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2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman1-0/+1
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>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar1-0/+1
<linux/sched/idle.h> We are going to split <linux/sched/idle.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/idle.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-20x86/cpu: Add workaround for MONITOR instruction erratum on Goldmont based CPUsPeter Zijlstra1-1/+1
Monitored cached line may not wake up from mwait on certain Goldmont based CPUs. This patch will avoid calling current_set_polling_and_test() and thereby not set the TIF_ flag. The result is that we'll always send IPIs for wakeups. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Len Brown <lenb@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1468867270-18493-1-git-send-email-jacob.jun.pan@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-30x86/cpufeature: Carve out X86_FEATURE_*Borislav Petkov1-0/+2
Move them to a separate header and have the following dependency: x86/cpufeatures.h <- x86/processor.h <- x86/cpufeature.h This makes it easier to use the header in asm code and not include the whole cpufeature.h and add guards for asm. Suggested-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.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/1453842730-28463-5-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-22x86/asm: Add MONITORX/MWAITX instruction supportHuang Rui1-0/+45
AMD Carrizo processors (Family 15h, Models 60h-6fh) added a new feature called MWAITX (MWAIT with extensions) as an extension to MONITOR/MWAIT. This new instruction controls a configurable timer which causes the core to exit wait state on timer expiration, in addition to "normal" MWAIT condition of reading from a monitored VA. Compared to MONITOR/MWAIT, there are minor differences in opcode and input parameters: MWAITX ECX[1]: enable timer if set MWAITX EBX[31:0]: max wait time expressed in SW P0 clocks == TSC. The software P0 frequency is the same as the TSC frequency. MWAIT MWAITX opcode 0f 01 c9 | 0f 01 fb ECX[0] value of RFLAGS.IF seen by instruction ECX[1] unused/#GP if set | enable timer if set ECX[31:2] unused/#GP if set EAX unused (reserve for hint) EBX[31:0] unused | max wait time (SW P0 == TSC) MONITOR MONITORX opcode 0f 01 c8 | 0f 01 fa EAX (logical) address to monitor ECX #GP if not zero Max timeout = EBX/(TSC frequency) Signed-off-by: Huang Rui <ray.huang@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Aaron Lu <aaron.lu@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andreas Herrmann <herrmann.der.user@gmail.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dirk Brandewie <dirk.j.brandewie@intel.com> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Len Brown <lenb@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <bitbucket@online.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rjw@rjwysocki.net> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Li <tony.li@amd.com> Link: http://lkml.kernel.org/r/1439201994-28067-3-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-16sched/idle/x86: Restore mwait_idle() to fix boot hangs, to improve power ↵Len Brown1-0/+8
savings and to improve performance In Linux-3.9 we removed the mwait_idle() loop: 69fb3676df33 ("x86 idle: remove mwait_idle() and "idle=mwait" cmdline param") The reasoning was that modern machines should be sufficiently happy during the boot process using the default_idle() HALT loop, until cpuidle loads and either acpi_idle or intel_idle invoke the newer MWAIT-with-hints idle loop. But two machines reported problems: 1. Certain Core2-era machines support MWAIT-C1 and HALT only. MWAIT-C1 is preferred for optimal power and performance. But if they support just C1, cpuidle never loads and so they use the boot-time default idle loop forever. 2. Some laptops will boot-hang if HALT is used, but will boot successfully if MWAIT is used. This appears to be a hidden assumption in BIOS SMI, that is presumably valid on the proprietary OS where the BIOS was validated. https://bugzilla.kernel.org/show_bug.cgi?id=60770 So here we effectively revert the patch above, restoring the mwait_idle() loop. However, we don't bother restoring the idle=mwait cmdline parameter, since it appears to add no value. Maintainer notes: For 3.9, simply revert 69fb3676df for 3.10, patch -F3 applies, fuzz needed due to __cpuinit use in context For 3.11, 3.12, 3.13, this patch applies cleanly Tested-by: Mike Galbraith <bitbucket@online.de> Signed-off-by: Len Brown <len.brown@intel.com> Acked-by: Mike Galbraith <bitbucket@online.de> Cc: <stable@vger.kernel.org> # 3.9+ Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ian Malone <ibmalone@gmail.com> Cc: Josh Boyer <jwboyer@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/345254a551eb5a6a866e048d7ab570fd2193aca4.1389763084.git.len.brown@intel.com [ Ported to recent kernels. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-06-19x86, cpufeature: Convert more "features" to bugsBorislav Petkov1-1/+1
