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2012-01-13module_param: make bool parameters really bool (drivers & misc)Rusty Russell
module_param(bool) used to counter-intuitively take an int. In fddd5201 (mid-2009) we allowed bool or int/unsigned int using a messy trick. It's time to remove the int/unsigned int option. For this version it'll simply give a warning, but it'll break next kernel version. Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-13module_param: avoid bool abuse, add bint for special cases.Rusty Russell
For historical reasons, we allow module_param(bool) to take an int (or an unsigned int). That's going away. A few drivers really want an int: they set it to -1 and a parameter will set it to 0 or 1. This sucks: reading them from sysfs will give 'Y' for both -1 and 1, but if we change it to an int, then the users might be broken (if they did "param" instead of "param=1"). Use a new 'bint' parser for them. (ntfs has a different problem: it needs an int for debug_msgs because it's also exposed via sysctl.) Cc: Steve Glendinning <steve.glendinning@smsc.com> Cc: Jean Delvare <khali@linux-fr.org> Cc: Guenter Roeck <guenter.roeck@ericsson.com> Cc: Hoang-Nam Nguyen <hnguyen@de.ibm.com> Cc: Christoph Raisch <raisch@de.ibm.com> Cc: Roland Dreier <roland@kernel.org> Cc: Sean Hefty <sean.hefty@intel.com> Cc: Hal Rosenstock <hal.rosenstock@gmail.com> Cc: linux390@de.ibm.com Cc: Anton Altaparmakov <anton@tuxera.com> Cc: Jaroslav Kysela <perex@perex.cz> Cc: Takashi Iwai <tiwai@suse.de> Cc: lm-sensors@lm-sensors.org Cc: linux-rdma@vger.kernel.org Cc: linux-s390@vger.kernel.org Cc: linux-ntfs-dev@lists.sourceforge.net Cc: alsa-devel@alsa-project.org Acked-by: Takashi Iwai <tiwai@suse.de> (For the sound part) Acked-by: Guenter Roeck <guenter.roeck@ericsson.com> (For the hwmon driver) Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-12Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: FUSE: Notifying the kernel of deletion. fuse: support ioctl on directories fuse: Use kcalloc instead of kzalloc to allocate array fuse: llseek optimize SEEK_CUR and SEEK_SET
2012-01-10Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: autofs4: deal with autofs4_write/autofs4_write races autofs4: catatonic_mode vs. notify_daemon race autofs4: autofs4_wait() vs. autofs4_catatonic_mode() race hfsplus: creation of hidden dir on mount can fail block_dev: Suppress bdev_cache_init() kmemleak warninig fix shrink_dcache_parent() livelock coda: switch coda_cnode_make() to sane API as well, clean coda_lookup() coda: deal correctly with allocation failure from coda_cnode_makectl() securityfs: fix object creation races
2012-01-11autofs4: deal with autofs4_write/autofs4_write racesAl Viro
Just serialize the actual writing of packets into pipe on a new mutex, independent from everything else in the locking hierarchy. As soon as something has started feeding a piece of packet into the pipe to daemon, we *want* everything else about to try the same to wait until we are done. Acked-by: Ian Kent <raven@themaw.net> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-11autofs4: catatonic_mode vs. notify_daemon raceAl Viro
we need to hold ->wq_mutex while we are forming the packet to send, lest we have autofs4_catatonic_mode() setting wq->name.name to NULL just as autofs4_notify_daemon() decides to memcpy() from it... We do have check for catatonic mode immediately after that (under ->wq_mutex, as it ought to be) and packet won't be actually sent, but it'll be too late for us if we oops on that memcpy() from NULL... Fix is obvious - just extend the area covered by ->wq_mutex over that switch and check whether it's catatonic *before* doing anything else. Acked-by: Ian Kent <raven@themaw.net> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-11autofs4: autofs4_wait() vs. autofs4_catatonic_mode() raceAl Viro
We need to recheck ->catatonic after autofs4_wait() got ->wq_mutex for good, or we might end up with wq inserted into queue after autofs4_catatonic_mode() had done its thing. It will stick there forever, since there won't be anything to clear its ->name.name. A bit of a complication: validate_request() drops and regains ->wq_mutex. It actually ends up the most convenient place to stick the check into... Acked-by: Ian Kent <raven@themaw.net> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-10Merge branch 'writeback-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux * 'writeback-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux: writeback: move MIN_WRITEBACK_PAGES to fs-writeback.c writeback: balanced_rate cannot exceed write bandwidth writeback: do strict bdi dirty_exceeded writeback: avoid tiny dirty poll intervals writeback: max, min and target dirty pause time writeback: dirty ratelimit - think time compensation btrfs: fix dirtied pages accounting on sub-page writes writeback: fix dirtied pages accounting on redirty writeback: fix dirtied pages accounting on sub-page writes writeback: charge leaked page dirties to active tasks writeback: Include all dirty inodes in background writeback
2012-01-10Merge branch 'akpm' (aka "Andrew's patch-bomb")Linus Torvalds
Andrew elucidates: - First installmeant of MM. We have a HUGE number of MM patches this time. It's crazy. - MAINTAINERS updates - backlight updates - leds - checkpatch updates - misc ELF stuff - rtc updates - reiserfs - procfs - some misc other bits * akpm: (124 commits) user namespace: make signal.c respect user namespaces workqueue: make alloc_workqueue() take printf fmt and args for name procfs: add hidepid= and gid= mount options procfs: parse mount options procfs: introduce the /proc/<pid>/map_files/ directory procfs: make proc_get_link to use dentry instead of inode signal: add block_sigmask() for adding sigmask to current->blocked sparc: make SA_NOMASK a synonym of SA_NODEFER reiserfs: don't lock root inode searching reiserfs: don't lock journal_init() reiserfs: delay reiserfs lock until journal initialization reiserfs: delete comments referring to the BKL drivers/rtc/interface.c: fix alarm rollover when day or month is out-of-range drivers/rtc/rtc-twl.c: add DT support for RTC inside twl4030/twl6030 drivers/rtc/: remove redundant spi driver bus initialization drivers/rtc/rtc-jz4740.c: make jz4740_rtc_driver static drivers/rtc/rtc-mc13xxx.c: make mc13xxx_rtc_idtable static rtc: convert drivers/rtc/* to use module_platform_driver() drivers/rtc/rtc-wm831x.c: convert to devm_kzalloc() drivers/rtc/rtc-wm831x.c: remove unused period IRQ handler ...
