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* [Xen-4.3 backport] [Patch] tools/migrate: Fix regression when migrating from older version of Xen
@ 2013-10-10 13:56 Andrew Cooper
  2013-11-12 15:21 ` Ian Jackson
  0 siblings, 1 reply; 6+ messages in thread
From: Andrew Cooper @ 2013-10-10 13:56 UTC (permalink / raw)
  To: Xen-devel; +Cc: Andrew Cooper, Ian Jackson

Commit 00a4b65f8534c9e6521eab2e6ce796ae36037774 Sep 7 2010
  "libxc: provide notification of final checkpoint to restore end"
broke migration from any version of Xen using tools from prior to that commit

Older tools have no idea about an XC_SAVE_ID_LAST_CHECKPOINT, causing newer
tools xc_domain_restore() to start reading the qemu save record, as
ctx->last_checkpoint is 0.

The failure looks like:
  xc: error: Max batch size exceeded (1970103633). Giving up.
where 1970103633 = 0x756d6551 = *(uint32_t*)"Qemu"

With this fix in place, the behaviour for normal migrations is reverted to how
it was before the regression; the migration is considered non-checkpointed
right from the start.  A XC_SAVE_ID_LAST_CHECKPOINT chunk seen in the
migration stream is a nop.  For checkpointed migrations the behaviour is
unchanged.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Campbell <Ian.Campbell@citrix.com>
CC: Ian Jackson <Ian.Jackson@eu.citrix.com>
Acked-by: Shriram Rajagopalan <rshriram@cs.ubc.ca> (Remus bits)
master commit: 7051d5c872e3e708b2d4b2088215d6ab1b33de1b
master date: Thu, 10 Oct 2013 11:28:21 +0000

Backport to Xen-4.3:

As remus was not a supported feature in libxl in 4.3 and earlier, this
backport hardcodes a non-checkpointed stream from libxl, removing the need to
any playing around with the IDL and API.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
CC: Ian Jackson <Ian.Jackson@eu.citrix.com>
---
 tools/libxc/xc_domain_restore.c         |    3 ++-
 tools/libxc/xc_nomigrate.c              |    2 +-
 tools/libxc/xenguest.h                  |    3 ++-
 tools/libxl/libxl_save_helper.c         |    2 +-
 tools/python/xen/xend/XendCheckpoint.py |    2 +-
 tools/xcutils/xc_restore.c              |   14 +++++++++-----
 6 files changed, 16 insertions(+), 10 deletions(-)

diff --git a/tools/libxc/xc_domain_restore.c b/tools/libxc/xc_domain_restore.c
index 63d36cd..297546c 100644
--- a/tools/libxc/xc_domain_restore.c
+++ b/tools/libxc/xc_domain_restore.c
@@ -1401,7 +1401,7 @@ int xc_domain_restore(xc_interface *xch, int io_fd, uint32_t dom,
                       domid_t store_domid, unsigned int console_evtchn,
                       unsigned long *console_mfn, domid_t console_domid,
                       unsigned int hvm, unsigned int pae, int superpages,
-                      int no_incr_generationid,
+                      int no_incr_generationid, int checkpointed_stream,
                       unsigned long *vm_generationid_addr,
                       struct restore_callbacks *callbacks)
 {
@@ -1472,6 +1472,7 @@ int xc_domain_restore(xc_interface *xch, int io_fd, uint32_t dom,
 
     ctx->superpages = superpages;
     ctx->hvm = hvm;
+    ctx->last_checkpoint = !checkpointed_stream;
 
     ctxt = xc_hypercall_buffer_alloc(xch, ctxt, sizeof(*ctxt));
 
