From 2fc136eecd0c647a6b13fcd00d0c41a1a28f35a5 Mon Sep 17 00:00:00 2001 From: Stefano Stabellini Date: Wed, 12 Sep 2012 12:44:30 +0100 Subject: xen/m2p: do not reuse kmap_op->dev_bus_addr If the caller passes a valid kmap_op to m2p_add_override, we use kmap_op->dev_bus_addr to store the original mfn, but dev_bus_addr is part of the interface with Xen and if we are batching the hypercalls it might not have been written by the hypervisor yet. That means that later on Xen will write to it and we'll think that the original mfn is actually what Xen has written to it. Rather than "stealing" struct members from kmap_op, keep using page->index to store the original mfn and add another parameter to m2p_remove_override to get the corresponding kmap_op instead. It is now responsibility of the caller to keep track of which kmap_op corresponds to a particular page in the m2p_override (gntdev, the only user of this interface that passes a valid kmap_op, is already doing that). CC: stable@kernel.org Reported-and-Tested-By: Sander Eikelenboom Signed-off-by: Stefano Stabellini Signed-off-by: Konrad Rzeszutek Wilk --- drivers/block/xen-blkback/blkback.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/block/xen-blkback') diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c index 73f196ca713f..c6decb901e5e 100644 --- a/drivers/block/xen-blkback/blkback.c +++ b/drivers/block/xen-blkback/blkback.c @@ -337,7 +337,7 @@ static void xen_blkbk_unmap(struct pending_req *req) invcount++; } - ret = gnttab_unmap_refs(unmap, pages, invcount, false); + ret = gnttab_unmap_refs(unmap, NULL, pages, invcount); BUG_ON(ret); } -- cgit v1.2.3