1. 16 Mar, 2020 1 commit
    • Paolo Bonzini's avatar
      KVM: x86: unify callbacks to load paging root · 689f3bf2
      Paolo Bonzini authored
      
      
      Similar to what kvm-intel.ko is doing, provide a single callback that
      merges svm_set_cr3, set_tdp_cr3 and nested_svm_set_tdp_cr3.
      
      This lets us unify the set_cr3 and set_tdp_cr3 entries in kvm_x86_ops.
      I'm doing that in this same patch because splitting it adds quite a bit
      of churn due to the need for forward declarations.  For the same reason
      the assignment to vcpu->arch.mmu->set_cr3 is moved to kvm_init_shadow_mmu
      from init_kvm_softmmu and nested_svm_init_mmu_context.
      
      Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
      689f3bf2
  2. 12 Feb, 2020 1 commit
  3. 04 Nov, 2019 1 commit
  4. 22 Aug, 2019 1 commit
    • Sean Christopherson's avatar
      KVM: x86/mmu: Add explicit access mask for MMIO SPTEs · 4af77151
      Sean Christopherson authored
      When shadow paging is enabled, KVM tracks the allowed access type for
      MMIO SPTEs so that it can do a permission check on a MMIO GVA cache hit
      without having to walk the guest's page tables.  The tracking is done
      by retaining the WRITE and USER bits of the access when inserting the
      MMIO SPTE (read access is implicitly allowed), which allows the MMIO
      page fault handler to retrieve and cache the WRITE/USER bits from the
      SPTE.
      
      Unfortunately for EPT, the mask used to retain the WRITE/USER bits is
      hardcoded using the x86 paging versions of the bits.  This funkiness
      happens to work because KVM uses a completely different mask/value for
      MMIO SPTEs when EPT is enabled, and the EPT mask/value just happens to
      overlap exactly with the x86 WRITE/USER bits[*].
      
      Explicitly define the access mask for MMIO SPTEs to accurately reflect
      that EPT does not want to incorporate any access bits into the SPTE, and
      so that KVM isn't subtly relying on EPT's WX bits always being set in
      MMIO SPTEs, e.g. attempting to use other bits for experimentation breaks
      horribly.
      
      Note, vcpu_match_mmio_gva() explicits prevents matching GVA==0, and all
      TDP flows explicit set mmio_gva to 0, i.e. zeroing vcpu->arch.access for
      EPT has no (known) functional impact.
      
      [*] Using WX to generate EPT misconfigurations (equivalent to reserved
          bit page fault) ensures KVM can employ its MMIO page fault tricks
          even platforms without reserved address bits.
      
      Fixes: ce88decf
      
       ("KVM: MMU: mmio page fault support")
      Signed-off-by: default avatarSean Christopherson <sean.j.christopherson@intel.com>
      Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
      4af77151
  5. 16 Apr, 2019 1 commit
    • Ben Gardon's avatar
      kvm: mmu: Fix overflow on kvm mmu page limit calculation · bc8a3d89
      Ben Gardon authored
      
      
      KVM bases its memory usage limits on the total number of guest pages
      across all memslots. However, those limits, and the calculations to
      produce them, use 32 bit unsigned integers. This can result in overflow
      if a VM has more guest pages that can be represented by a u32. As a
      result of this overflow, KVM can use a low limit on the number of MMU
      pages it will allocate. This makes KVM unable to map all of guest memory
      at once, prompting spurious faults.
      
      Tested: Ran all kvm-unit-tests on an Intel Haswell machine. This patch
      	introduced no new failures.
      
      Signed-off-by: default avatarBen Gardon <bgardon@google.com>
      Cc: stable@vger.kernel.org
      Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
      bc8a3d89
  6. 20 Feb, 2019 1 commit
  7. 16 Oct, 2018 2 commits
  8. 06 Aug, 2018 5 commits
  9. 02 Nov, 2017 1 commit
    • Greg Kroah-Hartman's avatar
      License cleanup: add SPDX GPL-2.0 license identifier to files with no license · b2441318
      Greg Kroah-Hartman authored
      
      
      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: default avatarKate Stewart <kstewart@linuxfoundation.org>
      Reviewed-by: default avatarPhilippe Ombredanne <pombredanne@nexb.com>
      Reviewed-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      b2441318
  10. 12 Oct, 2017 1 commit
  11. 26 Aug, 2017 1 commit
  12. 25 Aug, 2017 1 commit
  13. 24 Aug, 2017 3 commits
  14. 18 Aug, 2017 1 commit
  15. 18 Jul, 2017 1 commit
    • Tom Lendacky's avatar
      kvm/x86/svm: Support Secure Memory Encryption within KVM · d0ec49d4
      Tom Lendacky authored
      
      
      Update the KVM support to work with SME. The VMCB has a number of fields
      where physical addresses are used and these addresses must contain the
      memory encryption mask in order to properly access the encrypted memory.
      Also, use the memory encryption mask when creating and using the nested
      page tables.
      
