FAILED: patch "[PATCH] swiotlb-xen: avoid double free" failed to apply to 4.4-stable tree

The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From ce6a80d1b2f923b1839655a1cda786293feaa085 Mon Sep 17 00:00:00 2001
From: Jan Beulich <[email protected]>
Date: Tue, 7 Sep 2021 14:04:25 +0200
Subject: [PATCH] swiotlb-xen: avoid double free

Of the two paths leading to the "error" label in xen_swiotlb_init() one didn't allocate anything, while the other did already free what was allocated.

index 24d11861ac7d..99d518526eaf 100644
@@ -216,7 +216,6 @@ int __ref xen_swiotlb_init(void)
 		goto retry;
 	}
 	pr_err("%s (rc:%d)\n", xen_swiotlb_error(m_ret), rc);
-	free_pages((unsigned long)start, order);
 	return rc;
 }