From: Chang Huaixin Date: Thu, 16 Oct 2014 20:33:24 +0000 (-0700) Subject: Input: xen-kbdfront - free grant table entry in xenkbd_disconnect_backend X-Git-Tag: fixes-against-v3.18-rc2~35^2~3 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=4d544e3bdb12f8e48f61e7f2270b253a48c69e00;p=pandora-kernel.git Input: xen-kbdfront - free grant table entry in xenkbd_disconnect_backend xenkbd_disconnect_backend doesn't free grant table entry. This bug affects live migration. xenkbd_disconnect_backend uses gnttab_end_foreign_access_ref to handle grant table entry which doesn't really free an entry. Thus every time we do xenkbd_resume, grant table entry increses by one. As an grant table entry occupies 8 bytes, an grant table page has at most 512 entries. Every 512 times we do xenkdb_resume, grant table pages increses by one. After around 3500 times of live migration, grant table pages will increase by 7, causing too many pages to populate and hitting max_pages limit when assigning pages.Thus assign_pages will fail, so will live migration. Signed-off-by: Chang Huaixin Acked-by: David Vrabel Signed-off-by: Dmitry Torokhov --- Reading git-diff-tree failed