On Tue, Apr 06, 2021 at 08:35:55PM +0200, Paolo Bonzini wrote:
On 06/04/21 20:25, Greg KH wrote:
On Tue, Apr 06, 2021 at 12:25:50PM -0400, Paolo Bonzini wrote:
Right now, if a call to kvm_tdp_mmu_zap_sp returns false, the caller will skip the TLB flush, which is wrong. There are two ways to fix it:
since kvm_tdp_mmu_zap_sp will not yield and therefore will not flush the TLB itself, we could change the call to kvm_tdp_mmu_zap_sp to use "flush |= ..."
or we can chain the flush argument through kvm_tdp_mmu_zap_sp down to __kvm_tdp_mmu_zap_gfn_range.
This patch does the former to simplify application to stable kernels.
Cc: seanjc@google.com Fixes: 048f49809c526 ("KVM: x86/mmu: Ensure TLBs are flushed for TDP MMU during NX zapping") Cc: stable@vger.kernel.org # 5.10.x: 048f49809c: KVM: x86/mmu: Ensure TLBs are flushed for TDP MMU during NX zapping Cc: stable@vger.kernel.org # 5.10.x: 33a3164161: KVM: x86/mmu: Don't allow TDP MMU to yield when recovering NX pages Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini pbonzini@redhat.com
arch/x86/kvm/mmu/mmu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
Is this for only the stable kernels, or is it addressed toward upstream merges?
Confused,
It's for upstream. I'll include it (with the expected "[ Upstream commit abcd ]" header) when I post the complete backport. I'll send this patch to Linus as soon as I get a review even if I don't have anything else in the queue, so (as a general idea) the full backport should be sent and tested on Thursday-Friday.
Ah, ok, thanks, got confused there.
greg k-h