In order to guarantee compatibility on migration, QEMU should have
complete control over the features it announces to the guest via CPUID.

However, a number of Hyper-V-related features happen to depend on the
support in the underlying KVM, with no regard to QEMU configuration.

Make QEMU regain control over what Hyper-V features it announces to the
guest.

Note: the patches are also being proposed for stable-2.11, even though
one of them introduces a new cpu property.  This is done to minimize the
number of published QEMU releases where the behavior of the features is
unpredictable, with potentially fatal consequences for the guest.

Note #2: there are other problems in the surrounding code, like ugly
error reporting or inconsistent population of MSRs.  I think this can be
put off to post-2.12.

Roman Kagan (2):
  i386/hyperv: add hv-frequencies cpu property
  i386/hyperv: error out if features requested but unsupported

Cc: qemu-stable@nongnu.org

 target/i386/cpu.h |  1 +
 target/i386/cpu.c |  1 +
 target/i386/kvm.c | 37 +++++++++++++++++++++++++++++--------
 3 files changed, 31 insertions(+), 8 deletions(-)

-- 
2.14.3

Hi,

This series seems to have some coding style problems. See output below for
more information:

Type: series
Message-id: 20180323125808.4479-1-rkagan@virtuozzo.com
Subject: [Qemu-devel] [PATCH for-2.12 0/2] i386/hyperv: fully control Hyper-V features in CPUID

=== TEST SCRIPT BEGIN ===
#!/bin/bash

BASE=base
n=1
total=$(git log --oneline $BASE.. | wc -l)
failed=0

git config --local diff.renamelimit 0
git config --local diff.renames True
git config --local diff.algorithm histogram

commits="$(git log --format=%H --reverse $BASE..)"
for c in $commits; do
    echo "Checking PATCH $n/$total: $(git log -n 1 --format=%s $c)..."
    if ! git show $c --format=email | ./scripts/checkpatch.pl --mailback -; then
        failed=1
        echo
    fi
    n=$((n+1))
done

exit $failed
=== TEST SCRIPT END ===

Updating 3c8cf5a9c21ff8782164d1def7f44bd888713384
Switched to a new branch 'test'
2efbb18fe2 i386/hyperv: error out if features requested but unsupported
31e7467f4e i386/hyperv: add hv-frequencies cpu property

=== OUTPUT BEGIN ===
Checking PATCH 1/2: i386/hyperv: add hv-frequencies cpu property...
Checking PATCH 2/2: i386/hyperv: error out if features requested but unsupported...
ERROR: suspect code indent for conditional statements (4, 7)
#39: FILE: target/i386/kvm.c:670:
+    if (cpu->hyperv_reset) {
+       if (!has_msr_hv_reset) {

total: 1 errors, 0 warnings, 38 lines checked

Your patch has style problems, please review.  If any of these errors
are false positives report them to the maintainer, see
CHECKPATCH in MAINTAINERS.

=== OUTPUT END ===

Test command exited with code: 1


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