[xen master] libs/guest: Allocate rec_pfns earlier in write_batch()

[patchbot@xxxxxxx]

commit 72927fc6f7e87b8f791022e78a618bb6a66e5361
Author:     Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
AuthorDate: Wed Jul 1 14:27:39 2026 +0100
Commit:     Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
CommitDate: Wed Jul 8 15:35:45 2026 +0100

    libs/guest: Allocate rec_pfns earlier in write_batch()
    
    For reasons which escape me, rec_pfns are allocated separately to the rest 
of
    the batch allocations.
    
    Allocate them all together.  This will allow for future simplifications to 
be
    performed in an incremental mannor.
    
    No functional change.
    
    Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
    Reviewed-by: Anthony PERARD <anthony.perard@xxxxxxxxxx>
---
 tools/libs/guest/xg_sr_save.c | 14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)

diff --git a/tools/libs/guest/xg_sr_save.c b/tools/libs/guest/xg_sr_save.c
index 6f310d6d8c..185ef80e1f 100644
--- a/tools/libs/guest/xg_sr_save.c
+++ b/tools/libs/guest/xg_sr_save.c
@@ -115,8 +115,10 @@ static int write_batch(struct xc_sr_context *ctx)
     local_pages = calloc(nr_pfns, sizeof(*local_pages));
     /* iovec[] for writev(). */
     iov = malloc((nr_pfns + 4) * sizeof(*iov));
+    /* page_data record PFNs list */
+    rec_pfns = malloc(nr_pfns * sizeof(*rec_pfns));
 
-    if ( !mfns || !types || !errors || !guest_data || !local_pages || !iov )
+    if ( !mfns || !types || !errors || !guest_data || !local_pages || !iov || 
!rec_pfns )
     {
         ERROR("Unable to allocate arrays for a batch of %u pages",
               nr_pfns);
@@ -207,14 +209,6 @@ static int write_batch(struct xc_sr_context *ctx)
         }
     }
 
-    rec_pfns = malloc(nr_pfns * sizeof(*rec_pfns));
-    if ( !rec_pfns )
-    {
-        ERROR("Unable to allocate %zu bytes of memory for page data pfn list",
-              nr_pfns * sizeof(*rec_pfns));
-        goto err;
-    }
-
     hdr.count = nr_pfns;
 
     rec.length = sizeof(hdr);
@@ -263,11 +257,11 @@ static int write_batch(struct xc_sr_context *ctx)
     rc = ctx->save.nr_batch_pfns = 0;
 
  err:
-    free(rec_pfns);
     if ( guest_mapping )
         xenforeignmemory_unmap(xch->fmem, guest_mapping, nr_pages_mapped);
     for ( i = 0; local_pages && i < nr_pfns; ++i )
         free(local_pages[i]);
+    free(rec_pfns);
     free(iov);
     free(local_pages);
     free(guest_data);
--
generated by git-patchbot for /home/xen/git/xen.git#master