X86_FEATURE_FXSAVE_LEAK, X86_FEATURE_11AP and X86_FEATURE_CLFLUSH_MONITOR are not really features but synthetic bits we use for applying different bug workarounds. Call them what they really are, and make sure they get the proper cross-CPU behavior (OR rather than AND). Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1403042783-23278-1-git-send-email-bp@alien8.de Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-01-13sched/preempt: Fix up missed PREEMPT_NEED_RESCHED foldingPeter Zijlstra1-1/+1
With various drivers wanting to inject idle time; we get people calling idle routines outside of the idle loop proper. Therefore we need to be extra careful about not missing TIF_NEED_RESCHED -> PREEMPT_NEED_RESCHED propagations. While looking at this, I also realized there's a small window in the existing idle loop where we can miss TIF_NEED_RESCHED; when it hits right after the tif_need_resched() test at the end of the loop but right before the need_resched() test at the start of the loop. So move preempt_fold_need_resched() out of the loop where we're guaranteed to have TIF_NEED_RESCHED set. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-x9jgh45oeayzajz2mjt0y7d6@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-12-19x86, idle: Use static_cpu_has() for CLFLUSH workaround, add barriersH. Peter Anvin1-1/+4
Use static_cpu_has() to conditionalize the CLFLUSH workaround, and add memory barriers around it since the documentation is explicit that CLFLUSH is only ordered with respect to MFENCE. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Len Brown <len.brown@intel.com> Link: http://lkml.kernel.org/r/CA%2B55aFzGxcML7j8CEvQPYzh0W81uVoAAVmGctMOUZ7CZ1yYd2A@mail.gmail.com
2013-12-19x86, acpi, idle: Restructure the mwait idle routinesPeter Zijlstra1-0/+40
People seem to delight in writing wrong and broken mwait idle routines; collapse the lot. This leaves mwait_play_dead() the sole remaining user of __mwait() and new __mwait() users are probably doing it wrong. Also remove __sti_mwait() as its unused. Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Jacob Jun Pan <jacob.jun.pan@linux.intel.com> Cc: Mike Galbraith <bitbucket@online.de> Cc: Len Brown <lenb@kernel.org> Cc: Rui Zhang <rui.zhang@intel.com> Acked-by: Rafael Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20131212141654.616820819@infradead.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-02-09intel_idle: remove assumption of one C-state per MWAIT flagLen Brown1-0/+2
Remove the assumption that cstate_tables are indexed by MWAIT flag values. Each entry identifies itself via its own flags value. This change is needed to support multiple states that share the same MWAIT flags. Note that this can have an effect on what state is described by 'N' on cmdline intel_idle.max_cstate=N on some systems. intel_idle.max_cstate=0 still disables the driver intel_idle.max_cstate=1 still results in just C1(E) However, "place holders" in the sparse C-state name-space (eg. Atom) have been removed. Signed-off-by: Len Brown <len.brown@intel.com>
2013-02-09intel_idle: remove use and definition of MWAIT_MAX_NUM_CSTATESLen Brown1-1/+0
Cosmetic only. Replace use of MWAIT_MAX_NUM_CSTATES with CPUIDLE_STATE_MAX. They are both 8, so this patch has no functional change. The reason to change is that intel_idle will soon be able to export more than the 8 "major" states supported by MWAIT. When we hit that limit, it is important to know where the limit comes from. Signed-off-by: Len Brown <len.brown@intel.com>
2010-09-18x86, mwait: Move mwait constants to a common header fileH. Peter Anvin1-0/+15
We have MWAIT constants spread across three different .c files, for no good reason. Move them all into a common header file. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Reviewed-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Len Brown <lenb@kernel.org> LKML-Reference: <tip-*@git.kernel.org>