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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>
2016-12-08KVM: x86: Handle the kthread worker using the new APIPetr Mladek
Use the new API to create and destroy the "kvm-pit" kthread worker. The API hides some implementation details. In particular, kthread_create_worker() allocates and initializes struct kthread_worker. It runs the kthread the right way and stores task_struct into the worker structure. kthread_destroy_worker() flushes all pending works, stops the kthread and frees the structure. This patch does not change the existing behavior except for dynamically allocating struct kthread_worker and storing only the pointer of this structure. It is compile tested only because I did not find an easy way how to run the code. Well, it should be pretty safe given the nature of the change. Signed-off-by: Petr Mladek <pmladek@suse.com> Message-Id: <1476877847-11217-1-git-send-email-pmladek@suse.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-04KVM: i8254: turn kvm_kpit_state.reinject into atomic_tRadim Krčmář
Document possible races between readers and concurrent update to the ioctl. Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-04KVM: i8254: remove pit and kvm from kvm_kpit_stateRadim Krčmář
kvm isn't ever used and pit can be accessed with container_of. If you *really* need kvm, pit_state_to_pit(ps)->kvm. Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-04KVM: i8254: remove notifiers from PIT discard policyRadim Krčmář
Discard policy doesn't rely on information from notifiers, so we don't need to register notifiers unconditionally. We kept correct counts in case userspace switched between policies during runtime, but that can be avoided by reseting the state. Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-04KVM: i8254: remove unnecessary uses of PIT state lockRadim Krčmář
- kvm_create_pit had to lock only because it exposed kvm->arch.vpit very early, but initialization doesn't use kvm->arch.vpit since the last patch, so we can drop locking. - kvm_free_pit is only run after there are no users of KVM and therefore is the sole actor. - Locking in kvm_vm_ioctl_reinject doesn't do anything, because reinject is only protected at that place. - kvm_pit_reset isn't used anywhere and its locking can be dropped if we hide it. Removing useless locking allows to see what actually is being protected by PIT state lock (values accessible from the guest). Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-04KVM: i8254: pass struct kvm_pit instead of kvm in PITRadim Krčmář
This patch passes struct kvm_pit into internal PIT functions. Those functions used to get PIT through kvm->arch.vpit, even though most of them never used *kvm for other purposes. Another benefit is that we don't need to set kvm->arch.vpit during initialization. Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-04KVM: i8254: use atomic_t instead of pit.inject_lockRadim Krčmář
The lock was an overkill, the same can be done with atomics. A mb() was added in kvm_pit_ack_irq, to pair with implicit barrier between pit_timer_fn and pit_do_work. The mb() prevents a race that could happen if pending == 0 and irq_ack == 0: kvm_pit_ack_irq: | pit_timer_fn: p = atomic_read(&ps->pending); | | atomic_inc(&ps->pending); | queue_work(pit_do_work); | pit_do_work: | atomic_xchg(&ps->irq_ack, 0); | return; atomic_set(&ps->irq_ack, 1); | if (p == 0) return; | where the interrupt would not be delivered in this tick of pit_timer_fn. PIT would have eventually delivered the interrupt, but we sacrifice perofmance to make sure that interrupts are not needlessly delayed. sfence isn't enough: atomic_dec_if_positive does atomic_read first and x86 can reorder loads before stores. lfence isn't enough: store can pass lfence, turning it into a nop. A compiler barrier would be more than enough as CPU needs to stall for unbelievably long to use fences. This patch doesn't do anything in kvm_pit_reset_reinject, because any order of resets can race, but the result differs by at most one interrupt, which is ok, because it's the same result as if the reset happened at a slightly different time. (Original code didn't protect the reset path with a proper lock, so users have to be robust.) Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-03-26KVM: move iodev.h from virt/kvm/ to include/kvmAndre Przywara
iodev.h contains definitions for the kvm_io_bus framework. This is needed both by the generic KVM code in virt/kvm as well as by architecture specific code under arch/. Putting the header file in virt/kvm and using local includes in the architecture part seems at least dodgy to me, so let's move the file into include/kvm, so that a more natural "#include <kvm/iodev.h>" can be used by all of the code. This also solves a problem later when using struct kvm_io_device in arm_vgic.h. Fixing up the FSF address in the GPL header and a wrong include path on the way. Signed-off-by: Andre Przywara <andre.przywara@arm.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-08-01KVM: fold kvm_pit_timer into kvm_kpit_stateAvi Kivity
One structure nests inside the other, providing no value at all. Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-08-01KVM: Simplify kvm_pit_timerAvi Kivity
'timer_mode_mask' is unused 'tscdeadline' is unused 't_ops' only adds needless indirection 'vcpu' is unused Remove. Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-08-01KVM: Remove internal timer abstractionAvi Kivity
kvm_timer_fn(), the sole inhabitant of timer.c, is only used by lapic.c. Move it there to make it easier to hack on it. struct kvm_timer is a thin wrapper around hrtimer, and only adds obfuscation. Move near its two users (with different names) to prepare for simplification. Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-04-27KVM: x86: Run PIT work in own kthreadJan Kiszka
We can't run PIT IRQ injection work in the interrupt context of the host timer. This would allow the user to influence the handler complexity by asking for a broadcast to a large number of VCPUs. Therefore, this work was pushed into workqueue context in 9d244caf2e. However, this prevents prioritizing the PIT injection over other task as workqueues share kernel threads. This replaces the workqueue with a kthread worker and gives that thread a name in the format "kvm-pit/<owner-process-pid>". That allows to identify and adjust the kthread priority according to the VM process parameters. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-05-11KVM: remove useless function declaration kvm_inject_pit_timer_irqs()Duan Jiong