diff --git a/tools/libxc/xc_nomigrate.c b/tools/libxc/xc_nomigrate.c
index 73e7566..fb6d53e 100644
--- a/tools/libxc/xc_nomigrate.c
+++ b/tools/libxc/xc_nomigrate.c
@@ -35,7 +35,7 @@ int xc_domain_restore(xc_interface *xch, int io_fd, uint32_t dom,
                       domid_t store_domid, unsigned int console_evtchn,
                       unsigned long *console_mfn, domid_t console_domid,
                       unsigned int hvm, unsigned int pae, int superpages,
-                      int no_incr_generationid,
+                      int no_incr_generationid, int checkpointed_stream,
                       unsigned long *vm_generationid_addr,
                       struct restore_callbacks *callbacks)
 {
diff --git a/tools/libxc/xenguest.h b/tools/libxc/xenguest.h
index 4714bd2..2101810 100644
--- a/tools/libxc/xenguest.h
+++ b/tools/libxc/xenguest.h
@@ -114,6 +114,7 @@ struct restore_callbacks {
  * @parm pae non-zero if this HVM domain has PAE support enabled
  * @parm superpages non-zero to allocate guest memory with superpages
  * @parm no_incr_generationid non-zero if generation id is NOT to be incremented
+ * @parm checkpointed_stream non-zero if the far end of the stream is using checkpointing
  * @parm vm_generationid_addr returned with the address of the generation id buffer
  * @parm callbacks non-NULL to receive a callback to restore toolstack
  *       specific data
@@ -124,7 +125,7 @@ int xc_domain_restore(xc_interface *xch, int io_fd, uint32_t dom,
                       domid_t store_domid, unsigned int console_evtchn,
                       unsigned long *console_mfn, domid_t console_domid,
                       unsigned int hvm, unsigned int pae, int superpages,
-                      int no_incr_generationid,
+                      int no_incr_generationid, int checkpointed_stream,
                       unsigned long *vm_generationid_addr,
                       struct restore_callbacks *callbacks);
 /**
diff --git a/tools/libxl/libxl_save_helper.c b/tools/libxl/libxl_save_helper.c
index 772251a..8f14b8b 100644
--- a/tools/libxl/libxl_save_helper.c
+++ b/tools/libxl/libxl_save_helper.c
@@ -264,7 +264,7 @@ int main(int argc, char **argv)
         r = xc_domain_restore(xch, io_fd, dom, store_evtchn, &store_mfn,
                               store_domid, console_evtchn, &console_mfn,
                               console_domid, hvm, pae, superpages,
-                              no_incr_genidad, &genidad,
+                              no_incr_genidad, 0, &genidad,
                               &helper_restore_callbacks);
         helper_stub_restore_results(store_mfn,console_mfn,genidad,0);
         complete(r);
diff --git a/tools/python/xen/xend/XendCheckpoint.py b/tools/python/xen/xend/XendCheckpoint.py
index fa09757..a433ffa 100644
--- a/tools/python/xen/xend/XendCheckpoint.py
+++ b/tools/python/xen/xend/XendCheckpoint.py
@@ -301,7 +301,7 @@ def restore(xd, fd, dominfo = None, paused = False, relocating = False):
 
         cmd = map(str, [xen.util.auxbin.pathTo(XC_RESTORE),
                         fd, dominfo.getDomid(),
-                        store_port, console_port, int(is_hvm), pae, apic, superpages])
+                        store_port, console_port, int(is_hvm), pae, apic, superpages, 1])
         log.debug("[xc_restore]: %s", string.join(cmd))
 
         handler = RestoreInputHandler()
diff --git a/tools/xcutils/xc_restore.c b/tools/xcutils/xc_restore.c
index 35d725c..5ec90ac 100644
--- a/tools/xcutils/xc_restore.c
+++ b/tools/xcutils/xc_restore.c
@@ -19,7 +19,7 @@ int
 main(int argc, char **argv)
 {
     unsigned int domid, store_evtchn, console_evtchn;
-    unsigned int hvm, pae, apic, lflags;
+    unsigned int hvm, pae, apic, lflags, checkpointed;
     xc_interface *xch;
     int io_fd, ret;
     int superpages;
@@ -27,9 +27,9 @@ main(int argc, char **argv)
     xentoollog_level lvl;
     xentoollog_logger *l;
 
