From ca0354f90a25be9f4e31dafe6e37b012bb2de7ac Mon Sep 17 00:00:00 2001 From: Yang Hongyang Date: Mon, 28 Jul 2014 12:03:27 +0800 Subject: [PATCH] tools: libxc: fix Remus failover regression commit: c2ba706c "tools/libxc: goto correct label on error paths" by Andrew Cooper broke Remus in Xen 4.4 or earlier versions that has this commit backported. With Remus, this jump essentially discards the current incomplete checkpoint received by the backup and restore backup from the last complete checkpoint. This is required for Remus to work and this does not break live migration. It has been around since Xen 4.0. CC: Ian Jackson CC: Ian Campbell CC: Andrew Cooper CC: Shriram Rajagopalan Signed-off-by: Yang Hongyang Acked-by: Shriram Rajagopalan Reviewed-by: Andrew Cooper Acked-by: Ian Campbell --- tools/libxc/xc_domain_restore.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/tools/libxc/xc_domain_restore.c b/tools/libxc/xc_domain_restore.c index e73e0a22d3..b9a56d5c77 100644 --- a/tools/libxc/xc_domain_restore.c +++ b/tools/libxc/xc_domain_restore.c @@ -1783,20 +1783,29 @@ int xc_domain_restore(xc_interface *xch, int io_fd, uint32_t dom, if ( pagebuf_get(xch, ctx, &pagebuf, io_fd, dom) ) { PERROR("error when buffering batch, finishing"); - goto out; + /* + * Remus: discard the current incomplete checkpoint and restore + * backup from the last complete checkpoint. + */ + goto finish; } memset(&tmptail, 0, sizeof(tmptail)); tmptail.ishvm = hvm; if ( buffer_tail(xch, ctx, &tmptail, io_fd, max_vcpu_id, vcpumap, ext_vcpucontext, vcpuextstate_size) < 0 ) { ERROR ("error buffering image tail, finishing"); - goto out; + /* + * Remus: discard the current incomplete checkpoint and restore + * backup from the last complete checkpoint. + */ + goto finish; } tailbuf_free(&tailbuf); memcpy(&tailbuf, &tmptail, sizeof(tailbuf)); goto loadpages; + /* With Remus: restore from last complete checkpoint */ finish: if ( hvm ) goto finish_hvm; -- 2.30.2