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author | Lai Jiangshan <laijs@linux.alibaba.com> | 2020-12-17 23:41:18 +0800 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-02-23 15:01:00 +0100 |
commit | fc1e3f5d1d7f77be91f85d7d4ce94ebfe3d8d284 (patch) | |
tree | 866ffdf47bec9a8467469b10199c55fb44004430 /Makefile | |
parent | 2c68bb33dad9f3cab171bb64e1766bc5a7e9b7e8 (diff) |
kvm: check tlbs_dirty directly
commit 88bf56d04bc3564542049ec4ec168a8b60d0b48c upstream
In kvm_mmu_notifier_invalidate_range_start(), tlbs_dirty is used as:
need_tlb_flush |= kvm->tlbs_dirty;
with need_tlb_flush's type being int and tlbs_dirty's type being long.
It means that tlbs_dirty is always used as int and the higher 32 bits
is useless. We need to check tlbs_dirty in a correct way and this
change checks it directly without propagating it to need_tlb_flush.
Note: it's _extremely_ unlikely this neglecting of higher 32 bits can
cause problems in practice. It would require encountering tlbs_dirty
on a 4 billion count boundary, and KVM would need to be using shadow
paging or be running a nested guest.
Cc: stable@vger.kernel.org
Fixes: a4ee1ca4a36e ("KVM: MMU: delay flush all tlbs on sync_page path")
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Message-Id: <20201217154118.16497-1-jiangshanlai@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[sudip: adjust context]
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'Makefile')
0 files changed, 0 insertions, 0 deletions