-    if ( (argc != 8) && (argc != 9) )
+    if ( !( argc >= 8 && argc <= 10) )
         errx(1, "usage: %s iofd domid store_evtchn "
-             "console_evtchn hvm pae apic [superpages]", argv[0]);
+             "console_evtchn hvm pae apic [superpages [checkpointed]]", argv[0]);
 
     lvl = XTL_DETAIL;
     lflags = XTL_STDIOSTREAM_SHOW_PID | XTL_STDIOSTREAM_HIDE_PROGRESS;
@@ -45,14 +45,18 @@ main(int argc, char **argv)
     hvm  = atoi(argv[5]);
     pae  = atoi(argv[6]);
     apic = atoi(argv[7]);
-    if ( argc == 9 )
+    if ( argc >= 9 )
 	    superpages = atoi(argv[8]);
     else
 	    superpages = !!hvm;
+    if ( argc >= 10 )
+        checkpointed = atoi(argv[9]);
+    else
+        checkpointed = 0;
 
     ret = xc_domain_restore(xch, io_fd, domid, store_evtchn, &store_mfn, 0,
                             console_evtchn, &console_mfn, 0, hvm, pae, superpages,
-                            0, NULL, NULL);
+                            0, checkpointed, NULL, NULL);
 
     if ( ret == 0 )
     {
-- 
1.7.10.4

^ permalink raw reply related	[flat|nested] 6+ messages in thread

* Re: [Xen-4.3 backport] [Patch] tools/migrate: Fix regression when migrating from older version of Xen
  2013-10-10 13:56 [Xen-4.3 backport] [Patch] tools/migrate: Fix regression when migrating from older version of Xen Andrew Cooper
@ 2013-11-12 15:21 ` Ian Jackson
  2013-11-13  9:29   ` Ian Campbell
  0 siblings, 1 reply; 6+ messages in thread
From: Ian Jackson @ 2013-11-12 15:21 UTC (permalink / raw)
  To: Andrew Cooper; +Cc: Jan Beulich, Xen-devel

Andrew Cooper writes ("[Xen-devel] [Xen-4.3 backport] [Patch] tools/migrate: Fix regression when migrating from older version of Xen"):
...
> With this fix in place, the behaviour for normal migrations is
> reverted to how it was before the regression; the migration is
> considered non-checkpointed right from the start.  A
> XC_SAVE_ID_LAST_CHECKPOINT chunk seen in the migration stream is a
> nop.  For checkpointed migrations the behaviour is unchanged.

This patch has been sitting in unstable master for a while now without
apparent problems, and the backport looks plausible.  So I have
applied your backport to staging-4.3.

I had a quick look at applying this to 4.2, too, but it didn't apply
cleanly.  If you have a version for 4.2, I'd be happy to commit it.

Thanks,
Ian.

(CC Jan with his stable maintainer hat on)

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [Xen-4.3 backport] [Patch] tools/migrate: Fix regression when migrating from older version of Xen
  2013-11-12 15:21 ` Ian Jackson
@ 2013-11-13  9:29   ` Ian Campbell
  2013-11-13 12:45     ` Andrew Cooper
  0 siblings, 1 reply; 6+ messages in thread
From: Ian Campbell @ 2013-11-13  9:29 UTC (permalink / raw)
  To: Ian Jackson; +Cc: Andrew Cooper, Xen-devel, Jan Beulich

On Tue, 2013-11-12 at 15:21 +0000, Ian Jackson wrote:
> Andrew Cooper writes ("[Xen-devel] [Xen-4.3 backport] [Patch] tools/migrate: Fix regression when migrating from older version of Xen"):
> ...
> > With this fix in place, the behaviour for normal migrations is
> > reverted to how it was before the regression; the migration is
> > considered non-checkpointed right from the start.  A
> > XC_SAVE_ID_LAST_CHECKPOINT chunk seen in the migration stream is a
> > nop.  For checkpointed migrations the behaviour is unchanged.
> 
> This patch has been sitting in unstable master for a while now without
> apparent problems, and the backport looks plausible.  So I have
> applied your backport to staging-4.3.
> 
> I had a quick look at applying this to 4.2, too, but it didn't apply
> cleanly.  If you have a version for 4.2, I'd be happy to commit it.

Does the issue existing between 4.2->4.3 migrations?

