diff options
| author | Thomas Huth <thuth@redhat.com> | 2016-11-04 14:10:17 +0100 |
|---|---|---|
| committer | Juan Quintela <quintela@redhat.com> | 2016-11-14 19:35:41 +0100 |
| commit | 5c90308f07335451a08c030dc40a9eed4698152b (patch) | |
| tree | dc4d3d53f0bfe221e259dacde554ece51fa1ca3b /migration | |
| parent | 8cc49f0302ff23353034b6f9cbf4e5d778239a3d (diff) | |
migration: Fix return code of ram_save_iterate()
qemu_savevm_state_iterate() expects the iterators to return 1
when they are done, and 0 if there is still something left to do.
However, ram_save_iterate() does not obey this rule and returns
the number of saved pages instead. This causes a fatal hang with
ppc64 guests when you run QEMU like this (also works with TCG):
qemu-img create -f qcow2 /tmp/test.qcow2 1M
qemu-system-ppc64 -nographic -nodefaults -m 256 \
-hda /tmp/test.qcow2 -serial mon:stdio
... then switch to the monitor by pressing CTRL-a c and try to
save a snapshot with "savevm test1" for example.
After the first iteration, ram_save_iterate() always returns 0 here,
so that qemu_savevm_state_iterate() hangs in an endless loop and you
can only "kill -9" the QEMU process.
Fix it by using proper return values in ram_save_iterate().
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Diffstat (limited to 'migration')
| -rw-r--r-- | migration/ram.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/migration/ram.c b/migration/ram.c index fb9252d722..a1c8089010 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -1987,7 +1987,7 @@ static int ram_save_iterate(QEMUFile *f, void *opaque) int ret; int i; int64_t t0; - int pages_sent = 0; + int done = 0; rcu_read_lock(); if (ram_list.version != last_version) { @@ -2007,9 +2007,9 @@ static int ram_save_iterate(QEMUFile *f, void *opaque) pages = ram_find_and_save_block(f, false, &bytes_transferred); /* no more pages to sent */ if (pages == 0) { + done = 1; break; } - pages_sent += pages; acct_info.iterations++; /* we want to check in the 1st loop, just in case it was the 1st time @@ -2044,7 +2044,7 @@ static int ram_save_iterate(QEMUFile *f, void *opaque) return ret; } - return pages_sent; + return done; } /* Called with iothread lock */ |