linux/drivers/block, branch v2.6.38

block: kill loop_mutex

2011-03-03T16:53:25Z

Following steps lead to deadlock in kernel: dd if=/dev/zero of=img bs=512 count=1000 losetup -f img mkfs.ext2 /dev/loop0 mount -t ext2 -o loop /dev/loop0 mnt umount mnt/ Stacktrace: [] irq_exit+0x36/0x59 [] smp_apic_timer_interrupt+0x6b/0x75 [] apic_timer_interrupt+0x31/0x38 [] mutex_spin_on_owner+0x54/0x5b [] lo_release+0x12/0x67 [loop] [] __blkdev_put+0x7c/0x10c [] fput+0xd5/0x1aa [] loop_clr_fd+0x1a9/0x1b1 [loop] [] lo_release+0x39/0x67 [loop] [] __blkdev_put+0x7c/0x10c [] deactivate_locked_super+0x17/0x36 [] sys_umount+0x27e/0x2a5 [] sys_oldumount+0xb/0xe [] sysenter_do_call+0x12/0x26 [] 0xffffffff Regression since 2a48fc0ab24241755dc9, which introduced the private loop_mutex as part of the BKL removal process. As per [1], the mutex can be safely removed. [1] http://www.gossamer-threads.com/lists/linux/kernel/1341930 Addresses: https://bugzilla.novell.com/show_bug.cgi?id=669394 Addresses: https://bugzilla.kernel.org/show_bug.cgi?id=29172 Signed-off-by: Petr Uzel Cc: stable@kernel.org Reviewed-by: Nikanth Karthikesan Acked-by: Arnd Bergmann Signed-off-by: Jens Axboe

Merge branch 'for-linus' of git://neil.brown.name/md

2011-02-25T19:13:26Z

* 'for-linus' of git://neil.brown.name/md: md: Fix - again - partition detection when array becomes active Fix over-zealous flush_disk when changing device size. md: avoid spinlock problem in blk_throtl_exit md: correctly handle probe of an 'mdp' device. md: don't set_capacity before array is active. md: Fix raid1->raid0 takeover

Fix over-zealous flush_disk when changing device size.

2011-02-24T06:25:47Z

There are two cases when we call flush_disk. In one, the device has disappeared (check_disk_change) so any data will hold becomes irrelevant. In the oter, the device has changed size (check_disk_size_change) so data we hold may be irrelevant. In both cases it makes sense to discard any 'clean' buffers, so they will be read back from the device if needed. In the former case it makes sense to discard 'dirty' buffers as there will never be anywhere safe to write the data. In the second case it *does*not* make sense to discard dirty buffers as that will lead to file system corruption when you simply enlarge the containing devices. flush_disk calls __invalidate_devices. __invalidate_device calls both invalidate_inodes and invalidate_bdev. invalidate_inodes *does* discard I_DIRTY inodes and this does lead to fs corruption. invalidate_bev *does*not* discard dirty pages, but I don't really care about that at present. So this patch adds a flag to __invalidate_device (calling it __invalidate_device2) to indicate whether dirty buffers should be killed, and this is passed to invalidate_inodes which can choose to skip dirty inodes. flusk_disk then passes true from check_disk_change and false from check_disk_size_change. dm avoids tripping over this problem by calling i_size_write directly rathher than using check_disk_size_change. md does use check_disk_size_change and so is affected. This regression was introduced by commit 608aeef17a which causes check_disk_size_change to call flush_disk, so it is suitable for any kernel since 2.6.27. Cc: stable@kernel.org Acked-by: Jeff Moyer Cc: Andrew Patterson Cc: Jens Axboe Signed-off-by: NeilBrown

nbd: remove module-level ioctl mutex

2011-02-12T00:12:20Z

Commit 2a48fc0ab242417 ("block: autoconvert trivial BKL users to private mutex") replaced uses of the BKL in the nbd driver with mutex operations. Since then, I've been been seeing these lock ups: INFO: task qemu-nbd:16115 blocked for more than 120 seconds. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. qemu-nbd D 0000000000000001 0 16115 16114 0x00000004 ffff88007d775d98 0000000000000082 ffff88007d775fd8 ffff88007d774000 0000000000013a80 ffff8800020347e0 ffff88007d775fd8 0000000000013a80 ffff880133730000 ffff880002034440 ffffea0004333db8 ffffffffa071c020 Call Trace: [] __mutex_lock_slowpath+0xf7/0x180 [] mutex_lock+0x2b/0x50 [] nbd_ioctl+0x6c/0x1c0 [nbd] [] blkdev_ioctl+0x230/0x730 [] block_ioctl+0x41/0x50 [] do_vfs_ioctl+0x93/0x370 [] sys_ioctl+0x81/0xa0 [] system_call_fastpath+0x16/0x1b Instrumenting the nbd module's ioctl handler with some extra logging clearly shows the NBD_DO_IT ioctl being invoked which is a long-lived ioctl in the sense that it doesn't return until another ioctl asks the driver to disconnect. However, that other ioctl blocks, waiting for the module-level mutex that replaced the BKL, and then we're stuck. This patch removes the module-level mutex altogether. It's clearly wrong, and as far as I can see, it's entirely unnecessary, since the nbd driver maintains per-device mutexes, and I don't see anything that would require a module-level (or kernel-level, for that matter) mutex. Signed-off-by: Soren Hansen Acked-by: Serge Hallyn Acked-by: Paul Clements Cc: Arnd Bergmann Cc: Jens Axboe Cc: [2.6.37.x] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