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [Xen-4.3 backport] [Patch] tools/migrate: Fix regression when migrating from older version of Xen
  2013-11-13  9:29   ` Ian Campbell
@ 2013-11-13 12:45     ` Andrew Cooper
  2013-11-14 11:47       ` Ian Jackson
  0 siblings, 1 reply; 6+ messages in thread
From: Andrew Cooper @ 2013-11-13 12:45 UTC (permalink / raw)
  To: Ian Campbell; +Cc: Jan Beulich, Ian Jackson, Xen-devel

On 13/11/13 09:29, Ian Campbell wrote:
> On Tue, 2013-11-12 at 15:21 +0000, Ian Jackson wrote:
>> Andrew Cooper writes ("[Xen-devel] [Xen-4.3 backport] [Patch] tools/migrate: Fix regression when migrating from older version of Xen"):
>> ...
>>> With this fix in place, the behaviour for normal migrations is
>>> reverted to how it was before the regression; the migration is
>>> considered non-checkpointed right from the start.  A
>>> XC_SAVE_ID_LAST_CHECKPOINT chunk seen in the migration stream is a
>>> nop.  For checkpointed migrations the behaviour is unchanged.
>> This patch has been sitting in unstable master for a while now without
>> apparent problems, and the backport looks plausible.  So I have
>> applied your backport to staging-4.3.
>>
>> I had a quick look at applying this to 4.2, too, but it didn't apply
>> cleanly.  If you have a version for 4.2, I'd be happy to commit it.
> Does the issue existing between 4.2->4.3 migrations?
>
>

The issue exists migrating across the changeset
00a4b65f8534c9e6521eab2e6ce796ae36037774

This is a supported upgrade configuration for XenServer.

I will endeavour to provide a 4.2 backport when I have enough time to do so.

~Andrew

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [Xen-4.3 backport] [Patch] tools/migrate: Fix regression when migrating from older version of Xen
  2013-11-13 12:45     ` Andrew Cooper
@ 2013-11-14 11:47       ` Ian Jackson
  2013-11-15 13:23         ` [Xen 4.2 backport] " Andrew Cooper
  0 siblings, 1 reply; 6+ messages in thread
From: Ian Jackson @ 2013-11-14 11:47 UTC (permalink / raw)
  To: Andrew Cooper; +Cc: Jan Beulich, Ian Campbell, Xen-devel

Andrew Cooper writes ("Re: [Xen-devel] [Xen-4.3 backport] [Patch] tools/migrate: Fix regression when migrating from older version of Xen"):
> On 13/11/13 09:29, Ian Campbell wrote:
> > Does the issue existing between 4.2->4.3 migrations?
> 
> The issue exists migrating across the changeset
> 00a4b65f8534c9e6521eab2e6ce796ae36037774
> 
> This is a supported upgrade configuration for XenServer.
> 
> I will endeavour to provide a 4.2 backport when I have enough time to do so.

Thanks,
Ian.

^ permalink raw reply	[flat|nested] 6+ messages in thread

* [Xen 4.2 backport] tools/migrate: Fix regression when migrating from older version of Xen
  2013-11-14 11:47       ` Ian Jackson
@ 2013-11-15 13:23         ` Andrew Cooper
  0 siblings, 0 replies; 6+ messages in thread
From: Andrew Cooper @ 2013-11-15 13:23 UTC (permalink / raw)
  To: Xen-devel; +Cc: Andrew Cooper, Ian Jackson

Commit 00a4b65f8534c9e6521eab2e6ce796ae36037774 Sep 7 2010
  "libxc: provide notification of final checkpoint to restore end"
broke migration from any version of Xen using tools from prior to that commit

Older tools have no idea about an XC_SAVE_ID_LAST_CHECKPOINT, causing newer
tools xc_domain_restore() to start reading the qemu save record, as
ctx->last_checkpoint is 0.

