From d50babbe300eedf33ea5b00a12c5df3a05bd96c7 Mon Sep 17 00:00:00 2001 From: Bob Liu Date: Wed, 22 Jul 2015 14:40:08 +0800 Subject: [PATCH] xen-blkfront: introduce blkfront_gather_backend_features() MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit There is a bug when migrate from !feature-persistent host to feature-persistent host, because domU still thinks new host/backend doesn't support persistent. Dmesg like: backed has not unmapped grant: 839 backed has not unmapped grant: 773 backed has not unmapped grant: 773 backed has not unmapped grant: 773 backed has not unmapped grant: 839 The fix is to recheck feature-persistent of new backend in blkif_recover(). See: https://lkml.org/lkml/2015/5/25/469 As Roger suggested, we can split the part of blkfront_connect that checks for optional features, like persistent grants, indirect descriptors and flush/barrier features to a separate function and call it from both blkfront_connect and blkif_recover Acked-by: Roger Pau Monné Signed-off-by: Bob Liu Signed-off-by: Konrad Rzeszutek Wilk --- Reading git-format-patch failed