2012-01-10procfs: add hidepid= and gid= mount optionsVasiliy Kulikov
Add support for mount options to restrict access to /proc/PID/ directories. The default backward-compatible "relaxed" behaviour is left untouched. The first mount option is called "hidepid" and its value defines how much info about processes we want to be available for non-owners: hidepid=0 (default) means the old behavior - anybody may read all world-readable /proc/PID/* files. hidepid=1 means users may not access any /proc/<pid>/ directories, but their own. Sensitive files like cmdline, sched*, status are now protected against other users. As permission checking done in proc_pid_permission() and files' permissions are left untouched, programs expecting specific files' modes are not confused. hidepid=2 means hidepid=1 plus all /proc/PID/ will be invisible to other users. It doesn't mean that it hides whether a process exists (it can be learned by other means, e.g. by kill -0 $PID), but it hides process' euid and egid. It compicates intruder's task of gathering info about running processes, whether some daemon runs with elevated privileges, whether another user runs some sensitive program, whether other users run any program at all, etc. gid=XXX defines a group that will be able to gather all processes' info (as in hidepid=0 mode). This group should be used instead of putting nonroot user in sudoers file or something. However, untrusted users (like daemons, etc.) which are not supposed to monitor the tasks in the whole system should not be added to the group. hidepid=1 or higher is designed to restrict access to procfs files, which might reveal some sensitive private information like precise keystrokes timings: http://www.openwall.com/lists/oss-security/2011/11/05/3 hidepid=1/2 doesn't break monitoring userspace tools. ps, top, pgrep, and conky gracefully handle EPERM/ENOENT and behave as if the current user is the only user running processes. pstree shows the process subtree which contains "pstree" process. Note: the patch doesn't deal with setuid/setgid issues of keeping preopened descriptors of procfs files (like https://lkml.org/lkml/2011/2/7/368). We rely on that the leaked information like the scheduling counters of setuid apps doesn't threaten anybody's privacy - only the user started the setuid program may read the counters. Signed-off-by: Vasiliy Kulikov <segoon@openwall.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Greg KH <greg@kroah.com> Cc: Theodore Tso <tytso@MIT.EDU> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: James Morris <jmorris@namei.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10procfs: parse mount optionsVasiliy Kulikov
Add support for procfs mount options. Actual mount options are coming in the next patches. Signed-off-by: Vasiliy Kulikov <segoon@openwall.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Greg KH <greg@kroah.com> Cc: Theodore Tso <tytso@MIT.EDU> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: James Morris <jmorris@namei.org> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10procfs: introduce the /proc/<pid>/map_files/ directoryPavel Emelyanov
This one behaves similarly to the /proc/<pid>/fd/ one - it contains symlinks one for each mapping with file, the name of a symlink is "vma->vm_start-vma->vm_end", the target is the file. Opening a symlink results in a file that point exactly to the same inode as them vma's one. For example the ls -l of some arbitrary /proc/<pid>/map_files/ | lr-x------ 1 root root 64 Aug 26 06:40 7f8f80403000-7f8f80404000 -> /lib64/libc-2.5.so | lr-x------ 1 root root 64 Aug 26 06:40 7f8f8061e000-7f8f80620000 -> /lib64/libselinux.so.1 | lr-x------ 1 root root 64 Aug 26 06:40 7f8f80826000-7f8f80827000 -> /lib64/libacl.so.1.1.0 | lr-x------ 1 root root 64 Aug 26 06:40 7f8f80a2f000-7f8f80a30000 -> /lib64/librt-2.5.so | lr-x------ 1 root root 64 Aug 26 06:40 7f8f80a30000-7f8f80a4c000 -> /lib64/ld-2.5.so This *helps* checkpointing process in three ways: 1. When dumping a task mappings we do know exact file that is mapped by particular region. We do this by opening /proc/$pid/map_files/$address symlink the way we do with file descriptors. 2. This also helps in determining which anonymous shared mappings are shared with each other by comparing the inodes of them. 3. When restoring a set of processes in case two of them has a mapping shared, we map the memory by the 1st one and then open its /proc/$pid/map_files/$address file and map it by the 2nd task. Using /proc/$pid/maps for this is quite inconvenient since it brings repeatable re-reading and reparsing for this text file which slows down restore procedure significantly. Also as being pointed in (3) it is a way easier to use top level shared mapping in children as /proc/$pid/map_files/$address when needed. [akpm@linux-foundation.org: coding-style fixes] [gorcunov@openvz.org: make map_files depend on CHECKPOINT_RESTORE] Signed-off-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Reviewed-by: Vasiliy Kulikov <segoon@openwall.com> Reviewed-by: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Tejun Heo <tj@kernel.org> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Pavel Machek <pavel@ucw.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10procfs: make proc_get_link to use dentry instead of inodeCyrill Gorcunov