      Signed-off-by: default avatarTom Lendacky <thomas.lendacky@amd.com>
      Reviewed-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Reviewed-by: default avatarBorislav Petkov <bp@suse.de>
      Cc: Alexander Potapenko <glider@google.com>
      Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brijesh Singh <brijesh.singh@amd.com>
      Cc: Dave Young <dyoung@redhat.com>
      Cc: Dmitry Vyukov <dvyukov@google.com>
      Cc: Jonathan Corbet <corbet@lwn.net>
      Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      Cc: Larry Woodman <lwoodman@redhat.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Matt Fleming <matt@codeblueprint.co.uk>
      Cc: Michael S. Tsirkin <mst@redhat.com>
      Cc: Paolo Bonzini <pbonzini@redhat.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Radim Krčmář <rkrcmar@redhat.com>
      Cc: Rik van Riel <riel@redhat.com>
      Cc: Toshimitsu Kani <toshi.kani@hpe.com>
      Cc: kasan-dev@googlegroups.com
      Cc: kvm@vger.kernel.org
      Cc: linux-arch@vger.kernel.org
      Cc: linux-doc@vger.kernel.org
      Cc: linux-efi@vger.kernel.org
      Cc: linux-mm@kvack.org
      Link: http://lkml.kernel.org/r/89146eccfa50334409801ff20acd52a90fb5efcf.1500319216.git.thomas.lendacky@amd.com
      
      
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      d0ec49d4
  16. 14 Jul, 2017 1 commit
  17. 03 Jul, 2017 1 commit
  18. 11 Jun, 2017 1 commit
    • Wanpeng Li's avatar
      KVM: async_pf: avoid async pf injection when in guest mode · 9bc1f09f
      Wanpeng Li authored
      
      
       INFO: task gnome-terminal-:1734 blocked for more than 120 seconds.
             Not tainted 4.12.0-rc4+ #8
       "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
       gnome-terminal- D    0  1734   1015 0x00000000
       Call Trace:
        __schedule+0x3cd/0xb30
        schedule+0x40/0x90
        kvm_async_pf_task_wait+0x1cc/0x270
        ? __vfs_read+0x37/0x150
        ? prepare_to_swait+0x22/0x70
        do_async_page_fault+0x77/0xb0
        ? do_async_page_fault+0x77/0xb0
        async_page_fault+0x28/0x30
      
      This is triggered by running both win7 and win2016 on L1 KVM simultaneously,
      and then gives stress to memory on L1, I can observed this hang on L1 when
      at least ~70% swap area is occupied on L0.
      
      This is due to async pf was injected to L2 which should be injected to L1,
      L2 guest starts receiving pagefault w/ bogus %cr2(apf token from the host
      actually), and L1 guest starts accumulating tasks stuck in D state in
      kvm_async_pf_task_wait() since missing PAGE_READY async_pfs.
      
      This patch fixes the hang by doing async pf when executing L1 guest.
      
      Cc: Paolo Bonzini <pbonzini@redhat.com>
      Cc: Radim Krčmář <rkrcmar@redhat.com>
      Cc: stable@vger.kernel.org
      Signed-off-by: default avatarWanpeng Li <wanpeng.li@hotmail.com>
      Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
      9bc1f09f
  19. 09 May, 2017 1 commit
  20. 07 Apr, 2017 1 commit
    • Paolo Bonzini's avatar
      kvm: nVMX: support EPT accessed/dirty bits · ae1e2d10
      Paolo Bonzini authored
      
      
      Now use bit 6 of EPTP to optionally enable A/D bits for EPTP.  Another
      thing to change is that, when EPT accessed and dirty bits are not in use,
      VMX treats accesses to guest paging structures as data reads.  When they
      are in use (bit 6 of EPTP is set), they are treated as writes and the
      corresponding EPT dirty bit is set.  The MMU didn't know this detail,
      so this patch adds it.
      
      We also have to fix up the exit qualification.  It may be wrong because
      KVM sets bit 6 but the guest might not.
      
      L1 emulates EPT A/D bits using write permissions, so in principle it may
      be possible for EPT A/D bits to be used by L1 even though not available
      in hardware.  The problem is that guest page-table walks will be treated
      as reads rather than writes, so they would not cause an EPT violation.
      
      Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
      [Fixed typo in walk_addr_generic() comment and changed bit clear +
       conditional-set pattern in handle_ept_violation() to conditional-clear]
      Signed-off-by: default avatarRadim Krčmář <rkrcmar@redhat.com>
      ae1e2d10
  21. 14 Jul, 2016 1 commit
  22. 10 Apr, 2016 1 commit
    • Xiao Guangrong's avatar
      KVM: MMU: fix permission_fault() · 7a98205d
      Xiao Guangrong authored
      
      
      kvm-unit-tests complained about the PFEC is not set properly, e.g,:
      test pte.rw pte.d pte.nx pde.p pde.rw pde.pse user fetch: FAIL: error code 15
      expected 5
      Dump mapping: address: 0x123400000000
      ------L4: 3e95007
      ------L3: 3e96007
      ------L2: 2000083
      
      It's caused by the reason that PFEC returned to guest is copied from the
      PFEC triggered by shadow page table
      
      This patch fixes it and makes the logic of updating errcode more clean
      
      Signed-off-by: default avatarXiao Guangrong <guangrong.xiao@linux.intel.com>
      [Do not assume pfec.p=1. - Paolo]
      Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
      7a98205d
  23. 22 Mar, 2016 2 commits
  24. 03 Mar, 2016 2 commits
  25. 10 Nov, 2015 1 commit
  26. 05 Aug, 2015 2 commits
  27. 19 May, 2015 3 commits
  28. 11 May, 2015 1 commit