From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paolo Bonzini Date: Sat, 08 Nov 2014 07:28:50 +0000 Subject: Re: [PATCH v13 6/7] arm: KVM: dirty log read write protect support Message-Id: <545DC632.6020002@redhat.com> List-Id: References: <1415320848-13813-7-git-send-email-m.smarduch@samsung.com> In-Reply-To: <1415320848-13813-7-git-send-email-m.smarduch@samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: kvm-ia64@vger.kernel.org On 07/11/2014 20:47, Mario Smarduch wrote: >> That can happen if the error occurred in the final >> copy to userspace, after page tables have been modified. > > Upon error return userspace should terminate logging, error out whether > used for migration or other use cases, with some stale spte TLBs cached > read/write, which doesn't appear to be harmful. Fair enough; for x86 I elected to always do the TLB flush, but you can do it differently. Perhaps add a comment with the above paragraph, thouhg. > But you mention 'final copy' which makes me think I'm missing something? I meant final copy before leaving the function. Paolo