kernel/linux.git/drivers/ide/ide-cd.c, branch v4.4.171

cdrom: do not call check_disk_change() inside cdrom_open()

2018-05-30T05:49:13+00:00

[ Upstream commit 2bbea6e117357d17842114c65e9a9cf2d13ae8a3 ] when mounting an ISO filesystem sometimes (very rarely) the system hangs because of a race condition between two tasks. PID: 6766 TASK: ffff88007b2a6dd0 CPU: 0 COMMAND: "mount" #0 [ffff880078447ae0] __schedule at ffffffff8168d605 #1 [ffff880078447b48] schedule_preempt_disabled at ffffffff8168ed49 #2 [ffff880078447b58] __mutex_lock_slowpath at ffffffff8168c995 #3 [ffff880078447bb8] mutex_lock at ffffffff8168bdef #4 [ffff880078447bd0] sr_block_ioctl at ffffffffa00b6818 [sr_mod] #5 [ffff880078447c10] blkdev_ioctl at ffffffff812fea50 #6 [ffff880078447c70] ioctl_by_bdev at ffffffff8123a8b3 #7 [ffff880078447c90] isofs_fill_super at ffffffffa04fb1e1 [isofs] #8 [ffff880078447da8] mount_bdev at ffffffff81202570 #9 [ffff880078447e18] isofs_mount at ffffffffa04f9828 [isofs] #10 [ffff880078447e28] mount_fs at ffffffff81202d09 #11 [ffff880078447e70] vfs_kern_mount at ffffffff8121ea8f #12 [ffff880078447ea8] do_mount at ffffffff81220fee #13 [ffff880078447f28] sys_mount at ffffffff812218d6 #14 [ffff880078447f80] system_call_fastpath at ffffffff81698c49 RIP: 00007fd9ea914e9a RSP: 00007ffd5d9bf648 RFLAGS: 00010246 RAX: 00000000000000a5 RBX: ffffffff81698c49 RCX: 0000000000000010 RDX: 00007fd9ec2bc210 RSI: 00007fd9ec2bc290 RDI: 00007fd9ec2bcf30 RBP: 0000000000000000 R8: 0000000000000000 R9: 0000000000000010 R10: 00000000c0ed0001 R11: 0000000000000206 R12: 00007fd9ec2bc040 R13: 00007fd9eb6b2380 R14: 00007fd9ec2bc210 R15: 00007fd9ec2bcf30 ORIG_RAX: 00000000000000a5 CS: 0033 SS: 002b This task was trying to mount the cdrom. It allocated and configured a super_block struct and owned the write-lock for the super_block->s_umount rwsem. While exclusively owning the s_umount lock, it called sr_block_ioctl and waited to acquire the global sr_mutex lock. PID: 6785 TASK: ffff880078720fb0 CPU: 0 COMMAND: "systemd-udevd" #0 [ffff880078417898] __schedule at ffffffff8168d605 #1 [ffff880078417900] schedule at ffffffff8168dc59 #2 [ffff880078417910] rwsem_down_read_failed at ffffffff8168f605 #3 [ffff880078417980] call_rwsem_down_read_failed at ffffffff81328838 #4 [ffff8800784179d0] down_read at ffffffff8168cde0 #5 [ffff8800784179e8] get_super at ffffffff81201cc7 #6 [ffff880078417a10] __invalidate_device at ffffffff8123a8de #7 [ffff880078417a40] flush_disk at ffffffff8123a94b #8 [ffff880078417a88] check_disk_change at ffffffff8123ab50 #9 [ffff880078417ab0] cdrom_open at ffffffffa00a29e1 [cdrom] #10 [ffff880078417b68] sr_block_open at ffffffffa00b6f9b [sr_mod] #11 [ffff880078417b98] __blkdev_get at ffffffff8123ba86 #12 [ffff880078417bf0] blkdev_get at ffffffff8123bd65 #13 [ffff880078417c78] blkdev_open at ffffffff8123bf9b #14 [ffff880078417c90] do_dentry_open at ffffffff811fc7f7 #15 [ffff880078417cd8] vfs_open at ffffffff811fc9cf #16 [ffff880078417d00] do_last at ffffffff8120d53d #17 [ffff880078417db0] path_openat at ffffffff8120e6b2 #18 [ffff880078417e48] do_filp_open at ffffffff8121082b #19 [ffff880078417f18] do_sys_open at ffffffff811fdd33 #20 [ffff880078417f70] sys_open at ffffffff811fde4e #21 [ffff880078417f80] system_call_fastpath at ffffffff81698c49 RIP: 00007f29438b0c20 RSP: 00007ffc76624b78 RFLAGS: 00010246 RAX: 0000000000000002 RBX: ffffffff81698c49 RCX: 0000000000000000 RDX: 00007f2944a5fa70 RSI: 00000000000a0800 RDI: 00007f2944a5fa70 RBP: 00007f2944a5f540 R8: 0000000000000000 R9: 0000000000000020 R10: 00007f2943614c40 R11: 0000000000000246 R12: ffffffff811fde4e R13: ffff880078417f78 R14: 000000000000000c R15: 00007f2944a4b010 ORIG_RAX: 0000000000000002 CS: 0033 SS: 002b This task tried to open the cdrom device, the sr_block_open function acquired the global sr_mutex lock. The call to check_disk_change() then saw an event flag indicating a possible media change and tried to flush any cached data for the device. As part of the flush, it tried to acquire the super_block->s_umount lock associated with the cdrom device. This was the same super_block as created and locked by the previous task. The first task acquires the s_umount lock and then the sr_mutex_lock; the second task acquires the sr_mutex_lock and then the s_umount lock. This patch fixes the issue by moving check_disk_change() out of cdrom_open() and let the caller take care of it. Signed-off-by: Maurizio Lombardi Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