Prepare the ground for the next "map_files" patch which needs a name of a link file to analyse. Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Tejun Heo <tj@kernel.org> Cc: Vasiliy Kulikov <segoon@openwall.com> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10reiserfs: don't lock root inode searchingFrederic Weisbecker
Nothing requires that we lock the filesystem until the root inode is provided. Also iget5_locked() triggers a warning because we are holding the filesystem lock while allocating the inode, which result in a lockdep suspicion that we have a lock inversion against the reclaim path: [ 1986.896979] ================================= [ 1986.896990] [ INFO: inconsistent lock state ] [ 1986.896997] 3.1.1-main #8 [ 1986.897001] --------------------------------- [ 1986.897007] inconsistent {RECLAIM_FS-ON-W} -> {IN-RECLAIM_FS-W} usage. [ 1986.897016] kswapd0/16 [HC0[0]:SC0[0]:HE1:SE1] takes: [ 1986.897023] (&REISERFS_SB(s)->lock){+.+.?.}, at: [<c01f8bd4>] reiserfs_write_lock+0x20/0x2a [ 1986.897044] {RECLAIM_FS-ON-W} state was registered at: [ 1986.897050] [<c014a5b9>] mark_held_locks+0xae/0xd0 [ 1986.897060] [<c014aab3>] lockdep_trace_alloc+0x7d/0x91 [ 1986.897068] [<c0190ee0>] kmem_cache_alloc+0x1a/0x93 [ 1986.897078] [<c01e7728>] reiserfs_alloc_inode+0x13/0x3d [ 1986.897088] [<c01a5b06>] alloc_inode+0x14/0x5f [ 1986.897097] [<c01a5cb9>] iget5_locked+0x62/0x13a [ 1986.897106] [<c01e99e0>] reiserfs_fill_super+0x410/0x8b9 [ 1986.897114] [<c01953da>] mount_bdev+0x10b/0x159 [ 1986.897123] [<c01e764d>] get_super_block+0x10/0x12 [ 1986.897131] [<c0195b38>] mount_fs+0x59/0x12d [ 1986.897138] [<c01a80d1>] vfs_kern_mount+0x45/0x7a [ 1986.897147] [<c01a83e3>] do_kern_mount+0x2f/0xb0 [ 1986.897155] [<c01a987a>] do_mount+0x5c2/0x612 [ 1986.897163] [<c01a9a72>] sys_mount+0x61/0x8f [ 1986.897170] [<c044060c>] sysenter_do_call+0x12/0x32 [ 1986.897181] irq event stamp: 7509691 [ 1986.897186] hardirqs last enabled at (7509691): [<c0190f34>] kmem_cache_alloc+0x6e/0x93 [ 1986.897197] hardirqs last disabled at (7509690): [<c0190eea>] kmem_cache_alloc+0x24/0x93 [ 1986.897209] softirqs last enabled at (7508896): [<c01294bd>] __do_softirq+0xee/0xfd [ 1986.897222] softirqs last disabled at (7508859): [<c01030ed>] do_softirq+0x50/0x9d [ 1986.897234] [ 1986.897235] other info that might help us debug this: [ 1986.897242] Possible unsafe locking scenario: [ 1986.897244] [ 1986.897250] CPU0 [ 1986.897254] ---- [ 1986.897257] lock(&REISERFS_SB(s)->lock); [ 1986.897265] <Interrupt> [ 1986.897269] lock(&REISERFS_SB(s)->lock); [ 1986.897276] [ 1986.897277] *** DEADLOCK *** [ 1986.897278] [ 1986.897286] no locks held by kswapd0/16. [ 1986.897291] [ 1986.897292] stack backtrace: [ 1986.897299] Pid: 16, comm: kswapd0 Not tainted 3.1.1-main #8 [ 1986.897306] Call Trace: [ 1986.897314] [<c0439e76>] ? printk+0xf/0x11 [ 1986.897324] [<c01482d1>] print_usage_bug+0x20e/0x21a [ 1986.897332] [<c01479b8>] ? print_irq_inversion_bug+0x172/0x172 [ 1986.897341] [<c014855c>] mark_lock+0x27f/0x483 [ 1986.897349] [<c0148d88>] __lock_acquire+0x628/0x1472 [ 1986.897358] [<c0149fae>] lock_acquire+0x47/0x5e [ 1986.897366] [<c01f8bd4>] ? reiserfs_write_lock+0x20/0x2a [ 1986.897384] [<c01f8bd4>] ? reiserfs_write_lock+0x20/0x2a [ 1986.897397] [<c043b5ef>] mutex_lock_nested+0x35/0x26f [ 1986.897409] [<c01f8bd4>] ? reiserfs_write_lock+0x20/0x2a [ 1986.897421] [<c01f8bd4>] reiserfs_write_lock+0x20/0x2a [ 1986.897433] [<c01e2edd>] map_block_for_writepage+0xc9/0x590 [ 1986.897448] [<c01b1706>] ? create_empty_buffers+0x33/0x8f [ 1986.897461] [<c0121124>] ? get_parent_ip+0xb/0x31 [ 1986.897472] [<c043ef7f>] ? sub_preempt_count+0x81/0x8e [ 1986.897485] [<c043cae0>] ? _raw_spin_unlock+0x27/0x3d [ 1986.897496] [<c0121124>] ? get_parent_ip+0xb/0x31 [ 1986.897508] [<c01e355d>] reiserfs_writepage+0x1b9/0x3e7 [ 1986.897521] [<c0173b40>] ? clear_page_dirty_for_io+0xcb/0xde [ 1986.897533] [<c014a6e3>] ? trace_hardirqs_on_caller+0x108/0x138 [ 1986.897546] [<c014a71e>] ? trace_hardirqs_on+0xb/0xd [ 1986.897559] [<c0177b38>] shrink_page_list+0x34f/0x5e2 [ 1986.897572] [<c01780a7>] shrink_inactive_list+0x172/0x22c [ 1986.897585] [<c0178464>] shrink_zone+0x303/0x3b1 [ 1986.897597] [<c043cae0>] ? _raw_spin_unlock+0x27/0x3d [ 1986.897611] [<c01788c9>] kswapd+0x3b7/0x5f2 The deadlock shouldn't happen since we are doing that allocation in the mount path, the filesystem is not available for any reclaim. Still the warning is annoying. To solve this, acquire the lock later only where we need it, right before calling reiserfs_read_locked_inode() that wants to lock to walk the tree. Reported-by: Knut Petersen <Knut_Petersen@t-online.de> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Cc: Jeff Mahoney <jeffm@suse.com> Cc: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10reiserfs: don't lock journal_init()Frederic Weisbecker
