Comment 1 for bug 1834522

# BISECT LOG

git bisect start
# bad: [0adb32858b0bddf4ada5f364a84ed60b196dbcda] Linux 4.16
git bisect bad 0adb32858b0bddf4ada5f364a84ed60b196dbcda
# good: [d8a5b80568a9cb66810e75b182018e9edb68e8ff] Linux 4.15
git bisect good d8a5b80568a9cb66810e75b182018e9edb68e8ff
# good: [c14376de3a1befa70d9811ca2872d47367b48767] printk: Wake klogd when passing console_lock owner
git bisect good c14376de3a1befa70d9811ca2872d47367b48767
# good: [2246edfaf88dc368e8671b04afd54412625df60a] Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma
git bisect good 2246edfaf88dc368e8671b04afd54412625df60a
# good: [dfe8db22372873d205c78a9fd5370b1b088a2b87] Merge tag 'drm-misc-fixes-2018-02-21' of git://anongit.freedesktop.org/drm/drm-misc into drm-fixes
git bisect good dfe8db22372873d205c78a9fd5370b1b088a2b87
# bad: [4665c6b04651e96c1e2eb9129a30d6055040ff73] Merge tag 'linux-can-fixes-for-4.16-20180312' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can
git bisect bad 4665c6b04651e96c1e2eb9129a30d6055040ff73
# bad: [3499de32fa6b608ba646380ac3838d30a2558ead] Merge tag 'linux-kselftest-4.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
git bisect bad 3499de32fa6b608ba646380ac3838d30a2558ead
# good: [65738c6b461a8bb0b056e024299738f7cc9a28b7] Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
git bisect good 65738c6b461a8bb0b056e024299738f7cc9a28b7
# good: [c23a75759191e84f4ba15b85ea4f97bd544b5362] Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
git bisect good c23a75759191e84f4ba15b85ea4f97bd544b5362
# bad: [d4858aaf6bd8a90e2dacc0dfec2077e334dcedbf] Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
git bisect bad d4858aaf6bd8a90e2dacc0dfec2077e334dcedbf
# good: [0eb578009a1d530a11846d7c4733a5db04730884] tools/kvm_stat: use a more pythonic way to iterate over dictionaries
git bisect good 0eb578009a1d530a11846d7c4733a5db04730884
# good: [fe2a3027e74e40a3ece3a4c1e4e51403090a907a] KVM: x86: fix backward migration with async_PF
git bisect good fe2a3027e74e40a3ece3a4c1e4e51403090a907a
# bad: [7607b7174405aec7441ff6c970833c463114040a] KVM: SVM: install RSM intercept
git bisect bad 7607b7174405aec7441ff6c970833c463114040a
# good: [e5699f56bc91a286f006b0728085e0b4e8f5749b] crypto: ccp: Fix sparse, use plain integer as NULL pointer
git bisect good e5699f56bc91a286f006b0728085e0b4e8f5749b
# good: [3e233385ef4a217a2812115ed84d4be36eb16817] KVM: SVM: no need to call access_ok() in LAUNCH_MEASURE command
git bisect good 3e233385ef4a217a2812115ed84d4be36eb16817
# first bad commit: [7607b7174405aec7441ff6c970833c463114040a] KVM: SVM: install RSM intercept

# NOTE

I was doing "invert" bisection.. so the bad commit is actually what seems to have fixed the issue:

commit 7607b7174405aec7441ff6c970833c463114040a
Author: Brijesh Singh <email address hidden>
Date: Mon Feb 19 10:14:44 2018 -0600

    KVM: SVM: install RSM intercept

    RSM instruction is used by the SMM handler to return from SMM mode.
    Currently, rsm causes a #UD - which results in instruction fetch, decode,
    and emulate. By installing the RSM intercept we can avoid the instruction
    fetch since we know that #VMEXIT was due to rsm.

    The patch is required for the SEV guest, because in case of SEV guest
    memory is encrypted with guest-specific key and hypervisor will not
    able to fetch the instruction bytes from the guest memory.

    Cc: Paolo Bonzini <email address hidden>
    Cc: Radim Krčmář <email address hidden>
    Cc: Joerg Roedel <joro@8bytes.org>
    Cc: Borislav Petkov <email address hidden>
    Cc: Tom Lendacky <email address hidden>
    Signed-off-by: Brijesh Singh <email address hidden>
    Signed-off-by: Paolo Bonzini <email address hidden>