kernel/arch/arm/kvm/trace.h, branch linux-4.15.y

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

ARM: KVM: Fix tracepoint generation after move to virt/kvm/arm/

2017-05-15T06:58:50Z

Moving most of the shared code to virt/kvm/arm had for consequence that KVM/ARM doesn't build anymore, because the code that used to define the tracepoints is now somewhere else. Fix this by defining CREATE_TRACE_POINTS in coproc.c, and clean-up trace.h as well. Fixes: 35d2d5d490e2 ("KVM: arm/arm64: Move shared files to virt/kvm/arm") Reported-by: Arnd Bergmann Signed-off-by: Marc Zyngier Signed-off-by: Christoffer Dall

KVM: arm/arm64: Move shared files to virt/kvm/arm

2017-05-04T11:57:26Z

For some time now we have been having a lot of shared functionality between the arm and arm64 KVM support in arch/arm, which not only required a horrible inter-arch reference from the Makefile in arch/arm64/kvm, but also created confusion for newcomers to the code base, as was recently seen on the mailing list. Further, it causes confusion for things like cscope, which needs special attention to index specific shared files for arm64 from the arm tree. Move the shared files into virt/kvm/arm and move the trace points along with it. When moving the tracepoints we have to modify the way the vgic creates definitions of the trace points, so we take the chance to include the VGIC tracepoints in its very own special vgic trace.h file. Signed-off-by: Christoffer Dall

arm/arm64: KVM: Improve kvm_exit tracepoint

2015-10-22T21:01:47Z

The ARM architecture only saves the exit class to the HSR (ESR_EL2 for arm64) on synchronous exceptions, not on asynchronous exceptions like an IRQ. However, we only report the exception class on kvm_exit, which is confusing because an IRQ looks like it exited at some PC with the same reason as the previous exit. Add a lookup table for the exception index and prepend the kvm_exit tracepoint text with the exception type to clarify this situation. Also resolve the exception class (EC) to a human-friendly text version so the trace output becomes immediately usable for debugging this code. Cc: Wei Huang Signed-off-by: Christoffer Dall

arm/arm64: KVM: Optimize handling of Access Flag faults

2015-03-12T21:34:49Z

Now that we have page aging in Stage-2, it becomes obvious that we're doing way too much work handling the fault. The page is not going anywhere (it is still mapped), the page tables are already allocated, and all we want is to flip a bit in the PMD or PTE. Also, we can avoid any form of TLB invalidation, since a page with the AF bit off is not allowed to be cached. An obvious solution is to have a separate handler for FSC_ACCESS, where we pride ourselves to only do the very minimum amount of work. Signed-off-by: Marc Zyngier Acked-by: Christoffer Dall Signed-off-by: Christoffer Dall

arm/arm64: KVM: Implement Stage-2 page aging

2015-03-12T21:34:43Z

Until now, KVM/arm didn't care much for page aging (who was swapping anyway?), and simply provided empty hooks to the core KVM code. With server-type systems now being available, things are quite different. This patch implements very simple support for page aging, by clearing the Access flag in the Stage-2 page tables. On access fault, the current fault handling will write the PTE or PMD again, putting the Access flag back on. It should be possible to implement a much faster handling for Access faults, but that's left for a later patch. With this in place, performance in VMs is degraded much more gracefully. Signed-off-by: Marc Zyngier Acked-by: Christoffer Dall Signed-off-by: Christoffer Dall

arm/arm64: KVM: Add exit reaons to kvm_exit event tracing

2015-02-23T21:28:48Z

This patch extends trace_kvm_exit() to include KVM exit reasons (i.e. EC of HSR). The tracing function then dumps both exit reason and PC of vCPU, shown as the following. Tracing tools can use this new exit_reason field to better understand the behavior of guest VMs. 886.301252: kvm_exit: HSR_EC: 0x0024, PC: 0xfffffe0000506b28 Signed-off-by: Wei Huang Signed-off-by: Christoffer Dall

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

2015-02-13T17:55:09Z

Pull KVM update from Paolo Bonzini: "Fairly small update, but there are some interesting new features. Common: Optional support for adding a small amount of polling on each HLT instruction executed in the guest (or equivalent for other architectures). This can improve latency up to 50% on some scenarios (e.g. O_DSYNC writes or TCP_RR netperf tests). This also has to be enabled manually for now, but the plan is to auto-tune this in the future. ARM/ARM64: The highlights are support for GICv3 emulation and dirty page tracking s390: Several optimizations and bugfixes. Also a first: a feature exposed by KVM (UUID and long guest name in /proc/sysinfo) before it is available in IBM's hypervisor! :) MIPS: Bugfixes. x86: Support for PML (page modification logging, a new feature in Broadwell Xeons that speeds up dirty page tracking), nested virtualization improvements (nested APICv---a nice optimization), usual round of emulation fixes. There is also a new option to reduce latency of the TSC deadline timer in the guest; this needs to be tuned manually. Some commits are common between this pull and Catalin's; I see you have already included his tree. Powerpc: Nothing yet. The KVM/PPC changes will come in through the PPC maintainers, because I haven't received them yet and I might end up being offline for some part of next week" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (130 commits) KVM: ia64: drop kvm.h from installed user headers KVM: x86: fix build with !CONFIG_SMP KVM: x86: emulate: correct page fault error code for NoWrite instructions KVM: Disable compat ioctl for s390 KVM: s390: add cpu model support KVM: s390: use facilities and cpu_id per KVM KVM: s390/CPACF: Choose crypto control block format s390/kernel: Update /proc/sysinfo file with Extended Name and UUID KVM: s390: reenable LPP facility KVM: s390: floating irqs: fix user triggerable endless loop kvm: add halt_poll_ns module parameter kvm: remove KVM_MMIO_SIZE KVM: MIPS: Don't leak FPU/DSP to guest KVM: MIPS: Disable HTW while in guest KVM: nVMX: Enable nested posted interrupt processing KVM: nVMX: Enable nested virtual interrupt delivery KVM: nVMX: Enable nested apic register virtualization KVM: nVMX: Make nested control MSRs per-cpu KVM: nVMX: Enable nested virtualize x2apic mode KVM: nVMX: Prepare for using hardware MSR bitmap ...

arm/arm64: KVM: Use set/way op trapping to track the state of the caches

2015-01-29T22:24:56Z

Trying to emulate the behaviour of set/way cache ops is fairly pointless, as there are too many ways we can end-up missing stuff. Also, there is some system caches out there that simply ignore set/way operations. So instead of trying to implement them, let's convert it to VA ops, and use them as a way to re-enable the trapping of VM ops. That way, we can detect the point when the MMU/caches are turned off, and do a full VM flush (which is what the guest was trying to do anyway). This allows a 32bit zImage to boot on the APM thingy, and will probably help bootloaders in general. Signed-off-by: Marc Zyngier Signed-off-by: Christoffer Dall

ARM: KVM: extend WFI tracepoint to differentiate between wfi and wfe

2015-01-15T12:12:27Z

Currently the trace printk talks about "wfi" only, though the trace point triggers both on wfi and wfe traps. Add a parameter to differentiate between the two. Signed-off-by: Andre Przywara Reviewed-by: Wei Huang Signed-off-by: Christoffer Dall