journal_init() doesn't need the lock since no operation on the filesystem is involved there. journal_read() and get_list_bitmap() have yet to be reviewed carefully though before removing the lock there. Just keep the it around these two calls for safety. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Cc: Jeff Mahoney <jeffm@suse.com> Cc: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10reiserfs: delay reiserfs lock until journal initializationFrederic Weisbecker
In the mount path, transactions that are made before journal initialization don't involve the filesystem. We can delay the reiserfs lock until we play with the journal. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Cc: Jeff Mahoney <jeffm@suse.com> Cc: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10reiserfs: delete comments referring to the BKLDavidlohr Bueso
Signed-off-by: Davidlohr Bueso <dave@gnu.org> Cc: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10fs: binfmt_elf: create Kconfig variable for PIE randomizationDavid Daney
Randomization of PIE load address is hard coded in binfmt_elf.c for X86 and ARM. Create a new Kconfig variable (CONFIG_ARCH_BINFMT_ELF_RANDOMIZE_PIE) for this and use it instead. Thus architecture specific policy is pushed out of the generic binfmt_elf.c and into the architecture Kconfig files. X86 and ARM Kconfigs are modified to select the new variable so there is no change in behavior. A follow on patch will select it for MIPS too. Signed-off-by: David Daney <david.daney@cavium.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Acked-by: H. Peter Anvin <hpa@zytor.com> Cc: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10tracepoint: add tracepoints for debugging oom_score_adjKAMEZAWA Hiroyuki
oom_score_adj is used for guarding processes from OOM-Killer. One of problem is that it's inherited at fork(). When a daemon set oom_score_adj and make children, it's hard to know where the value is set. This patch adds some tracepoints useful for debugging. This patch adds 3 trace points. - creating new task - renaming a task (exec) - set oom_score_adj To debug, users need to enable some trace pointer. Maybe filtering is useful as # EVENT=/sys/kernel/debug/tracing/events/task/ # echo "oom_score_adj != 0" > $EVENT/task_newtask/filter # echo "oom_score_adj != 0" > $EVENT/task_rename/filter # echo 1 > $EVENT/enable # EVENT=/sys/kernel/debug/tracing/events/oom/ # echo 1 > $EVENT/enable output will be like this. # grep oom /sys/kernel/debug/tracing/trace bash-7699 [007] d..3 5140.744510: oom_score_adj_update: pid=7699 comm=bash oom_score_adj=-1000 bash-7699 [007] ...1 5151.818022: task_newtask: pid=7729 comm=bash clone_flags=1200011 oom_score_adj=-1000 ls-7729 [003] ...2 5151.818504: task_rename: pid=7729 oldcomm=bash newcomm=ls oom_score_adj=-1000 bash-7699 [002] ...1 5175.701468: task_newtask: pid=7730 comm=bash clone_flags=1200011 oom_score_adj=-1000 grep-7730 [007] ...2 5175.701993: task_rename: pid=7730 oldcomm=bash newcomm=grep oom_score_adj=-1000 Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10btrfs: pass __GFP_WRITE for buffered write page allocationsJohannes Weiner
Tell the page allocator that pages allocated for a buffered write are expected to become dirty soon. Signed-off-by: Johannes Weiner <jweiner@redhat.com> Reviewed-by: Rik van Riel <riel@redhat.com> Acked-by: Mel Gorman <mgorman@suse.de> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Jan Kara <jack@suse.cz> Cc: Shaohua Li <shaohua.li@intel.com> Cc: Chris Mason <chris.mason@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10mm: account reaped page cache on inode cache pruningKonstantin Khlebnikov