Just remove useless function define kvm_inject_pit_timer_irqs() from file arch/x86/kvm/i8254.h Signed-off-by:Duan Jiong<djduanjiong@gmail.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11KVM: Remove base_addresss in kvm_pit since it is unusedJustin P. Mattock
The patch below removes unsigned long base_addresss; in i8254.h since it is unused. Signed-off-by: Justin P. Mattock <justinmattock@gmail.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01KVM: x86: Introduce a workqueue to deliver PIT timer interruptsChris Lalancette
We really want to "kvm_set_irq" during the hrtimer callback, but that is risky because that is during interrupt context. Instead, offload the work to a workqueue, which is a bit safer and should provide most of the same functionality. Signed-off-by: Chris Lalancette <clalance@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01KVM: Convert i8254/i8259 locks to raw_spinlocksThomas Gleixner
The i8254/i8259 locks need to be real spinlocks on preempt-rt. Convert them to raw_spinlock. No change for !RT kernels. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10KVM: PIT support for HPET legacy modeBeth Kon
When kvm is in hpet_legacy_mode, the hpet is providing the timer interrupt and the pit should not be. So in legacy mode, the pit timer is destroyed, but the *state* of the pit is maintained. So if kvm or the guest tries to modify the state of the pit, this modification is accepted, *except* that the timer isn't actually started. When we exit hpet_legacy_mode, the current state of the pit (which is up to date since we've been accepting modifications) is used to restart the pit timer. The saved_mode code in kvm_pit_load_count temporarily changes mode to 0xff in order to destroy the timer, but then restores the actual value, again maintaining "current" state of the pit for possible later reenablement. [avi: add some reserved storage in the ioctl; make SET_PIT2 IOW] [marcelo: fix memory corruption due to reserved storage] Signed-off-by: Beth Kon <eak@us.ibm.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10KVM: Allow PIT emulation without speaker portJan Kiszka
The in-kernel speaker emulation is only a dummy and also unneeded from the performance point of view. Rather, it takes user space support to generate sound output on the host, e.g. console beeps. To allow this, introduce KVM_CREATE_PIT2 which controls in-kernel speaker port emulation via a flag passed along the new IOCTL. It also leaves room for future extensions of the PIT configuration interface. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10KVM: unify part of generic timer handlingMarcelo Tosatti
Hide the internals of vcpu awakening / injection from the in-kernel emulated timers. This makes future changes in this logic easier and decreases the distance to more generic timer handling. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10KVM: PIT: remove unused scheduled variableMarcelo Tosatti
Unused. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24KVM: Reset PIT irq injection logic when the PIT IRQ is unmaskedAvi Kivity
While the PIT is masked the guest cannot ack the irq, so the reinject logic will never allow the interrupt to be injected. Fix by resetting the reinjection counters on unmask. Unbreaks Xen. Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24KVM: PIT: provide an option to disable interrupt reinjectionMarcelo Tosatti
Certain clocks (such as TSC) in older 2.6 guests overaccount for lost ticks, causing severe time drift. Interrupt reinjection magnifies the problem. Provide an option to disable it. [avi: allow room for expansion in case we want to disable reinjection of other timers] Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2008-10-28KVM: Fix guest shared interrupt with in-kernel irqchipSheng Yang
Every call of kvm_set_irq() should offer an irq_source_id, which is allocated by kvm_request_irq_source_id(). Based on irq_source_id, we identify the irq source and implement logical OR for shared level interrupts. The allocated irq_source_id can be freed by kvm_free_irq_source_id(). Currently, we support at most sizeof(unsigned long) different irq sources. [Amit: - rebase to kvm.git HEAD - move definition of KVM_USERSPACE_IRQ_SOURCE_ID to common file - move kvm_request_irq_source_id to the update_irq ioctl] [Xiantao: - Add kvm/ia64 stuff and make it work for kvm/ia64 guests] Signed-off-by: Sheng Yang <sheng@linux.intel.com> Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2008-10-15KVM: PIT: fix injection logic and countMarcelo Tosatti
The PIT injection logic is problematic under the following cases: 1) If there is a higher priority vector to be delivered by the time kvm_pit_timer_intr_post is invoked ps->inject_pending won't be set. This opens the possibility for missing many PIT event injections (say if guest executes hlt at this point). 2) ps->inject_pending is racy with more than two vcpus. Since there's no locking around read/dec of pt->pending, two vcpu's can inject two interrupts for a single pt->pending count. Fix 1 by using an irq ack notifier: only reinject when the previous irq has been acked. Fix 2 with appropriate locking around manipulation of pending count and irq_ack by the injection / ack paths. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27KVM: Add reset support for in kernel PITSheng Yang
Separate the reset part and prepare for reset support. Signed-off-by: Sheng Yang <sheng.yang@intel.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27KVM: Add save/restore supporting of in kernel PITSheng Yang
Signed-off-by: Sheng Yang <sheng.yang@intel.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27KVM: In kernel PIT modelSheng Yang
The patch moves the PIT model from userspace to kernel, and increases the timer accuracy greatly. [marcelo: make last_injected_time per-guest] Signed-off-by: Sheng Yang <sheng.yang@intel.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Tested-and-Acked-by: Alex Davis <alex14641@yahoo.com> Signed-off-by: Avi Kivity <avi@qumranet.com>