All of lore.kernel.org
 help / color / mirror / Atom feed
From: Sean Christopherson <seanjc@google.com>
To: Paolo Bonzini <pbonzini@redhat.com>
Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
	Vitaly Kuznetsov <vkuznets@redhat.com>,
	Sean Christopherson <sean.j.christopherson@intel.com>
Subject: Re: [FYI PATCH] Revert "KVM: x86/mmu: Zap only TDP MMU leafs in kvm_zap_gfn_range()"
Date: Fri, 25 Mar 2022 20:22:37 +0000	[thread overview]
Message-ID: <Yj4kjRSuBDfupRqW@google.com> (raw)
In-Reply-To: <78e3f054-829e-b00d-6c65-9ae622f301df@redhat.com>

On Fri, Mar 25, 2022, Paolo Bonzini wrote:
> On 3/25/22 00:57, Sean Christopherson wrote:
> > Can I have 1-2 weeks to try and root cause and fix the underlying issue before
> > sending reverts to Linus?  I really don't want to paper over a TLB flushing bug
> > or an off-by-one bug, and I really, really don't want to end up with another
> > scenario where KVM zaps everything just because.
> 
> Well, too late...  I didn't want to send a pull request that was broken,

Ah, I didn't see that it was in the initial pull request, thought it was only in
kvm/next.  I'll send a full patch.

> Mingwei provided a convincing reason for the breakage.

No, the side effects are completely benign, and arguably desirable.  The issue is
that KVM loses a pending TLB flush if there are multiple roots.

  reply	other threads:[~2022-03-25 20:22 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-03-18 16:48 [FYI PATCH] Revert "KVM: x86/mmu: Zap only TDP MMU leafs in kvm_zap_gfn_range()" Paolo Bonzini
2022-03-21  9:13 ` Paolo Bonzini
2022-03-24 23:57   ` Sean Christopherson
2022-03-25 10:38     ` Vitaly Kuznetsov
2022-03-25 11:21     ` Paolo Bonzini
2022-03-25 20:22       ` Sean Christopherson [this message]
2022-03-25 15:03     ` Vitaly Kuznetsov
2022-03-25 20:18       ` Sean Christopherson

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=Yj4kjRSuBDfupRqW@google.com \
    --to=seanjc@google.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=pbonzini@redhat.com \
    --cc=sean.j.christopherson@intel.com \
    --cc=vkuznets@redhat.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.