* [PATCH] migration: only check page size match if RAM postcopy is enabled
@ 2021-02-04 16:35 Stefan Reiter
2021-02-04 16:55 ` Dr. David Alan Gilbert
2021-02-08 10:59 ` Dr. David Alan Gilbert
0 siblings, 2 replies; 3+ messages in thread
From: Stefan Reiter @ 2021-02-04 16:35 UTC (permalink / raw)
To: Vladimir Sementsov-Ogievskiy, Juan Quintela,
Dr. David Alan Gilbert
Cc: qemu-devel
Postcopy may also be advised for dirty-bitmap migration only, in which
case the remote page size will not be available and we'll instead read
bogus data, blocking migration with a mismatch error if the VM uses
hugepages.
Fixes: 58110f0acb ("migration: split common postcopy out of ram postcopy")
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
---
migration/ram.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/migration/ram.c b/migration/ram.c
index 7811cde643..6ace15261c 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -3521,7 +3521,7 @@ static int ram_load_precopy(QEMUFile *f)
}
}
/* For postcopy we need to check hugepage sizes match */
- if (postcopy_advised &&
+ if (postcopy_advised && migrate_postcopy_ram() &&
block->page_size != qemu_host_page_size) {
uint64_t remote_page_size = qemu_get_be64(f);
if (remote_page_size != block->page_size) {
--
2.20.1
^ permalink raw reply related [flat|nested] 3+ messages in thread* Re: [PATCH] migration: only check page size match if RAM postcopy is enabled
2021-02-04 16:35 [PATCH] migration: only check page size match if RAM postcopy is enabled Stefan Reiter
@ 2021-02-04 16:55 ` Dr. David Alan Gilbert
2021-02-08 10:59 ` Dr. David Alan Gilbert
1 sibling, 0 replies; 3+ messages in thread
From: Dr. David Alan Gilbert @ 2021-02-04 16:55 UTC (permalink / raw)
To: Stefan Reiter; +Cc: Vladimir Sementsov-Ogievskiy, qemu-devel, Juan Quintela
* Stefan Reiter (s.reiter@proxmox.com) wrote:
> Postcopy may also be advised for dirty-bitmap migration only, in which
> case the remote page size will not be available and we'll instead read
> bogus data, blocking migration with a mismatch error if the VM uses
> hugepages.
>
> Fixes: 58110f0acb ("migration: split common postcopy out of ram postcopy")
> Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
Ah! That would explain a report on qemu-discuss a few days ago; yes this
makes sense.
(However you've literally just missed a migration pull; next time!)
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
> ---
> migration/ram.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/migration/ram.c b/migration/ram.c
> index 7811cde643..6ace15261c 100644
> --- a/migration/ram.c
> +++ b/migration/ram.c
> @@ -3521,7 +3521,7 @@ static int ram_load_precopy(QEMUFile *f)
> }
> }
> /* For postcopy we need to check hugepage sizes match */
> - if (postcopy_advised &&
> + if (postcopy_advised && migrate_postcopy_ram() &&
> block->page_size != qemu_host_page_size) {
> uint64_t remote_page_size = qemu_get_be64(f);
> if (remote_page_size != block->page_size) {
> --
> 2.20.1
>
>
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: [PATCH] migration: only check page size match if RAM postcopy is enabled
2021-02-04 16:35 [PATCH] migration: only check page size match if RAM postcopy is enabled Stefan Reiter
2021-02-04 16:55 ` Dr. David Alan Gilbert
@ 2021-02-08 10:59 ` Dr. David Alan Gilbert
1 sibling, 0 replies; 3+ messages in thread
From: Dr. David Alan Gilbert @ 2021-02-08 10:59 UTC (permalink / raw)
To: Stefan Reiter; +Cc: Vladimir Sementsov-Ogievskiy, qemu-devel, Juan Quintela
* Stefan Reiter (s.reiter@proxmox.com) wrote:
> Postcopy may also be advised for dirty-bitmap migration only, in which
> case the remote page size will not be available and we'll instead read
> bogus data, blocking migration with a mismatch error if the VM uses
> hugepages.
>
> Fixes: 58110f0acb ("migration: split common postcopy out of ram postcopy")
> Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
Queued
> ---
> migration/ram.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/migration/ram.c b/migration/ram.c
> index 7811cde643..6ace15261c 100644
> --- a/migration/ram.c
> +++ b/migration/ram.c
> @@ -3521,7 +3521,7 @@ static int ram_load_precopy(QEMUFile *f)
> }
> }
> /* For postcopy we need to check hugepage sizes match */
> - if (postcopy_advised &&
> + if (postcopy_advised && migrate_postcopy_ram() &&
> block->page_size != qemu_host_page_size) {
> uint64_t remote_page_size = qemu_get_be64(f);
> if (remote_page_size != block->page_size) {
> --
> 2.20.1
>
>
>
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2021-02-08 17:36 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2021-02-04 16:35 [PATCH] migration: only check page size match if RAM postcopy is enabled Stefan Reiter
2021-02-04 16:55 ` Dr. David Alan Gilbert
2021-02-08 10:59 ` Dr. David Alan Gilbert
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).