kernel.git/arch/x86/include/uapi/asm, branch linux-4.14.y

x86/kvm/lapic: always disable MMIO interface in x2APIC mode

2018-10-18T07:16:23Z

[ Upstream commit d1766202779e81d0f2a94c4650a6ba31497d369d ] When VMX is used with flexpriority disabled (because of no support or if disabled with module parameter) MMIO interface to lAPIC is still available in x2APIC mode while it shouldn't be (kvm-unit-tests): PASS: apic_disable: Local apic enabled in x2APIC mode PASS: apic_disable: CPUID.1H:EDX.APIC[bit 9] is set FAIL: apic_disable: *0xfee00030: 50014 The issue appears because we basically do nothing while switching to x2APIC mode when APIC access page is not used. apic_mmio_{read,write} only check if lAPIC is disabled before proceeding to actual write. When APIC access is virtualized we correctly manipulate with VMX controls in vmx_set_virtual_apic_mode() and we don't get vmexits from memory writes in x2APIC mode so there's no issue. Disabling MMIO interface seems to be easy. The question is: what do we do with these reads and writes? If we add apic_x2apic_mode() check to apic_mmio_in_range() and return -EOPNOTSUPP these reads and writes will go to userspace. When lAPIC is in kernel, Qemu uses this interface to inject MSIs only (see kvm_apic_mem_write() in hw/i386/kvm/apic.c). This somehow works with disabled lAPIC but when we're in xAPIC mode we will get a real injected MSI from every write to lAPIC. Not good. The simplest solution seems to be to just ignore writes to the region and return ~0 for all reads when we're in x2APIC mode. This is what this patch does. However, this approach is inconsistent with what currently happens when flexpriority is enabled: we allocate APIC access page and create KVM memory region so in x2APIC modes all reads and writes go to this pre-allocated page which is, btw, the same for all vCPUs. Signed-off-by: Vitaly Kuznetsov Signed-off-by: Paolo Bonzini Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

x86/ipc: Fix x32 version of shmid64_ds and msqid64_ds

2018-05-01T19:58:26Z

commit 1a512c0882bd311c5b5561840fcfbe4c25b8f319 upstream. A bugfix broke the x32 shmid64_ds and msqid64_ds data structure layout (as seen from user space) a few years ago: Originally, __BITS_PER_LONG was defined as 64 on x32, so we did not have padding after the 64-bit __kernel_time_t fields, After __BITS_PER_LONG got changed to 32, applications would observe extra padding. In other parts of the uapi headers we seem to have a mix of those expecting either 32 or 64 on x32 applications, so we can't easily revert the path that broke these two structures. Instead, this patch decouples x32 from the other architectures and moves it back into arch specific headers, partially reverting the even older commit 73a2d096fdf2 ("x86: remove all now-duplicate header files"). It's not clear whether this ever made any difference, since at least glibc carries its own (correct) copy of both of these header files, so possibly no application has ever observed the definitions here. Based on a suggestion from H.J. Lu, I tried out the tool from https://github.com/hjl-tools/linux-header to find other such bugs, which pointed out the same bug in statfs(), which also has a separate (correct) copy in glibc. Fixes: f4b4aae18288 ("x86/headers/uapi: Fix __BITS_PER_LONG value for x32 builds") Signed-off-by: Arnd Bergmann Signed-off-by: Thomas Gleixner Cc: "H . J . Lu" Cc: Jeffrey Walton Cc: stable@vger.kernel.org Cc: "H. Peter Anvin" Link: https://lkml.kernel.org/r/20180424212013.3967461-1-arnd@arndb.de Signed-off-by: Greg Kroah-Hartman

x86/MCE: Save microcode revision in machine check records

2018-03-15T09:54:33Z

commit fa94d0c6e0f3431523f5701084d799c77c7d4a4f upstream. Updating microcode used to be relatively rare. Now that it has become more common we should save the microcode version in a machine check record to make sure that those people looking at the error have this important information bundled with the rest of the logged information. [ Borislav: Simplify a bit. ] Signed-off-by: Tony Luck Signed-off-by: Borislav Petkov Signed-off-by: Thomas Gleixner Cc: Yazen Ghannam Cc: linux-edac Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20180301233449.24311-1-tony.luck@intel.com Signed-off-by: Greg Kroah-Hartman

KVM: x86: fix backward migration with async_PF

2018-03-11T15:23:23Z

commit fe2a3027e74e40a3ece3a4c1e4e51403090a907a upstream. Guests on new hypersiors might set KVM_ASYNC_PF_DELIVERY_AS_PF_VMEXIT bit when enabling async_PF, but this bit is reserved on old hypervisors, which results in a failure upon migration. To avoid breaking different cases, we are checking for CPUID feature bit before enabling the feature and nothing else. Fixes: 52a5c155cf79 ("KVM: async_pf: Let guest support delivery of async_pf from guest mode") Cc: Reviewed-by: Wanpeng Li Reviewed-by: David Hildenbrand Signed-off-by: Radim Krčmář Signed-off-by: Paolo Bonzini [jwang: port to 4.14] Signed-off-by: Jack Wang Signed-off-by: Greg Kroah-Hartman

