[Qemu-commits] [qemu/qemu] b2ae52: target/i386: define md-clear bit

[Peter Maydell]

  Branch: refs/heads/master
  Home:   https://github.com/qemu/qemu
  Commit: b2ae52101fca7f9547ac2f388085dbc58f8fe1c0
      
https://github.com/qemu/qemu/commit/b2ae52101fca7f9547ac2f388085dbc58f8fe1c0
  Author: Paolo Bonzini <address@hidden>
  Date:   2019-05-21 (Tue, 21 May 2019)

  Changed paths:
    M target/i386/cpu.c

  Log Message:
  -----------
  target/i386: define md-clear bit

md-clear is a new CPUID bit which is set when microcode provides the
mechanism to invoke a flush of various exploitable CPU buffers by invoking
the VERW instruction.

Signed-off-by: Paolo Bonzini <address@hidden>
Message-Id: <address@hidden>
Signed-off-by: Eduardo Habkost <address@hidden>


  Commit: 2c7e82a30774730100da9dbe68d2360459030d91
      
https://github.com/qemu/qemu/commit/2c7e82a30774730100da9dbe68d2360459030d91
  Author: Daniel P. Berrangé <address@hidden>
  Date:   2019-05-21 (Tue, 21 May 2019)

  Changed paths:
    M docs/qemu-cpu-models.texi

  Log Message:
  -----------
  docs: recommend use of md-clear feature on all Intel CPUs

Update x86 CPU model guidance to recommend that the md-clear feature is
manually enabled with all Intel CPU models, when supported by the host
microcode.

Signed-off-by: Daniel P. Berrangé <address@hidden>
Message-Id: <address@hidden>
Signed-off-by: Eduardo Habkost <address@hidden>


  Commit: 20140a82c67467f53814ca197403d5e1b561a5e5
      
https://github.com/qemu/qemu/commit/20140a82c67467f53814ca197403d5e1b561a5e5
  Author: Paolo Bonzini <address@hidden>
  Date:   2019-05-21 (Tue, 21 May 2019)

  Changed paths:
    M target/i386/cpu.c

  Log Message:
  -----------
  target/i386: add MDS-NO feature

Microarchitectural Data Sampling is a hardware vulnerability which allows
unprivileged speculative access to data which is available in various CPU
internal buffers.

Some Intel processors use the ARCH_CAP_MDS_NO bit in the
IA32_ARCH_CAPABILITIES
MSR to report that they are not vulnerable, make it available to guests.

Signed-off-by: Paolo Bonzini <address@hidden>
Message-Id: <address@hidden>
Signed-off-by: Eduardo Habkost <address@hidden>


  Commit: 542ad0eb9571577107c125079fa11eaa368363f4
      
https://github.com/qemu/qemu/commit/542ad0eb9571577107c125079fa11eaa368363f4
  Author: Peter Maydell <address@hidden>
  Date:   2019-05-21 (Tue, 21 May 2019)

  Changed paths:
    M docs/qemu-cpu-models.texi
    M target/i386/cpu.c

  Log Message:
  -----------
  Merge remote-tracking branch 'remotes/ehabkost/tags/x86-next-pull-request' 
into staging

x86 MDS feature flags

md-clear and mds-no feature flags, for detection and mitigation
of MDS vulnerabilities (CVE-2018-12126, CVE-2018-12127,
CVE-2018-12130, CVE-2019-11091).

# gpg: Signature made Tue 21 May 2019 19:42:43 BST
# gpg:                using RSA key 2807936F984DC5A6
# gpg: Good signature from "Eduardo Habkost <address@hidden>" [full]
# Primary key fingerprint: 5A32 2FD5 ABC4 D3DB ACCF  D1AA 2807 936F 984D C5A6

* remotes/ehabkost/tags/x86-next-pull-request:
  target/i386: add MDS-NO feature
  docs: recommend use of md-clear feature on all Intel CPUs
  target/i386: define md-clear bit

Signed-off-by: Peter Maydell <address@hidden>


Compare: https://github.com/qemu/qemu/compare/a4f667b67149...542ad0eb9571