Inode cache pruning indirectly reclaims page-cache by invalidating mapping pages. Let's account them into reclaim-state to notice this progress in memory reclaimer. Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Cc: Dave Chinner <david@fromorbit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10Merge tag 'ext4_for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Ext4 commits for 3.3 merge window * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (32 commits) ext4: fix undefined behavior in ext4_fill_flex_info() ext4: make more symbols static ext4: make local symbol ext4_initxattrs static jbd2: fix hung processes in jbd2_journal_lock_updates() ext4: reserve new feature flag codepoints ext4: Report max_batch_time option correctly ext4: add missing ext4_resize_end on error paths ext4: let ext4_group_add() use common code ext4: let ext4_group_extend() use common code ext4: add new online resize interface ext4: add a new function which adds a flex group to a fs ext4: add a new function which allocates bitmaps and inode tables ext4: pass verify_reserved_gdb() the number of group decriptors ext4: add a function which updates the super block during online resizing ext4: add a function which sets up a block group descriptors of a flex bg ext4: add a function which sets up group blocks of a flex bg ext4: add a structure which will be used by 64bit-resize interface ext4: add a function which adds a new group descriptors to a fs ext4: add a function which extends a group without checking parameters ext4: use proper little-endian bitops ...
2012-01-10Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs: fs/9p: iattr_valid flags are kernel internal flags map them to 9p values. fs/9p: We should not allocate a new inode when creating hardlines. fs/9p: v9fs_stat2inode should update suid/sgid bits. 9p: Reduce object size with CONFIG_NET_9P_DEBUG fs/9p: check schedule_timeout_interruptible return value Fix up trivial conflicts in fs/9p/{vfs_inode.c,vfs_inode_dotl.c} due to debug messages having changed to use p9_debug() on one hand, and the changes for umode_t on the other.
2012-01-10Merge branch 'nfs-for-3.3' of git://git.linux-nfs.org/projects/trondmy/linux-nfsLinus Torvalds
* 'nfs-for-3.3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: NFSv4: Change the default setting of the nfs4_disable_idmapping parameter NFSv4: Save the owner/group name string when doing open NFS: Remove pNFS bloat from the generic write path pnfs-obj: Must return layout on IO error pnfs-obj: pNFS errors are communicated on iodata->pnfs_error NFS: Cache state owners after files are closed NFS: Clean up nfs4_find_state_owners_locked() NFSv4: include bitmap in nfsv4 get acl data nfs: fix a minor do_div portability issue NFSv4.1: cleanup comment and debug printk NFSv4.1: change nfs4_free_slot parameters for dynamic slots NFSv4.1: cleanup init and reset of session slot tables NFSv4.1: fix backchannel slotid off-by-one bug nfs: fix regression in handling of context= option in NFSv4 NFS - fix recent breakage to NFS error handling. NFS: Retry mounting NFSROOT SUNRPC: Clean up the RPCSEC_GSS service ticket requests
2012-01-10Merge branch 'linux-next' of git://git.infradead.org/ubifs-2.6Linus Torvalds
* 'linux-next' of git://git.infradead.org/ubifs-2.6: UBI: fix use-after-free on error path UBI: fix missing scrub when there is a bit-flip UBIFS: Use kmemdup rather than duplicating its implementation
2012-01-10Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm: dlm: add recovery callbacks dlm: add node slots and generation dlm: move recovery barrier calls dlm: convert rsb list to rb_tree
2012-01-10hfsplus: creation of hidden dir on mount can failAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-10Merge tag 'for-linus-3.3' of git://git.infradead.org/mtd-2.6Linus Torvalds
MTD pull for 3.3 * tag 'for-linus-3.3' of git://git.infradead.org/mtd-2.6: (113 commits) mtd: Fix dependency for MTD_DOC200x mtd: do not use mtd->block_markbad directly logfs: do not use 'mtd->block_isbad' directly mtd: introduce mtd_can_have_bb helper mtd: do not use mtd->suspend and mtd->resume directly mtd: do not use mtd->lock, unlock and is_locked directly mtd: do not use mtd->sync directly mtd: harmonize mtd_writev usage mtd: do not use mtd->lock_user_prot_reg directly mtd: mtd->write_user_prot_reg directly mtd: do not use mtd->read_*_prot_reg directly mtd: do not use mtd->get_*_prot_info directly mtd: do not use mtd->read_oob directly mtd: mtdoops: do not use mtd->panic_write directly romfs: do not use mtd->get_unmapped_area directly mtd: do not use mtd->get_unmapped_area directly mtd: do use mtd->point directly mtd: introduce mtd_has_oob helper mtd: mtdcore: export symbols cleanup mtd: clean-up the default_mtd_writev function ... Fix up trivial edit/remove conflict in drivers/staging/spectra/lld_mtd.c
2012-01-10block_dev: Suppress bdev_cache_init() kmemleak warninigSergey Senozhatsky