mm, page_alloc: rename __GFP_WAIT to __GFP_RECLAIM

2015-11-07T01:50:42+00:00

__GFP_WAIT was used to signal that the caller was in atomic context and could not sleep. Now it is possible to distinguish between true atomic context and callers that are not willing to sleep. The latter should clear __GFP_DIRECT_RECLAIM so kswapd will still wake. As clearing __GFP_WAIT behaves differently, there is a risk that people will clear the wrong flags. This patch renames __GFP_WAIT to __GFP_RECLAIM to clearly indicate what it does -- setting it allows all reclaim activity, clearing them prevents it. [akpm@linux-foundation.org: fix build] [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Mel Gorman Acked-by: Michal Hocko Acked-by: Vlastimil Babka Acked-by: Johannes Weiner Cc: Christoph Lameter Acked-by: David Rientjes Cc: Vitaly Wool Cc: Rik van Riel Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

block: move REQ_TYPE_SENSE to the ide driver

2015-05-05T19:40:07+00:00

Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe

block: rename REQ_TYPE_SPECIAL to REQ_TYPE_DRV_PRIV

2015-05-05T19:40:03+00:00

Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe

drivers: avoid format string in dev_set_name

2013-07-03T23:07:41+00:00

Calling dev_set_name with a single paramter causes it to be handled as a format string. Many callers are passing potentially dynamic string content, so use "%s" in those cases to avoid any potential accidents, including wrappers like device_create*() and bdi_register(). Signed-off-by: Kees Cook Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

block_device_operations->release() should return void

2013-05-07T06:16:21+00:00

The value passed is 0 in all but "it can never happen" cases (and those only in a couple of drivers) *and* it would've been lost on the way out anyway, even if something tried to pass something meaningful. Just don't bother. Signed-off-by: Al Viro

procfs: new helper - PDE_DATA(inode)

2013-04-09T18:13:32+00:00

The only part of proc_dir_entry the code outside of fs/proc really cares about is PDE(inode)->data. Provide a helper for that; static inline for now, eventually will be moved to fs/proc, along with the knowledge of struct proc_dir_entry layout. Signed-off-by: Al Viro

ide-{cd,floppy,tape}: Do not include

2011-11-08T21:35:46+00:00

The top of has this comment: * Please do not include this file in generic code. There is currently * no requirement for any architecture to implement anything held * within this file. * * Thanks. --rmk Remove inclusion of , to prevent the following compile error from happening soon: | include/linux/irq.h:132: error: redefinition of ‘struct irq_data’ | include/linux/irq.h:286: error: redefinition of ‘struct irq_chip’ Signed-off-by: Geert Uytterhoeven Acked-by: Thomas Gleixner Acked-by: Borislav Petkov Cc: linux-ide@vger.kernel.org

ide-cd: signedness warning fix again

2011-06-11T22:06:48+00:00

One of the legit warnings 'make W=3 drivers/ide/ide-cd.c' generates is: drivers/ide/ide-cd.c: In function ide_cd_do_request drivers/ide/ide-cd.c:828:2: warning: conversion to int from \ unsigned int may change the sign of the result drivers/ide/ide-cd.c:833:2: warning: conversion to int from \ unsigned int may change the sign of the result nsectors is declared int, should be unsigned int. blk_rq_sectors() returns unsigned int, and ide_complete_rq expects unsigned int as well. Fixes both warnings. Signed-off-by: Connor Hansen Signed-off-by: David S. Miller

block: fix mismerge of the DISK_EVENT_MEDIA_CHANGE removal

2011-06-01T20:29:19+00:00

Jens' back-merge commit 698567f3fa79 ("Merge commit 'v2.6.39' into for-2.6.40/core") was incorrectly done, and re-introduced the DISK_EVENT_MEDIA_CHANGE lines that had been removed earlier in commits - 9fd097b14918 ("block: unexport DISK_EVENT_MEDIA_CHANGE for legacy/fringe drivers") - 7eec77a1816a ("ide: unexport DISK_EVENT_MEDIA_CHANGE for ide-gd and ide-cd") because of conflicts with the "g->flags" updates near-by by commit d4dc210f69bc ("block: don't block events on excl write for non-optical devices") As a result, we re-introduced the hanging behavior due to infinite disk media change reports. Tssk, tssk, people! Don't do back-merges at all, and *definitely* don't do them to hide merge conflicts from me - especially as I'm likely better at merging them than you are, since I do so many merges. Reported-by: Steven Rostedt Cc: Jens Axboe Signed-off-by: Linus Torvalds