x86/mm: Use/Fix PCID to optimize user/kernel switches

2018-01-02T19:31:01Z

commit 6fd166aae78c0ab738d49bda653cbd9e3b1491cf upstream. We can use PCID to retain the TLBs across CR3 switches; including those now part of the user/kernel switch. This increases performance of kernel entry/exit at the cost of more expensive/complicated TLB flushing. Now that we have two address spaces, one for kernel and one for user space, we need two PCIDs per mm. We use the top PCID bit to indicate a user PCID (just like we use the PFN LSB for the PGD). Since we do TLB invalidation from kernel space, the existing code will only invalidate the kernel PCID, we augment that by marking the corresponding user PCID invalid, and upon switching back to userspace, use a flushing CR3 write for the switch. In order to access the user_pcid_flush_mask we use PER_CPU storage, which means the previously established SWAPGS vs CR3 ordering is now mandatory and required. Having to do this memory access does require additional registers, most sites have a functioning stack and we can spill one (RAX), sites without functional stack need to otherwise provide the second scratch register. Note: PCID is generally available on Intel Sandybridge and later CPUs. Note: Up until this point TLB flushing was broken in this series. Based-on-code-from: Dave Hansen Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Thomas Gleixner Cc: Andy Lutomirski Cc: Boris Ostrovsky Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: David Laight Cc: Denys Vlasenko Cc: Eduardo Valentin Cc: Greg KH Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Juergen Gross Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Will Deacon Cc: aliguori@amazon.com Cc: daniel.gruss@iaik.tugraz.at Cc: hughd@google.com Cc: keescook@google.com Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

x86/boot: Relocate definition of the initial state of CR0

2017-12-25T13:26:16Z

commit b0ce5b8c95c83a7b98c679b117e3d6ae6f97154b upstream. Both head_32.S and head_64.S utilize the same value to initialize the control register CR0. Also, other parts of the kernel might want to access this initial definition (e.g., emulation code for User-Mode Instruction Prevention uses this state to provide a sane dummy value for CR0 when emulating the smsw instruction). Thus, relocate this definition to a header file from which it can be conveniently accessed. Suggested-by: Borislav Petkov Signed-off-by: Ricardo Neri Signed-off-by: Thomas Gleixner Reviewed-by: Borislav Petkov Reviewed-by: Andy Lutomirski Cc: "Michael S. Tsirkin" Cc: Peter Zijlstra Cc: Dave Hansen Cc: ricardo.neri@intel.com Cc: linux-mm@kvack.org Cc: Paul Gortmaker Cc: Huang Rui Cc: Shuah Khan Cc: linux-arch@vger.kernel.org Cc: Jonathan Corbet Cc: Jiri Slaby Cc: "Ravi V. Shankar" Cc: Denys Vlasenko Cc: Chris Metcalf Cc: Brian Gerst Cc: Josh Poimboeuf Cc: Chen Yucong Cc: Vlastimil Babka Cc: Dave Hansen Cc: Andy Lutomirski Cc: Masami Hiramatsu Cc: Paolo Bonzini Cc: Andrew Morton Cc: Linus Torvalds Link: https://lkml.kernel.org/r/1509135945-13762-3-git-send-email-ricardo.neri-calderon@linux.intel.com Signed-off-by: Greg Kroah-Hartman

License cleanup: add SPDX license identifier to uapi header files with a license

2017-11-02T10:20:11Z

Many user space API headers have licensing information, which is either incomplete, badly formatted or just a shorthand for referring to the license under which the file is supposed to be. This makes it hard for compliance tools to determine the correct license. Update these files with an SPDX license identifier. The identifier was chosen based on the license information in the file. GPL/LGPL licensed headers get the matching GPL/LGPL SPDX license identifier with the added 'WITH Linux-syscall-note' exception, which is the officially assigned exception identifier for the kernel syscall exception: NOTE! This copyright does *not* cover user programs that use kernel services by normal system calls - this is merely considered normal use of the kernel, and does *not* fall under the heading of "derived work". This exception makes it possible to include GPL headers into non GPL code, without confusing license compliance tools. Headers which have either explicit dual licensing or are just licensed under a non GPL license are updated with the corresponding SPDX identifier and the GPLv2 with syscall exception identifier. The format is: ((GPL-2.0 WITH Linux-syscall-note) OR SPDX-ID-OF-OTHER-LICENSE) SPDX license identifiers are a legally binding shorthand, which can be used instead of the full boiler plate text. The update does not remove existing license information as this has to be done on a case by case basis and the copyright holders might have to be consulted. This will happen in a separate step. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. See the previous patch in this series for the methodology of how this patch was researched. Reviewed-by: Kate Stewart Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

License cleanup: add SPDX license identifier to uapi header files with no license

2017-11-02T10:19:54Z

Many user space API headers are missing licensing information, which makes it hard for compliance tools to determine the correct license. By default are files without license information under the default license of the kernel, which is GPLV2. Marking them GPLV2 would exclude them from being included in non GPLV2 code, which is obviously not intended. The user space API headers fall under the syscall exception which is in the kernels COPYING file: NOTE! This copyright does *not* cover user programs that use kernel services by normal system calls - this is merely considered normal use of the kernel, and does *not* fall under the heading of "derived work". otherwise syscall usage would not be possible. Update the files which contain no license information with an SPDX license identifier. The chosen identifier is 'GPL-2.0 WITH Linux-syscall-note' which is the officially assigned identifier for the Linux syscall exception. SPDX license identifiers are 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. See the previous patch in this series for the methodology of how this patch was researched. Reviewed-by: Kate Stewart Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

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

x86/hyper-v: Remove duplicated HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED definition

2017-09-13T09:29:46Z

Commits: 7dcf90e9e032 ("PCI: hv: Use vPCI protocol version 1.2") 628f54cc6451 ("x86/hyper-v: Support extended CPU ranges for TLB flush hypercalls") added the same definition and they came in through different trees. Fix the duplication. Signed-off-by: Vitaly Kuznetsov Cc: Haiyang Zhang Cc: K. Y. Srinivasan Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Stephen Hemminger Cc: Thomas Gleixner Cc: devel@linuxdriverproject.org Link: http://lkml.kernel.org/r/20170911150620.3998-1-vkuznets@redhat.com Signed-off-by: Ingo Molnar