cciss: make cciss_revalidate not loop through CISS_MAX_LUNS volumes unnecessarily.

2011-01-19T15:25:02Z

Signed-off-by: Stephen M. Cameron Signed-off-by: Andrew Morton Signed-off-by: Jens Axboe

drivers/block/aoe/Makefile: replace the use of -objs with -y

2011-01-19T15:25:02Z

Change Makefile to use -y instead of -objs because -objs is deprecated and should now be switched. According to (documentation/kbuild/makefiles.txt). Signed-off-by: Tracey Dent Cc: "Ed L. Cashin" Signed-off-by: Andrew Morton Signed-off-by: Jens Axboe

loop: queue_lock NULL pointer derefence in blk_throtl_exit

2011-01-19T15:25:02Z

Performing $ sudo mount -o loop -o umask=0 /dev/sdb1 /mnt/ mount: wrong fs type, bad option, bad superblock on /dev/loop0, missing codepage or helper program, or other error In some cases useful info is found in syslog - try dmesg | tail or so $ sudo modprobe -r loop results in oops: BUG: unable to handle kernel NULL pointer dereference at 0000000000000004 IP: [] do_raw_spin_lock+0x14/0x122 Process modprobe (pid: 6189, threadinfo ffff88009a898000, task ffff880154a88000) Call Trace: [] _raw_spin_lock_irq+0x4a/0x51 [] ? blk_throtl_exit+0x3b/0xa0 [] ? cancel_delayed_work_sync+0xd/0xf [] blk_throtl_exit+0x3b/0xa0 [] blk_release_queue+0x21/0x65 [] kobject_release+0x51/0x66 [] ? kobject_release+0x0/0x66 [] kref_put+0x43/0x4d [] kobject_put+0x47/0x4b [] blk_cleanup_queue+0x56/0x5b [] loop_exit+0x68/0x844 [loop] [] sys_delete_module+0x1e8/0x25b [] ? trace_hardirqs_on_thunk+0x3a/0x3f [] system_call_fastpath+0x16/0x1b because of an attempt to acquire NULL queue_lock. I added the same lines as in blk_queue_make_request - index 44e18c0..49e6a54 100644`fall back to embedded per-queue lock'. Signed-off-by: Sergey Senozhatsky Signed-off-by: Andrew Morton Signed-off-by: Jens Axboe

drivers/block/Makefile: replace the use of -objs with -y

2011-01-19T15:25:02Z

Change Makefile to use -y instead of -objs because -objs is deprecated and should now be switched. According to (documentation/kbuild/makefiles.txt). Signed-off-by: Tracey Dent Signed-off-by: Andrew Morton Signed-off-by: Jens Axboe

Merge branch 'for-2.6.38/drivers' of git://git.kernel.dk/linux-2.6-block

2011-01-13T18:50:24Z

* 'for-2.6.38/drivers' of git://git.kernel.dk/linux-2.6-block: cciss: reinstate proper FIFO order of command queue list floppy: replace NO_GEOM macro with a function

Merge branch 'for-2.6.38/core' of git://git.kernel.dk/linux-2.6-block

2011-01-13T18:45:01Z

* 'for-2.6.38/core' of git://git.kernel.dk/linux-2.6-block: (43 commits) block: ensure that completion error gets properly traced blktrace: add missing probe argument to block_bio_complete block cfq: don't use atomic_t for cfq_group block cfq: don't use atomic_t for cfq_queue block: trace event block fix unassigned field block: add internal hd part table references block: fix accounting bug on cross partition merges kref: add kref_test_and_get bio-integrity: mark kintegrityd_wq highpri and CPU intensive block: make kblockd_workqueue smarter Revert "sd: implement sd_check_events()" block: Clean up exit_io_context() source code. Fix compile warnings due to missing removal of a 'ret' variable fs/block: type signature of major_to_index(int) to major_to_index(unsigned) block: convert !IS_ERR(p) && p to !IS_ERR_NOR_NULL(p) cfq-iosched: don't check cfqg in choose_service_tree() fs/splice: Pull buf->ops->confirm() from splice_from_pipe actors cdrom: export cdrom_check_events() sd: implement sd_check_events() sr: implement sr_check_events() ...