Kmemleak reports the following warning in bdev_cache_init() [ 0.003738] kmemleak: Object 0xffff880153035200 (size 256): [ 0.003823] kmemleak: comm "swapper/0", pid 0, jiffies 4294667299 [ 0.003909] kmemleak: min_count = 1 [ 0.003988] kmemleak: count = 0 [ 0.004066] kmemleak: flags = 0x1 [ 0.004144] kmemleak: checksum = 0 [ 0.004224] kmemleak: backtrace: [ 0.004303] [<ffffffff814755ac>] kmemleak_alloc+0x21/0x3e [ 0.004446] [<ffffffff811100ba>] kmem_cache_alloc+0xca/0x1dc [ 0.004592] [<ffffffff811371b1>] alloc_vfsmnt+0x1f/0x198 [ 0.004736] [<ffffffff811375c5>] vfs_kern_mount+0x36/0xd2 [ 0.004879] [<ffffffff8113929a>] kern_mount_data+0x18/0x32 [ 0.005025] [<ffffffff81ab9075>] bdev_cache_init+0x51/0x81 [ 0.005169] [<ffffffff81ab8abf>] vfs_caches_init+0x101/0x10d [ 0.005313] [<ffffffff81a9bae3>] start_kernel+0x344/0x383 [ 0.005456] [<ffffffff81a9b2a7>] x86_64_start_reservations+0xae/0xb2 [ 0.005602] [<ffffffff81a9b3ad>] x86_64_start_kernel+0x102/0x111 [ 0.005747] [<ffffffffffffffff>] 0xffffffffffffffff [ 0.008653] kmemleak: Trying to color unknown object at 0xffff880153035220 as Grey [ 0.008754] Pid: 0, comm: swapper/0 Not tainted 3.3.0-rc0-dbg-04200-g8180888-dirty #888 [ 0.008856] Call Trace: [ 0.008934] [<ffffffff81118704>] ? find_and_get_object+0x44/0x118 [ 0.009023] [<ffffffff81118fe6>] paint_ptr+0x57/0x8f [ 0.009109] [<ffffffff81475935>] kmemleak_not_leak+0x23/0x42 [ 0.009195] [<ffffffff81ab9096>] bdev_cache_init+0x72/0x81 [ 0.009282] [<ffffffff81ab8abf>] vfs_caches_init+0x101/0x10d [ 0.009368] [<ffffffff81a9bae3>] start_kernel+0x344/0x383 [ 0.009466] [<ffffffff81a9b2a7>] x86_64_start_reservations+0xae/0xb2 [ 0.009555] [<ffffffff81a9b140>] ? early_idt_handlers+0x140/0x140 [ 0.009643] [<ffffffff81a9b3ad>] x86_64_start_kernel+0x102/0x111 due to attempt to mark pointer to `struct vfsmount' as a gray object, which is embedded into `struct mount' returned from alloc_vfsmnt(). Make `bd_mnt' static, avoiding need to tell kmemleak to mark it gray, as suggested by Al Viro. Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-10fix shrink_dcache_parent() livelockMiklos Szeredi
Two (or more) concurrent calls of shrink_dcache_parent() on the same dentry may cause shrink_dcache_parent() to loop forever. Here's what appears to happen: 1 - CPU0: select_parent(P) finds C and puts it on dispose list, returns 1 2 - CPU1: select_parent(P) locks P->d_lock 3 - CPU0: shrink_dentry_list() locks C->d_lock dentry_kill(C) tries to lock P->d_lock but fails, unlocks C->d_lock 4 - CPU1: select_parent(P) locks C->d_lock, moves C from dispose list being processed on CPU0 to the new dispose list, returns 1 5 - CPU0: shrink_dentry_list() finds dispose list empty, returns 6 - Goto 2 with CPU0 and CPU1 switched Basically select_parent() steals the dentry from shrink_dentry_list() and thinks it found a new one, causing shrink_dentry_list() to think it's making progress and loop over and over. One way to trigger this is to make udev calls stat() on the sysfs file while it is going away. Having a file in /lib/udev/rules.d/ with only this one rule seems to the trick: ATTR{vendor}=="0x8086", ATTR{device}=="0x10ca", ENV{PCI_SLOT_NAME}="%k", ENV{MATCHADDR}="$attr{address}", RUN+="/bin/true" Then execute the following loop: while true; do echo -bond0 > /sys/class/net/bonding_masters echo +bond0 > /sys/class/net/bonding_masters echo -bond1 > /sys/class/net/bonding_masters echo +bond1 > /sys/class/net/bonding_masters done One fix would be to check all callers and prevent concurrent calls to shrink_dcache_parent(). But I think a better solution is to stop the stealing behavior. This patch adds a new dentry flag that is set when the dentry is added to the dispose list. The flag is cleared in dentry_lru_del() in case the dentry gets a new reference just before being pruned. If the dentry has this flag, select_parent() will skip it and let shrink_dentry_list() retry pruning it. With select_parent() skipping those dentries there will not be the appearance of progress (new dentries found) when there is none, hence shrink_dcache_parent() will not loop forever. Set the flag is also set in prune_dcache_sb() for consistency as suggested by Linus. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> CC: stable@vger.kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-10Merge branch 'for_linus' into for_linus_mergedTheodore Ts'o
Conflicts: fs/ext4/ioctl.c
2012-01-10ext4: fix undefined behavior in ext4_fill_flex_info()Xi Wang
