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2020-02-23efi: Use EFI ResetSystem only when availableArd Biesheuvel1-2/+2
Do not attempt to call EFI ResetSystem if the runtime supported mask tells us it is no longer functional at OS runtime. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
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>
2017-08-26efi/reboot: Make function pointer orig_pm_power_off staticColin Ian King1-1/+1
The function pointer orig_pm_power_off is local to the source and does not need to be in global scope, so make it static. Cleans up sparse warning: symbol 'orig_pm_power_off' was not declared. Should it be static? Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20170825155019.6740-4-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-21efi/reboot: Fall back to original power-off method if EFI_RESET_SHUTDOWN returnsHans de Goede1-1/+11
Commit: 44be28e9dd98 ("x86/reboot: Add EFI reboot quirk for ACPI Hardware Reduced flag") sets pm_power_off to efi_power_off() when the acpi_gbl_reduced_hardware flag is set. According to its commit message this is necessary because: "BayTrail-T class of hardware requires EFI in order to powerdown and reboot and no other reliable method exists". But I have a Bay Trail CR tablet where the EFI_RESET_SHUTDOWN call does not work, it simply returns without doing anything (AFAICT). So it seems that some Bay Trail devices must use EFI for power-off, while for others only ACPI works. Note that efi_power_off() only gets used if the platform code defines efi_poweroff_required() and that returns true, this currently only ever happens on x86. Since on the devices which need ACPI for power-off the EFI_RESET_SHUTDOWN call simply returns, this patch makes the efi-reboot code remember the old pm_power_off handler and if EFI_RESET_SHUTDOWN returns it falls back to calling that. This seems preferable to dmi-quirking our way out of this, since there are likely quite a few devices suffering from this. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Len Brown <lenb@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mark Salter <msalter@redhat.com> Cc: Peter Jones <pjones@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rjw@rjwysocki.net> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20170818194947.19347-7-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi: Add 'capsule' update supportMatt Fleming1-1/+11
The EFI capsule mechanism allows data blobs to be passed to the EFI firmware. A common use case is performing firmware updates. This patch just introduces the main infrastructure for interacting with the firmware, and a driver that allows users to upload capsules will come in a later patch. Once a capsule has been passed to the firmware, the next reboot must be performed using the ResetSystem() EFI runtime service, which may involve overriding the reboot type specified by reboot=. This ensures the reset value returned by QueryCapsuleCapabilities() is used to reset the system, which is required for the capsule to be processed. efi_capsule_pending() is provided for this purpose. At the moment we only allow a single capsule blob to be sent to the firmware despite the fact that UpdateCapsule() takes a 'CapsuleCount' parameter. This simplifies the API and shouldn't result in any downside since it is still possible to send multiple capsules by repeatedly calling UpdateCapsule(). Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Bryan O'Donoghue <pure.logic@nexus-software.ie> Cc: Kweh Hock Leong <hock.leong.kweh@intel.com> Cc: Mark Salter <msalter@redhat.com> Cc: Peter Jones <pjones@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: joeyli <jlee@suse.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-28-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-07-19x86/reboot: Add EFI reboot quirk for ACPI Hardware Reduced flagMatt Fleming1-0/+8
It appears that the BayTrail-T class of hardware requires EFI in order to powerdown and reboot and no other reliable method exists. This quirk is generally applicable to all hardware that has the ACPI Hardware Reduced bit set, since usually ACPI would be the preferred method. Cc: Len Brown <len.brown@intel.com> Cc: Mark Salter <msalter@redhat.com> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-07-19efi/reboot: Allow powering off machines using EFIMatt Fleming1-0/+22
Not only can EfiResetSystem() be used to reboot, it can also be used to power down machines. By and large, this functionality doesn't work very well across the range of EFI machines in the wild, so it should definitely only be used as a last resort. In an ideal world, this wouldn't be needed at all. Unfortunately, we're starting to see machines where EFI is the *only* reliable way to power down, and nothing else, not PCI, not ACPI, works. efi_poweroff_required() should be implemented on a per-architecture basis, since exactly when we should be using EFI runtime services is a platform-specific decision. There's no analogue for reboot because each architecture handles reboot very differently - the x86 code in particular is pretty complex. Patches to enable this for specific classes of hardware will be submitted separately. Tested-by: Mark Salter <msalter@redhat.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-07-19efi/reboot: Add generic wrapper around EfiResetSystem()Matt Fleming1-0/+26
Implement efi_reboot(), which is really just a wrapper around the EfiResetSystem() EFI runtime service, but it does at least allow us to funnel all callers through a single location. It also simplifies the callsites since users no longer need to check to see whether EFI_RUNTIME_SERVICES are enabled. Cc: Tony Luck <tony.luck@intel.com> Tested-by: Mark Salter <msalter@redhat.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>