user/sven/linux.git, branch v3.2.41

Linux 3.2.41

2013-03-20T15:03:42Z

NLS: improve UTF8 -> UTF16 string conversion routine

2013-03-20T15:03:41Z

commit 0720a06a7518c9d0c0125bd5d1f3b6264c55c3dd upstream. The utf8s_to_utf16s conversion routine needs to be improved. Unlike its utf16s_to_utf8s sibling, it doesn't accept arguments specifying the maximum length of the output buffer or the endianness of its 16-bit output. This patch (as1501) adds the two missing arguments, and adjusts the only two places in the kernel where the function is called. A follow-on patch will add a third caller that does utilize the new capabilities. The two conversion routines are still annoyingly inconsistent in the way they handle invalid byte combinations. But that's a subject for a different patch. Signed-off-by: Alan Stern CC: Clemens Ladisch Signed-off-by: Greg Kroah-Hartman Signed-off-by: Ben Hutchings

btrfs: use rcu_barrier() to wait for bdev puts at unmount

2013-03-20T15:03:41Z

commit bc178622d40d87e75abc131007342429c9b03351 upstream. Doing this would reliably fail with -EBUSY for me: # mount /dev/sdb2 /mnt/scratch; umount /mnt/scratch; mkfs.btrfs -f /dev/sdb2 ... unable to open /dev/sdb2: Device or resource busy because mkfs.btrfs tries to open the device O_EXCL, and somebody still has it. Using systemtap to track bdev gets & puts shows a kworker thread doing a blkdev put after mkfs attempts a get; this is left over from the unmount path: btrfs_close_devices __btrfs_close_devices call_rcu(&device->rcu, free_device); free_device INIT_WORK(&device->rcu_work, __free_device); schedule_work(&device->rcu_work); so unmount might complete before __free_device fires & does its blkdev_put. Adding an rcu_barrier() to btrfs_close_devices() causes unmount to wait until all blkdev_put()s are done, and the device is truly free once unmount completes. Signed-off-by: Eric Sandeen Signed-off-by: Josef Bacik Signed-off-by: Chris Mason Signed-off-by: Ben Hutchings

loopdev: remove an user triggerable oops

2013-03-20T15:03:40Z

commit b1a6650406875b9097a032eed89af50682fe1160 upstream. When loopdev is built as module and we pass an invalid parameter, loop_init() will return directly without deregister misc device, which will cause an oops when insert loop module next time because we left some garbage in the misc device list. Test case: sudo modprobe loop max_part=1024 (failed due to invalid parameter) sudo modprobe loop (oops) Clean up nicely to avoid such oops. Signed-off-by: Guo Chao Cc: Alexander Viro Cc: Guo Chao Cc: M. Hindess Cc: Nikanth Karthikesan Cc: Jens Axboe Signed-off-by: Andrew Morton Signed-off-by: Jens Axboe Signed-off-by: Ben Hutchings

loopdev: fix a deadlock

2013-03-20T15:03:40Z

commit 5370019dc2d2c2ff90e95d181468071362934f3a upstream. bd_mutex and lo_ctl_mutex can be held in different order. Path #1: blkdev_open blkdev_get __blkdev_get (hold bd_mutex) lo_open (hold lo_ctl_mutex) Path #2: blkdev_ioctl lo_ioctl (hold lo_ctl_mutex) lo_set_capacity (hold bd_mutex) Lockdep does not report it, because path #2 actually holds a subclass of lo_ctl_mutex. This subclass seems creep into the code by mistake. The patch author actually just mentioned it in the changelog, see commit f028f3b2 ("loop: fix circular locking in loop_clr_fd()"), also see: http://marc.info/?l=linux-kernel&m=123806169129727&w=2 Path #2 hold bd_mutex to call bd_set_size(), I've protected it with i_mutex in a previous patch, so drop bd_mutex at this site. Signed-off-by: Guo Chao Cc: Alexander Viro Cc: Guo Chao Cc: M. Hindess Cc: Nikanth Karthikesan Cc: Jens Axboe Signed-off-by: Andrew Morton Signed-off-by: Jens Axboe Signed-off-by: Ben Hutchings

block: use i_size_write() in bd_set_size()