The failure looks like:
  xc: error: Max batch size exceeded (1970103633). Giving up.
where 1970103633 = 0x756d6551 = *(uint32_t*)"Qemu"

With this fix in place, the behaviour for normal migrations is reverted to how
it was before the regression; the migration is considered non-checkpointed
right from the start.  A XC_SAVE_ID_LAST_CHECKPOINT chunk seen in the
migration stream is a nop.  For checkpointed migrations the behaviour is
unchanged.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Campbell <Ian.Campbell@citrix.com>
CC: Ian Jackson <Ian.Jackson@eu.citrix.com>
Acked-by: Shriram Rajagopalan <rshriram@cs.ubc.ca> (Remus bits)
master commit: 7051d5c872e3e708b2d4b2088215d6ab1b33de1b
master date: Thu, 10 Oct 2013 11:28:21 +0000

Backport to Xen-4.2:

As remus was not a supported feature in libxl in 4.3 and earlier, this
backport hardcodes a non-checkpointed stream from libxl, removing the need to
any playing around with the IDL and API.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
CC: Ian Jackson <Ian.Jackson@eu.citrix.com>
---
 tools/libxc/xc_domain_restore.c         |    4 +++-
 tools/libxc/xc_nomigrate.c              |    2 +-
 tools/libxc/xenguest.h                  |    3 ++-
 tools/libxl/libxl_save_helper.c         |    2 +-
 tools/python/xen/xend/XendCheckpoint.py |    2 +-
 tools/xcutils/xc_restore.c              |   14 +++++++++-----
 6 files changed, 17 insertions(+), 10 deletions(-)

diff --git a/tools/libxc/xc_domain_restore.c b/tools/libxc/xc_domain_restore.c
index f9ed6b2..d59b043 100644
--- a/tools/libxc/xc_domain_restore.c
+++ b/tools/libxc/xc_domain_restore.c
@@ -1327,7 +1327,7 @@ int xc_domain_restore(xc_interface *xch, int io_fd, uint32_t dom,
                       domid_t store_domid, unsigned int console_evtchn,
                       unsigned long *console_mfn, domid_t console_domid,
                       unsigned int hvm, unsigned int pae, int superpages,
-                      int no_incr_generationid,
+                      int no_incr_generationid, int checkpointed_stream,
                       unsigned long *vm_generationid_addr,
                       struct restore_callbacks *callbacks)
 {
@@ -1394,6 +1394,8 @@ int xc_domain_restore(xc_interface *xch, int io_fd, uint32_t dom,
 
     memset(ctx, 0, sizeof(*ctx));
 
+    ctx->last_checkpoint = !checkpointed_stream;
+
     ctxt = xc_hypercall_buffer_alloc(xch, ctxt, sizeof(*ctxt));
 
     if ( ctxt == NULL )
diff --git a/tools/libxc/xc_nomigrate.c b/tools/libxc/xc_nomigrate.c
index 27680a4..c8df0b5 100644
--- a/tools/libxc/xc_nomigrate.c
+++ b/tools/libxc/xc_nomigrate.c
@@ -35,7 +35,7 @@ int xc_domain_restore(xc_interface *xch, int io_fd, uint32_t dom,
                       domid_t store_domid, unsigned int console_evtchn,
                       unsigned long *console_mfn, domid_t console_domid,
                       unsigned int hvm, unsigned int pae, int superpages,
-                      int no_incr_generationid,
+                      int no_incr_generationid, int checkpointed_stream,
                       unsigned long *vm_generationid_addr,
                       struct restore_callbacks *callbacks)
 {
diff --git a/tools/libxc/xenguest.h b/tools/libxc/xenguest.h
index 707e31c..49cb228 100644
--- a/tools/libxc/xenguest.h
+++ b/tools/libxc/xenguest.h
@@ -111,6 +111,7 @@ struct restore_callbacks {
  * @parm pae non-zero if this HVM domain has PAE support enabled
  * @parm superpages non-zero to allocate guest memory with superpages
  * @parm no_incr_generationid non-zero if generation id is NOT to be incremented
+ * @parm checkpointed_stream non-zero if the far end of the stream is using checkpointing
  * @parm vm_generationid_addr returned with the address of the generation id buffer
  * @parm callbacks non-NULL to receive a callback to restore toolstack
  *       specific data
@@ -121,7 +122,7 @@ int xc_domain_restore(xc_interface *xch, int io_fd, uint32_t dom,
                       domid_t store_domid, unsigned int console_evtchn,
                       unsigned long *console_mfn, domid_t console_domid,
                       unsigned int hvm, unsigned int pae, int superpages,
-                      int no_incr_generationid,
+                      int no_incr_generationid, int checkpointed_stream,
                       unsigned long *vm_generationid_addr,
                       struct restore_callbacks *callbacks);
 /**
diff --git a/tools/libxl/libxl_save_helper.c b/tools/libxl/libxl_save_helper.c
index 772251a..8f14b8b 100644
--- a/tools/libxl/libxl_save_helper.c
+++ b/tools/libxl/libxl_save_helper.c
@@ -264,7 +264,7 @@ int main(int argc, char **argv)
         r = xc_domain_restore(xch, io_fd, dom, store_evtchn, &store_mfn,
                               store_domid, console_evtchn, &console_mfn,
                               console_domid, hvm, pae, superpages,
-                              no_incr_genidad, &genidad,
+                              no_incr_genidad, 0, &genidad,
                               &helper_restore_callbacks);
         helper_stub_restore_results(store_mfn,console_mfn,genidad,0);
         complete(r);
diff --git a/tools/python/xen/xend/XendCheckpoint.py b/tools/python/xen/xend/XendCheckpoint.py
index fa09757..a433ffa 100644
--- a/tools/python/xen/xend/XendCheckpoint.py
+++ b/tools/python/xen/xend/XendCheckpoint.py
@@ -301,7 +301,7 @@ def restore(xd, fd, dominfo = None, paused = False, relocating = False):
 