Commit 503358ae01b70ce6909d19dd01287093f6b6271c ("ext4: avoid divide by zero when trying to mount a corrupted file system") fixes CVE-2009-4307 by performing a sanity check on s_log_groups_per_flex, since it can be set to a bogus value by an attacker. sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex; groups_per_flex = 1 << sbi->s_log_groups_per_flex; if (groups_per_flex < 2) { ... } This patch fixes two potential issues in the previous commit. 1) The sanity check might only work on architectures like PowerPC. On x86, 5 bits are used for the shifting amount. That means, given a large s_log_groups_per_flex value like 36, groups_per_flex = 1 << 36 is essentially 1 << 4 = 16, rather than 0. This will bypass the check, leaving s_log_groups_per_flex and groups_per_flex inconsistent. 2) The sanity check relies on undefined behavior, i.e., oversized shift. A standard-confirming C compiler could rewrite the check in unexpected ways. Consider the following equivalent form, assuming groups_per_flex is unsigned for simplicity. groups_per_flex = 1 << sbi->s_log_groups_per_flex; if (groups_per_flex == 0 || groups_per_flex == 1) { We compile the code snippet using Clang 3.0 and GCC 4.6. Clang will completely optimize away the check groups_per_flex == 0, leaving the patched code as vulnerable as the original. GCC keeps the check, but there is no guarantee that future versions will do the same. Signed-off-by: Xi Wang <xi.wang@gmail.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: stable@vger.kernel.org
2012-01-10coda: switch coda_cnode_make() to sane API as well, clean coda_lookup()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-10coda: deal correctly with allocation failure from coda_cnode_makectl()Al Viro
lookup should fail with ENOMEM, not silently make dentry negative. Switched to saner calling conventions, while we are at it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-09Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: vfs: new helper - d_make_root() dcache: use a dispose list in select_parent ceph: d_alloc_root() may fail ext4: fix failure exits isofs: inode leak on mount failure
2012-01-09vfs: new helper - d_make_root()Al Viro
d_alloc_root() with iput() in case of allocation failure... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-09dcache: use a dispose list in select_parentDave Chinner
select_parent currently abuses the dentry cache LRU to provide cleanup features for child dentries that need to be freed. It moves them to the tail of the LRU, then tells shrink_dcache_parent() to calls __shrink_dcache_sb to unconditionally move them to a dispose list (as DCACHE_REFERENCED is ignored). __shrink_dcache_sb() has to relock the dentries to move them off the LRU onto the dispose list, but otherwise does not touch the dentries that select_parent() moved to the tail of the LRU. It then passses the dispose list to shrink_dentry_list() which tries to free the dentries. IOWs, the use of __shrink_dcache_sb() is superfluous - we can build exactly the same list of dentries for disposal directly in select_parent() and call shrink_dentry_list() instead of calling __shrink_dcache_sb() to do that. This means that we avoid long holds on the lru lock walking the LRU moving dentries to the dispose list We also avoid the need to relock each dentry just to move it off the LRU, reducing the numebr of times we lock each dentry to dispose of them in shrink_dcache_parent() from 3 to 2 times. Further, we remove one of the two callers of __shrink_dcache_sb(). This also means that __shrink_dcache_sb can be moved into back into prune_dcache_sb() and we no longer have to handle referenced dentries conditionally, simplifying the code. Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-09ceph: d_alloc_root() may failAl Viro
... and ceph_init_dentry(NULL) will oops Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-09ext4: fix failure exitsAl Viro
a) leaking root dentry is bad b) in case of failed ext4_mb_init() we don't want to do ext4_mb_release() c) OTOH, in the same case we *do* want ext4_ext_release() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-09Merge branch 'for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs * 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: ext2/3/4: delete unneeded includes of module.h ext{3,4}: Fix potential race when setversion ioctl updates inode udf: Mark LVID buffer as uptodate before marking it dirty ext3: Don't warn from writepage when readonly inode is spotted after error jbd: Remove j_barrier mutex reiserfs: Force inode evictions before umount to avoid crash reiserfs: Fix quota mount option parsing udf: Treat symlink component of type 2 as / udf: Fix deadlock when converting file from in-ICB one to normal one udf: Cleanup calling convention of inode_getblk() ext2: Fix error handling on inode bitmap corruption ext3: Fix error handling on inode bitmap corruption ext3: replace ll_rw_block with other functions ext3: NULL dereference in ext3_evict_inode() jbd: clear revoked flag on buffers before a new transaction started ext3: call ext3_mark_recovery_complete() when recovery is really needed
2012-01-09Merge branch 'for-linus' of git://git.open-osd.org/linux-open-osdLinus Torvalds
* 'for-linus' of git://git.open-osd.org/linux-open-osd: ore: Must support none-PAGE-aligned IO ore: fix BUG_ON, too few sgs when reading ore: Fix crash in case of an IO error. ore: FIX breakage when MISC_FILESYSTEMS is not set
