kernel/linux.git/block/genhd.c, branch v4.0.8

block: discard bdi_unregister() in favour of bdi_destroy()

2015-06-23T00:03:29+00:00

commit aad653a0bc09dd4ebcb5579f9f835bbae9ef2ba3 upstream. bdi_unregister() now contains very little functionality. It contains a "WARN_ON" if bdi->dev is NULL. This warning is of no real consequence as bdi->dev isn't needed by anything else in the function, and it triggers if blk_cleanup_queue() -> bdi_destroy() is called before bdi_unregister, which happens since Commit: 6cd18e711dd8 ("block: destroy bdi before blockdev is unregistered.") So this isn't wanted. It also calls bdi_set_min_ratio(). This needs to be called after writes through the bdi have all been flushed, and before the bdi is destroyed. Calling it early is better than calling it late as it frees up a global resource. Calling it immediately after bdi_wb_shutdown() in bdi_destroy() perfectly fits these requirements. So bdi_unregister() can be discarded with the important content moved to bdi_destroy(), as can the writeback_bdi_unregister event which is already not used. Reported-by: Mike Snitzer Fixes: c4db59d31e39 ("fs: don't reassign dirty inodes to default_backing_dev_info") Fixes: 6cd18e711dd8 ("block: destroy bdi before blockdev is unregistered.") Acked-by: Peter Zijlstra (Intel) Acked-by: Dan Williams Tested-by: Nicholas Moulin Signed-off-by: NeilBrown Reviewed-by: Christoph Hellwig Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

block: fix ext_dev_lock lockdep report

2015-06-23T00:03:28+00:00

commit 4d66e5e9b6d720d8463e11d027bd4ad91c8b1318 upstream. ================================= [ INFO: inconsistent lock state ] 4.1.0-rc7+ #217 Tainted: G O --------------------------------- inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. swapper/6/0 [HC0[0]:SC1[1]:HE1:SE0] takes: (ext_devt_lock){+.?...}, at: [] blk_free_devt+0x3c/0x70 {SOFTIRQ-ON-W} state was registered at: [] __lock_acquire+0x461/0x1e70 [] lock_acquire+0xb7/0x290 [] _raw_spin_lock+0x38/0x50 [] blk_alloc_devt+0x6d/0xd0 <-- take the lock in process context [..] [] __lock_acquire+0x3fe/0x1e70 [] ? __lock_acquire+0xe5d/0x1e70 [] lock_acquire+0xb7/0x290 [] ? blk_free_devt+0x3c/0x70 [] _raw_spin_lock+0x38/0x50 [] ? blk_free_devt+0x3c/0x70 [] blk_free_devt+0x3c/0x70 <-- take the lock in softirq [] part_release+0x1c/0x50 [] device_release+0x36/0xb0 [] kobject_cleanup+0x7b/0x1a0 [] kobject_put+0x30/0x70 [] put_device+0x17/0x20 [] delete_partition_rcu_cb+0x16c/0x180 [] ? read_dev_sector+0xa0/0xa0 [] rcu_process_callbacks+0x2ff/0xa90 [] ? rcu_process_callbacks+0x2bf/0xa90 [] __do_softirq+0xde/0x600 Neil sees this in his tests and it also triggers on pmem driver unbind for the libnvdimm tests. This fix is on top of an initial fix by Keith for incorrect usage of mutex_lock() in this path: 2da78092dda1 "block: Fix dev_t minor allocation lifetime". Both this and 2da78092dda1 are candidates for -stable. Fixes: 2da78092dda1 ("block: Fix dev_t minor allocation lifetime") Cc: Keith Busch Reported-by: NeilBrown Signed-off-by: Dan Williams Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

genhd: check for int overflow in disk_expand_part_tbl()

2014-11-19T20:09:07+00:00

We can get here from blkdev_ioctl() -> blkpg_ioctl() -> add_partition() with a user passed in partno value. If we pass in 0x7fffffff, the new target in disk_expand_part_tbl() overflows the 'int' and we access beyond the end of ptbl->part[] and even write to it when we do the rcu_assign_pointer() to assign the new partition. Reported-by: David Ramos Cc: stable@kernel.org Signed-off-by: Jens Axboe

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial

2014-10-08T01:16:26+00:00

Pull "trivial tree" updates from Jiri Kosina: "Usual pile from trivial tree everyone is so eagerly waiting for" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (39 commits) Remove MN10300_PROC_MN2WS0038 mei: fix comments treewide: Fix typos in Kconfig kprobes: update jprobe_example.c for do_fork() change Documentation: change "&" to "and" in Documentation/applying-patches.txt Documentation: remove obsolete pcmcia-cs from Changes Documentation: update links in Changes Documentation: Docbook: Fix generated DocBook/kernel-api.xml score: Remove GENERIC_HAS_IOMAP gpio: fix 'CONFIG_GPIO_IRQCHIP' comments tty: doc: Fix grammar in serial/tty dma-debug: modify check_for_stack output treewide: fix errors in printk genirq: fix reference in devm_request_threaded_irq comment treewide: fix synchronize_rcu() in comments checkstack.pl: port to AArch64 doc: queue-sysfs: minor fixes init/do_mounts: better syntax description MIPS: fix comment spelling powerpc/simpleboot: fix comment ...

genhd: fix leftover might_sleep() in blk_free_devt()

2014-09-22T20:45:45+00:00

Commit 2da78092 changed the locking from a mutex to a spinlock, so we now longer sleep in this context. But there was a leftover might_sleep() in there, which now triggers since we do the final free from an RCU callback. Get rid of it. Reported-by: Pontus Fuchs Signed-off-by: Jens Axboe

Documentation: Docbook: Fix generated DocBook/kernel-api.xml

2014-09-09T08:34:56+00:00

This patch fix spelling typo found in DocBook/kernel-api.xml. It is because the file is generated from the source comments, I have to fix the comments in source codes. Signed-off-by: Masanari Iida Acked-by: Randy Dunlap Signed-off-by: Jiri Kosina

block: Fix dev_t minor allocation lifetime

2014-09-03T21:01:02+00:00

Releases the dev_t minor when all references are closed to prevent another device from acquiring the same major/minor. Since the partition's release may be invoked from call_rcu's soft-irq context, the ext_dev_idr's mutex had to be replaced with a spinlock so as not so sleep. Signed-off-by: Keith Busch Cc: stable@kernel.org Signed-off-by: Jens Axboe

block: Convert kmalloc_node(...GFP_ZERO...) to kzalloc_node(...)

2013-09-11T19:22:03+00:00

Use the helper function instead of __GFP_ZERO. Signed-off-by: Joe Perches Signed-off-by: Jens Axboe

block: do not pass disk names as format strings

2013-07-03T23:07:25+00:00

Disk names may contain arbitrary strings, so they must not be interpreted as format strings. It seems that only md allows arbitrary strings to be used for disk names, but this could allow for a local memory corruption from uid 0 into ring 0. CVE-2013-2851 Signed-off-by: Kees Cook Cc: Jens Axboe Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

block: queue work on power efficient wq

2013-05-14T17:50:07+00:00

Block layer uses workqueues for multiple purposes. There is no real dependency of scheduling these on the cpu which scheduled them. On a idle system, it is observed that and idle cpu wakes up many times just to service this work. It would be better if we can schedule it on a cpu which the scheduler believes to be the most appropriate one. This patch replaces normal workqueues with power efficient versions. Cc: Jens Axboe Signed-off-by: Viresh Kumar Signed-off-by: Tejun Heo