         cmd = map(str, [xen.util.auxbin.pathTo(XC_RESTORE),
                         fd, dominfo.getDomid(),
-                        store_port, console_port, int(is_hvm), pae, apic, superpages])
+                        store_port, console_port, int(is_hvm), pae, apic, superpages, 1])
         log.debug("[xc_restore]: %s", string.join(cmd))
 
         handler = RestoreInputHandler()
diff --git a/tools/xcutils/xc_restore.c b/tools/xcutils/xc_restore.c
index 0235579..6b10685 100644
--- a/tools/xcutils/xc_restore.c
+++ b/tools/xcutils/xc_restore.c
@@ -19,15 +19,15 @@ int
 main(int argc, char **argv)
 {
     unsigned int domid, store_evtchn, console_evtchn;
-    unsigned int hvm, pae, apic;
+    unsigned int hvm, pae, apic, checkpointed;
     xc_interface *xch;
     int io_fd, ret;
     int superpages;
     unsigned long store_mfn, console_mfn;
 
-    if ( (argc != 8) && (argc != 9) )
+    if ( !( argc >= 8 && argc <= 10) )
         errx(1, "usage: %s iofd domid store_evtchn "
-             "console_evtchn hvm pae apic [superpages]", argv[0]);
+             "console_evtchn hvm pae apic [superpages [checkpointed]]", argv[0]);
 
     xch = xc_interface_open(0,0,0);
     if ( !xch )
@@ -40,14 +40,18 @@ main(int argc, char **argv)
     hvm  = atoi(argv[5]);
     pae  = atoi(argv[6]);
     apic = atoi(argv[7]);
-    if ( argc == 9 )
+    if ( argc >= 9 )
 	    superpages = atoi(argv[8]);
     else
 	    superpages = !!hvm;
+    if ( argc >= 10 )
+        checkpointed = atoi(argv[9]);
+    else
+        checkpointed = 0;
 
     ret = xc_domain_restore(xch, io_fd, domid, store_evtchn, &store_mfn, 0,
                             console_evtchn, &console_mfn, 0, hvm, pae, superpages,
-                            0, NULL, NULL);
+                            0, checkpointed, NULL, NULL);
 
     if ( ret == 0 )
     {
-- 
1.7.10.4

^ permalink raw reply related	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2013-11-15 13:23 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
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2013-10-10 13:56 [Xen-4.3 backport] [Patch] tools/migrate: Fix regression when migrating from older version of Xen Andrew Cooper
2013-11-12 15:21 ` Ian Jackson
2013-11-13  9:29   ` Ian Campbell
2013-11-13 12:45     ` Andrew Cooper
2013-11-14 11:47       ` Ian Jackson
2013-11-15 13:23         ` [Xen 4.2 backport] " Andrew Cooper

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