2012-01-09Merge branch 'for-linus' of git://oss.sgi.com/xfs/xfsLinus Torvalds
* 'for-linus' of git://oss.sgi.com/xfs/xfs: xfs: fix endian conversion issue in discard code
2012-01-09Merge branch 'usb-next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb * 'usb-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (232 commits) USB: Add USB-ID for Multiplex RC serial adapter to cp210x.c xhci: Clean up 32-bit build warnings. USB: update documentation for usbmon usb: usb-storage doesn't support dynamic id currently, the patch disables the feature to fix an oops drivers/usb/class/cdc-acm.c: clear dangling pointer drivers/usb/dwc3/dwc3-pci.c: introduce missing kfree drivers/usb/host/isp1760-if.c: introduce missing kfree usb: option: add ZD Incorporated HSPA modem usb: ch9: fix up MaxStreams helper USB: usb-skeleton.c: cleanup open_count USB: usb-skeleton.c: fix open/disconnect race xhci: Properly handle COMP_2ND_BW_ERR USB: remove dead code from suspend/resume path USB: add quirk for another camera drivers: usb: wusbcore: Fix dependency for USB_WUSB xhci: Better debugging for critical host errors. xhci: Be less verbose during URB cancellation. xhci: Remove debugging about ring structure allocation. xhci: Remove debugging about toggling cycle bits. xhci: Remove debugging for individual transfers. ...
2012-01-09Merge branch 'char-misc-next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc * 'char-misc-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: isl29020: Remove a redundant semi-colon from return statement BMP085: Remove redundant semi-colon from return statement drivers:misc: ti-st: DEBUG uart, baud rate mods drivers:misc: ti-st: flush UART upon fw failure drivers:misc: ti-st: protect registrations char_dev.c: fix up some whitespace errors s390: tape_class.h: remove kobj_map.h inclusion misc: ad525x_dpot: Add support for SPI module device table matching
2012-01-09NFSv4: Change the default setting of the nfs4_disable_idmapping parameterTrond Myklebust
Now that the use of numeric uids/gids is officially sanctioned in RFC3530bis, it is time to change the default here to 'enabled'. By doing so, we ensure that NFSv4 copies the behaviour of NFSv3 when we're using the default AUTH_SYS authentication (i.e. when the client uses the numeric uids/gids as authentication tokens), so that when new files are created, they will appear to have the correct user/group. It also fixes a number of backward compatibility issues when migrating from NFSv3 to NFSv4 on a platform where the server uses different uid/gid mappings than the client. Note also that this setting has been successfully tested against servers that do not support numeric uids/gids at several Connectathon/Bakeathon events at this point, and the fall back to using string names/groups has been shown to work well in all those test cases. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-09mtd: do not use mtd->block_markbad directlyArtem Bityutskiy
Instead, use the new 'mtd_can_have_bb()', or just rely on 'mtd_block_markbad()' return code, which will be -EOPNOTSUPP if bad blocks are not supported. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09logfs: do not use 'mtd->block_isbad' directlyArtem Bityutskiy
Instead, use the new 'mtd_can_have_bb()' helper. Cc: Jörn Engel <joern@logfs.org> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09mtd: do not use mtd->sync directlyArtem Bityutskiy
This patch teaches 'mtd_sync()' to do nothing when the MTD driver does not have the '->sync()' method, which allows us to remove all direct 'mtd->sync' accesses. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09mtd: harmonize mtd_writev usageArtem Bityutskiy
This patch makes the 'mtd_writev()' function more usable and logical. We first teach it to fall-back to the 'default_mtd_writev()' function if the MTD driver does not define its own '->writev()' method. Then we make block2mtd and JFFS2 just 'mtd_writev()' instead of 'default_mtd_writev()' function. This means we can now stop exporting 'default_mtd_writev()' and instead, export 'mtd_writev()'. This is much cleaner and more logical, as well as allows us to get read of another direct 'mtd->writev' access in JFFS2. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09romfs: do not use mtd->get_unmapped_area directlyArtem Bityutskiy
Remove direct usage of mtd->get_unmapped_area. Instead, just call 'mtd_get_unmapped_area()' which will return -EOPNOTSUPP if the function is not implemented, and then test for this code. We also translate -EOPNOTSUPP to -ENOSYS because this return code is probably part of the kernel ABI which we do not want to break. Cc: linux-fsdevel@vger.kernel.org Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>