down side is that the cycles in the graph become larger and thus the reports harder to read. XXX: do we want this as a CONFIG variable, implied by LOCKDEP_SMALL? Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Byungchul Park <byungchul.park@lge.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@kernel.org> Cc: Nikolay Borisov <nborisov@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: akpm@linux-foundation.org Cc: boqun.feng@gmail.com Cc: iamjoonsoo.kim@lge.com Cc: kernel-team@lge.com Cc: kirill@shutemov.name Cc: npiggin@gmail.com Cc: walken@google.com Link: http://lkml.kernel.org/r/20170303091338.GH6536@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-12-24Replace <asm/uaccess.h> with <linux/uaccess.h> globallyLinus Torvalds
This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>' sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-23lockdep: Fix lock_chain::base sizePeter Zijlstra
lock_chain::base is used to store an index into the chain_hlocks[] array, however that array contains more elements than can be indexed using the u16. Change the lock_chain structure to use a bitfield to encode the data it needs and add BUILD_BUG_ON() assertions to check the fields are wide enough. Also, for DEBUG_LOCKDEP, assert that we don't run out of elements of that array; as that would wreck the collision detectoring. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alfredo Alvarez Fernandez <alfredoalvarezfernandez@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sedat Dilek <sedat.dilek@gmail.com> Cc: Theodore Ts'o <tytso@mit.edu> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160330093659.GS3408@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-11-23treewide: Remove old email addressPeter Zijlstra
There were still a number of references to my old Red Hat email address in the kernel source. Remove these while keeping the Red Hat copyright notices intact. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-07lockdep: Fix a race between /proc/lock_stat and module unloadPeter Zijlstra
The lock_class iteration of /proc/lock_stat is not serialized against the lockdep_free_key_range() call from module unload. Therefore it can happen that we find a class of which ->name/->key are no longer valid. There is a further bug in zap_class() that left ->name dangling. Cure this. Use RCU_INIT_POINTER() because NULL. Since lockdep_free_key_range() is rcu_sched serialized, we can read both ->name and ->key under rcu_read_lock_sched() (preempt-disable) and be assured that if we observe a !NULL value it stays safe to use for as long as we hold that lock. If we observe both NULL, skip the entry. Reported-by: Jerome Marchand <jmarchan@redhat.com> Tested-by: Jerome Marchand <jmarchan@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20150602105013.GS3644@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-11-11lockdep/proc: Fix lock-time avg computationPeter Zijlstra
> kernel/locking/lockdep_proc.c: In function 'seq_lock_time': > >> kernel/locking/lockdep_proc.c:424:23: warning: comparison of distinct pointer types lacks a cast [enabled by default] > > 418 static void seq_lock_time(struct seq_file *m, struct lock_time *lt) > 419 { > 420 seq_printf(m, "%14lu", lt->nr); > 421 seq_time(m, lt->min); > 422 seq_time(m, lt->max); > 423 seq_time(m, lt->total); > > 424 seq_time(m, lt->nr ? do_div(lt->total, lt->nr) : 0); > 425 } My compiler refuses to actually say that; but it looks wrong in that do_div() returns the remainder, not the divisor. Reported-by: Fengguang Wu <fengguang.wu@intel.com> Tested-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Davidlohr Bueso <davidlohr@hp.com> Link: http://lkml.kernel.org/r/20131106164230.GE16117@laptop.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-11-06locking: Move the lockdep code to kernel/locking/Peter Zijlstra
Suggested-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-wl7s3tta5isufzfguc23et06@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>