From: David Hildenbrand <david@redhat.com>
To: qemu-devel@nongnu.org
Cc: kvm@vger.kernel.org, qemu-s390x@nongnu.org,
Richard Henderson <rth@twiddle.net>,
Paolo Bonzini <pbonzini@redhat.com>,
"Dr . David Alan Gilbert" <dgilbert@redhat.com>,
Eduardo Habkost <ehabkost@redhat.com>,
"Michael S . Tsirkin" <mst@redhat.com>,
David Hildenbrand <david@redhat.com>,
Cornelia Huck <cohuck@redhat.com>,
Halil Pasic <pasic@linux.ibm.com>,
Christian Borntraeger <borntraeger@de.ibm.com>,
Janosch Frank <frankja@linux.ibm.com>
Subject: [PATCH v2 04/19] s390x/pv: Convert to ram_block_discard_disable()
Date: Wed, 20 May 2020 14:31:37 +0200 [thread overview]
Message-ID: <20200520123152.60527-5-david@redhat.com> (raw)
In-Reply-To: <20200520123152.60527-1-david@redhat.com>
Discarding RAM does not work as expected with protected VMs. Let's
switch to ram_block_discard_disable() for now, as we want to get rid
of qemu_balloon_inhibit(). Note that it will currently never fail, but
might fail in the future with new technologies (e.g., virtio-mem).
Cc: Richard Henderson <rth@twiddle.net>
Cc: Cornelia Huck <cohuck@redhat.com>
Cc: Halil Pasic <pasic@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
---
hw/s390x/s390-virtio-ccw.c | 22 +++++++++++++---------
1 file changed, 13 insertions(+), 9 deletions(-)
diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
index 67ae2e02ff..e82129e874 100644
--- a/hw/s390x/s390-virtio-ccw.c
+++ b/hw/s390x/s390-virtio-ccw.c
@@ -43,7 +43,6 @@
#include "hw/qdev-properties.h"
#include "hw/s390x/tod.h"
#include "sysemu/sysemu.h"
-#include "sysemu/balloon.h"
#include "hw/s390x/pv.h"
#include "migration/blocker.h"
@@ -329,7 +328,7 @@ static void s390_machine_unprotect(S390CcwMachineState *ms)
ms->pv = false;
migrate_del_blocker(pv_mig_blocker);
error_free_or_abort(&pv_mig_blocker);
- qemu_balloon_inhibit(false);
+ ram_block_discard_disable(false);
}
static int s390_machine_protect(S390CcwMachineState *ms)
@@ -338,17 +337,22 @@ static int s390_machine_protect(S390CcwMachineState *ms)
int rc;
/*
- * Ballooning on protected VMs needs support in the guest for
- * sharing and unsharing balloon pages. Block ballooning for
- * now, until we have a solution to make at least Linux guests
- * either support it or fail gracefully.
+ * Discarding of memory in RAM blocks does not work as expected with
+ * protected VMs. Sharing and unsharing pages would be required. Disable
+ * it for now, until until we have a solution to make at least Linux
+ * guests either support it (e.g., virtio-balloon) or fail gracefully.
*/
- qemu_balloon_inhibit(true);
+ rc = ram_block_discard_disable(true);
+ if (rc) {
+ error_report("protected VMs: cannot disable RAM discard");
+ return rc;
+ }
+
error_setg(&pv_mig_blocker,
"protected VMs are currently not migrateable.");
rc = migrate_add_blocker(pv_mig_blocker, &local_err);
if (rc) {
- qemu_balloon_inhibit(false);
+ ram_block_discard_disable(false);
error_report_err(local_err);
error_free_or_abort(&pv_mig_blocker);
return rc;
@@ -357,7 +361,7 @@ static int s390_machine_protect(S390CcwMachineState *ms)
/* Create SE VM */
rc = s390_pv_vm_enable();
if (rc) {
- qemu_balloon_inhibit(false);
+ ram_block_discard_disable(false);
migrate_del_blocker(pv_mig_blocker);
error_free_or_abort(&pv_mig_blocker);
return rc;
--
2.25.4
next prev parent reply other threads:[~2020-05-20 12:32 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-05-20 12:31 [PATCH v2 00/19] virtio-mem: Paravirtualized memory hot(un)plug David Hildenbrand
2020-05-20 12:31 ` [PATCH v2 01/19] exec: Introduce ram_block_discard_(disable|require)() David Hildenbrand
2020-05-20 12:31 ` [PATCH v2 02/19] vfio: Convert to ram_block_discard_disable() David Hildenbrand
2020-05-20 12:31 ` [PATCH v2 03/19] accel/kvm: " David Hildenbrand
2020-05-20 13:00 ` Philippe Mathieu-Daudé
2020-05-20 13:01 ` David Hildenbrand
2020-05-20 12:31 ` David Hildenbrand [this message]
2020-05-20 12:31 ` [PATCH v2 05/19] virtio-balloon: Rip out qemu_balloon_inhibit() David Hildenbrand
2020-05-20 12:31 ` [PATCH v2 06/19] target/i386: sev: Use ram_block_discard_disable() David Hildenbrand
2020-05-20 12:31 ` [PATCH v2 07/19] migration/rdma: " David Hildenbrand
2020-05-20 15:52 ` Dr. David Alan Gilbert
2020-05-20 12:31 ` [PATCH v2 08/19] migration/colo: " David Hildenbrand
2020-05-20 12:31 ` [PATCH v2 09/19] linux-headers: update to contain virtio-mem David Hildenbrand
2020-05-20 12:31 ` [PATCH v2 10/19] virtio-mem: Paravirtualized memory hot(un)plug David Hildenbrand
2020-05-20 12:31 ` [PATCH v2 11/19] virtio-pci: Proxy for virtio-mem David Hildenbrand
2020-05-20 12:31 ` [PATCH v2 12/19] MAINTAINERS: Add myself as virtio-mem maintainer David Hildenbrand
2020-05-20 16:01 ` Dr. David Alan Gilbert
2020-05-20 12:31 ` [PATCH v2 13/19] hmp: Handle virtio-mem when printing memory device info David Hildenbrand
2020-05-20 12:31 ` [PATCH v2 14/19] numa: Handle virtio-mem in NUMA stats David Hildenbrand
2020-05-20 12:31 ` [PATCH v2 15/19] pc: Support for virtio-mem-pci David Hildenbrand
2020-05-20 12:31 ` [PATCH v2 16/19] virtio-mem: Allow notifiers for size changes David Hildenbrand
2020-05-20 12:31 ` [PATCH v2 17/19] virtio-pci: Send qapi events when the virtio-mem " David Hildenbrand
2020-05-20 12:31 ` [PATCH v2 18/19] virtio-mem: Migration sanity checks David Hildenbrand
2020-05-20 12:31 ` [PATCH v2 19/19] virtio-mem: Add trace events David Hildenbrand
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=20200520123152.60527-5-david@redhat.com \
--to=david@redhat.com \
--cc=borntraeger@de.ibm.com \
--cc=cohuck@redhat.com \
--cc=dgilbert@redhat.com \
--cc=ehabkost@redhat.com \
--cc=frankja@linux.ibm.com \
--cc=kvm@vger.kernel.org \
--cc=mst@redhat.com \
--cc=pasic@linux.ibm.com \
--cc=pbonzini@redhat.com \
--cc=qemu-devel@nongnu.org \
--cc=qemu-s390x@nongnu.org \
--cc=rth@twiddle.net \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).