[PATCH 5.14 003/168] swiotlb-xen: fix late init retry

[Greg Kroah-Hartman]

From: Jan Beulich <jbeulich@xxxxxxxx>

commit 4c092c59015f7adf0f07685f869edb96d997a756 upstream.

The commit referenced below removed the assignment of "bytes" from
xen_swiotlb_init() without - like done for xen_swiotlb_init_early() -
adding an assignment on the retry path, thus leading to excessively
sized allocations upon retries.

Fixes: 2d29960af0be ("swiotlb: dynamically allocate io_tlb_default_mem")
Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

Link: https://lore.kernel.org/r/778299d6-9cfd-1c13-026e-25ee5d14ecb3@xxxxxxxx
Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
---
 drivers/xen/swiotlb-xen.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/xen/swiotlb-xen.c
+++ b/drivers/xen/swiotlb-xen.c
@@ -211,8 +211,8 @@ error:
 	if (repeat--) {
 		/* Min is 2MB */
 		nslabs = max(1024UL, (nslabs >> 1));
-		pr_info("Lowering to %luMB\n",
-			(nslabs << IO_TLB_SHIFT) >> 20);
+		bytes = nslabs << IO_TLB_SHIFT;
+		pr_info("Lowering to %luMB\n", bytes >> 20);
 		goto retry;
 	}
 	pr_err("%s (rc:%d)\n", xen_swiotlb_error(m_ret), rc);