2013-03-20T15:03:40Z

commit d646a02a9d44d1421f273ae3923d97b47b918176 upstream. blkdev_ioctl(GETBLKSIZE) uses i_size_read() to read size of block device. If we update block size directly, reader may see intermediate result in some machines and configurations. Use i_size_write() instead. Signed-off-by: Guo Chao Cc: Alexander Viro Cc: Guo Chao Cc: M. Hindess Cc: Nikanth Karthikesan Cc: Jens Axboe Signed-off-by: Andrew Morton Signed-off-by: Jens Axboe Signed-off-by: Ben Hutchings

xen-netfront: delay gARP until backend switches to Connected

2013-03-20T15:03:39Z

commit 08e34eb14fe4cfd934b5c169a7682a969457c4ea upstream. After a guest is live migrated, the xen-netfront driver emits a gratuitous ARP message, so that networking hardware on the target host's subnet can take notice, and public routing to the guest is re-established. However, if the packet appears on the backend interface before the backend is added to the target host's bridge, the packet is lost, and the migrated guest's peers become unable to talk to the guest. A sufficient two-parts condition to prevent the above is: (1) ensure that the backend only moves to Connected xenbus state after its hotplug scripts completed, ie. the netback interface got added to the bridge; and (2) ensure the frontend only queues the gARP when it sees the backend move to Connected. These two together provide complete ordering. Sub-condition (1) is already satisfied by commit f942dc2552b8 in Linus' tree, based on commit 6b0b80ca7165 from [1]. In general, the full condition is sufficient, not necessary, because, according to [2], live migration has been working for a long time without satisfying sub-condition (2). However, after 6b0b80ca7165 was backported to the RHEL-5 host to ensure (1), (2) still proved necessary in the RHEL-6 guest. This patch intends to provide (2) for upstream. The Reviewed-by line comes from [3]. [1] git://xenbits.xen.org/people/ianc/linux-2.6.git#upstream/dom0/backend/netback-history [2] http://old-list-archives.xen.org/xen-devel/2011-06/msg01969.html [3] http://old-list-archives.xen.org/xen-devel/2011-07/msg00484.html Signed-off-by: Laszlo Ersek Reviewed-by: Ian Campbell Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings

mm/hotplug: correctly add new zone to all other nodes' zone lists

2013-03-20T15:03:39Z

commit 08dff7b7d629807dbb1f398c68dd9cd58dd657a1 upstream. When online_pages() is called to add new memory to an empty zone, it rebuilds all zone lists by calling build_all_zonelists(). But there's a bug which prevents the new zone to be added to other nodes' zone lists. online_pages() { build_all_zonelists() ..... node_set_state(zone_to_nid(zone), N_HIGH_MEMORY) } Here the node of the zone is put into N_HIGH_MEMORY state after calling build_all_zonelists(), but build_all_zonelists() only adds zones from nodes in N_HIGH_MEMORY state to the fallback zone lists. build_all_zonelists() ->__build_all_zonelists() ->build_zonelists() ->find_next_best_node() ->for_each_node_state(n, N_HIGH_MEMORY) So memory in the new zone will never be used by other nodes, and it may cause strange behavor when system is under memory pressure. So put node into N_HIGH_MEMORY state before calling build_all_zonelists(). Signed-off-by: Jianguo Wu Signed-off-by: Jiang Liu Cc: Mel Gorman Cc: Michal Hocko Cc: Minchan Kim Cc: Rusty Russell Cc: Yinghai Lu Cc: Tony Luck Cc: KAMEZAWA Hiroyuki Cc: KOSAKI Motohiro Cc: David Rientjes Cc: Keping Chen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings

batman-adv: Only write requested number of byte to user buffer

2013-03-20T15:03:39Z

commit b5a1eeef04cc7859f34dec9b72ea1b28e4aba07c upstream. Don't write more than the requested number of bytes of an batman-adv icmp packet to the userspace buffer. Otherwise unrelated userspace memory might get overridden by the kernel. Signed-off-by: Sven Eckelmann Signed-off-by: Marek Lindner Signed-off-by: Ben Hutchings

batman-adv: bat_socket_read missing checks

2013-03-20T15:03:39Z

commit c00b6856fc642b234895cfabd15b289e76726430 upstream. Writing a icmp_packet_rr and then reading icmp_packet can lead to kernel memory corruption, if __user *buf is just below TASK_SIZE. Signed-off-by: Paul Kot [sven@narfation.org: made it checkpatch clean] Signed-off-by: Sven Eckelmann Signed-off-by: Marek Lindner Signed-off-by: Ben Hutchings