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Shutemov" Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable X-Stat-Signature: uish33qjka3qaowb6zhxm8cmrag3npa1 X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 904F340014 X-Rspam-User: X-HE-Tag: 1698936093-117835 X-HE-Meta: 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 cQI3qiKm 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Thu, Nov 02, 2023, Fuad Tabba wrote: > Hi, >=20 > On Fri, Oct 27, 2023 at 7:22=E2=80=AFPM Sean Christopherson wrote: > > > > Add flags to "struct kvm_gfn_range" to let notifier events target only > > shared and only private mappings, and write up the existing mmu_notifie= r > > events to be shared-only (private memory is never associated with a > > userspace virtual address, i.e. can't be reached via mmu_notifiers). > > > > Add two flags so that KVM can handle the three possibilities (shared, > > private, and shared+private) without needing something like a tri-state > > enum. > > > > Link: https://lore.kernel.org/all/ZJX0hk+KpQP0KUyB@google.com > > Signed-off-by: Sean Christopherson > > --- > > include/linux/kvm_host.h | 2 ++ > > virt/kvm/kvm_main.c | 7 +++++++ > > 2 files changed, 9 insertions(+) > > > > diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h > > index 96aa930536b1..89c1a991a3b8 100644 > > --- a/include/linux/kvm_host.h > > +++ b/include/linux/kvm_host.h > > @@ -263,6 +263,8 @@ struct kvm_gfn_range { > > gfn_t start; > > gfn_t end; > > union kvm_mmu_notifier_arg arg; > > + bool only_private; > > + bool only_shared; >=20 > If these flags aren't used in this patch series, should this patch be > moved to the other series? If *both* TDX and SNP need this patch, then I think it's probably worth app= lying it now to make their lives easier. But if only one needs the support, then= I completely agree this should be punted to whichever series needs it (this a= lso came up in v11, but we didn't force the issue). Mike, Isaku? > Also, if shared+private is a possibility, doesn't the prefix "only_" > confuse things a bit? I.e., what is shared+private, is it when both > are 0 or when both are 1? I assume it's the former (both are 0), but > it might be clearer. Heh, I was hoping that "only_private && only_shared" would be obviously non= sensical. The only alternative I can think would be to add an enum, e.g. enum { PROCESS_PRIVATE_AND_SHARED, PROCESS_ONLY_PRIVATE, PROCESS_ONLY_SHARED, }; because every other way of expressing the flags either results in more conf= usion or an unsafe default. I.e. I want zapping only private or only shared to r= equire the caller to explicitly set a non-zero value, which is how I ended up with "only_{private,shared}" as opposed to "process_{private,shared}".