On Mon, Aug 24, 2026 at 09:17:48AM -0400, Peter Xu wrote:
> On Sun, Aug 23, 2026 at 10:52:13AM -0500, Michael Roth wrote:
> > On Fri, Aug 21, 2026 at 10:18:26AM -0400, Peter Xu wrote:
> > > On Wed, Aug 12, 2026 at 03:16:38PM -0500, Michael Roth wrote:
> > > > v1: https://lore.kernel.org/r/20251023185913.2923322-1-peterx@redhat.com
> > > > v2: https://lore.kernel.org/r/20251119172913.577392-1-peterx@redhat.com
> > > > v3: https://lore.kernel.org/r/20251215205203.1185099-1-peterx@redhat.com/
> > > > v4:
> > > > - Picked up v3 series from Peter Xu and rebased on 11.1.0
> > > > - Collected pending Reviewed-by's
> > > > - Per-patch changes:
> > > > [01/12] Fix blank space (Xiaoyao)
> > > > Fix commit message typos
> > > > [02/12] Drop duplicated error-handling for capability checks
> > > > [05/12] Fix up commit message, disambigurate "in-place" terminology (Xiaoyao)
> > > > [07/12] Fix up commit message, disambigurate "in-place" terminology (Xiaoyao)
> > > > [08/12] Disallow 'seal' and 'hugetlb' options based on guest-memfd=on
> > > > Fix minor typo in comment
> > > > [11/12] Fix up typo in g_test_skip() reason
> > > > Pending: Move kvm_guest_memfd_init_shared_supported() to
> > > > migration-util.c (Fabiano)
> > > >
> > > > This patchset is also available at:
> > > >
> > > > https://github.com/amdese/qemu/commits/gmem-shared-mem-v4
> > > >
> > > > and is based on top of v11.1.0
> > >
> > > Should I just pick this up? I'll touch up the commit log that Phil
> > > requested. Objections welcomed before next week.
> >
> > Hi Peter,
>
> Hi, Michael,
>
> >
> > No objection here, although I'll be posting new version of the in-place
> > conversion support later this week (~Wed-ish) and was planning to an
> > updated version of this series roughly the same time so which ever way
> > is best for you.
> >
> > If you do post one though there's also the missing 'return false' and
> > dropping the seal=off enforcement that Daniel noticed before we started
> > talking about introspection fun.
>
> I didn't mean to repost this series, I meant to pick it up for a pull.
> Sorry if it was confusing..
Ahh ok :) No problem!
>
> I want to make sure balls are rolling. From our side, we weren't rush on
> this one to land, as we'll need to wait for 1G to settle anyway, but if we
> have others (like your in-place series upcoming) pending, I think we should
> just land it sooner.
Agreed, LGTM!
>
> You're right, we need to fix things, I noticed it right after I sent the
> email and then I found CI / unit test failing.. but I haven't got a chance
> to say.. If you repost please check migration-test with --full, otherwise
> the gmemfd test will be skipped.
Ok, I had seen migration-test passing but I didn't run it with full so
I'll look into what's going on there.
>
> I have two fixups queued locally, I'll attach it here, please use it
> whatever way you like, I'll wait for your repost. NOTE: I touched up the
> hugetlb failure message when I fixed it up myself, but since you'll repost
> you can decide; please just treat it as a comment then, I just think the
> new err message is less strong because we will support it.
Ok, I'll get these rolled in as well.
Thanks!
-Mike
>
> Thanks,
>
> ===8<===
>
>
> From 0a0dd0f808d4f668ac099945ab35a981e1a07bfb Mon Sep 17 00:00:00 2001
> From: Peter Xu <peterx@redhat.com>
> Date: Fri, 21 Aug 2026 12:16:15 -0400
> Subject: [PATCH 1/2] fixup! hostmem: Support fully shared guest memfd to back
> a VM
>
> Signed-off-by: Peter Xu <peterx@redhat.com>
> ---
> backends/hostmem-memfd.c | 10 ++++++----
> 1 file changed, 6 insertions(+), 4 deletions(-)
>
> diff --git a/backends/hostmem-memfd.c b/backends/hostmem-memfd.c
> index fbe65b00be..6576331441 100644
> --- a/backends/hostmem-memfd.c
> +++ b/backends/hostmem-memfd.c
> @@ -57,14 +57,16 @@ memfd_backend_memory_alloc(HostMemoryBackend *backend, Error **errp)
> }
>
> if (m->guest_memfd) {
> + /*
> + * NOTE: guest-memfd ignores seal=on/off because it always
> + * implicitly seals the FD by definition.
> + */
> if (!backend->share) {
> error_setg(errp, "guest-memfd=on must be used with share=on");
> return false;
> - } else if (m->seal) {
> - error_setg(errp, "guest-memfd=on must be used with seal=off");
> - return false;
> } else if (m->hugetlb) {
> - error_setg(errp, "guest-memfd=on must be used with hugetlb=off");
> + error_setg(errp, "guest-memfd=on doesn't support hugetlb=on yet");
> + return false;
> }
>
> fd = kvm_create_guest_memfd(backend->size,
> --
> 2.54.0
>
>
>
> From 66ac7b3f2268430106bfe8034ef8460215e9db91 Mon Sep 17 00:00:00 2001
> From: Peter Xu <peterx@redhat.com>
> Date: Fri, 21 Aug 2026 13:00:09 -0400
> Subject: [PATCH 2/2] fixup! tests/migration-test: Add a precopy test for
> guest-memfd
>
> Signed-off-by: Peter Xu <peterx@redhat.com>
> ---
> tests/qtest/migration/precopy-tests.c | 1 -
> 1 file changed, 1 deletion(-)
>
> diff --git a/tests/qtest/migration/precopy-tests.c b/tests/qtest/migration/precopy-tests.c
> index 8146f37d61..d57ffcac23 100644
> --- a/tests/qtest/migration/precopy-tests.c
> +++ b/tests/qtest/migration/precopy-tests.c
> @@ -184,7 +184,6 @@ static void test_precopy_tcp_plain(char *name, MigrateCommon *args)
>
> static void test_precopy_tcp_plain_gmemfd(char *name, MigrateCommon *args)
> {
> - args->uri = "tcp:127.0.0.1:0";
> args->start.mem_type = MEM_TYPE_GUEST_MEMFD;
>
> test_precopy_common(args);
> --
> 2.54.0
>
>
> --
> Peter Xu
>