Minchan Kim [Tue, 31 Jul 2012 23:42:59 +0000 (16:42 -0700)]
mm: do not use page_count() without a page pin
d179e84ba ("mm: vmscan: do not use page_count without a page pin") fixed
this problem in vmscan.c but same problem is in __count_immobile_pages().
I copy and paste d179e84ba's contents for description.
"It is unsafe to run page_count during the physical pfn scan because
compound_head could trip on a dangling pointer when reading
page->first_page if the compound page is being freed by another CPU."
Signed-off-by: Minchan Kim <minchan@kernel.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@suse.cz> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Wanpeng Li <liwp.linux@gmail.com> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Rientjes [Tue, 31 Jul 2012 23:42:56 +0000 (16:42 -0700)]
mm, oom: replace some information in tasklist dump
The number of ptes and swap entries are used in the oom killer's badness
heuristic, so they should be shown in the tasklist dump.
This patch adds those fields and replaces cpu and oom_adj values that are
currently emitted. Cpu isn't interesting and oom_adj is deprecated and
will be removed later this year, the same information is already displayed
as oom_score_adj which is used internally.
At the same time, make the documentation a little more clear to state this
information is helpful to determine why the oom killer chose the task it
did to kill.
Signed-off-by: David Rientjes <rientjes@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Rientjes [Tue, 31 Jul 2012 23:42:55 +0000 (16:42 -0700)]
mm, oom: fix potential killing of thread that is disabled from oom killing
/proc/sys/vm/oom_kill_allocating_task will immediately kill current when
the oom killer is called to avoid a potentially expensive tasklist scan
for large systems.
Currently, however, it is not checking current's oom_score_adj value which
may be OOM_SCORE_ADJ_MIN, meaning that it has been disabled from oom
killing.
This patch avoids killing current in such a condition and simply falls
back to the tasklist scan since memory still needs to be freed.
Signed-off-by: David Rientjes <rientjes@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm: clear pages_scanned only if draining a pcp adds pages to the buddy allocator again
commit 2ff754fa8f ("mm: clear pages_scanned only if draining a pcp adds
pages to the buddy allocator again") fixed one free_pcppages_bulk()
misuse. But two another miuse still exist.
This patch fixes it.
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Mel Gorman <mel@csn.ul.ie> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Minchan Kim <minchan@kernel.org> Cc: Wu Fengguang <fengguang.wu@intel.com> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm, fadvise: don't return -EINVAL when filesystem cannot implement fadvise()
Eric Wong reported his test suite failex when /tmp is tmpfs.
https://lkml.org/lkml/2012/2/24/479
Currentlt the input check of POSIX_FADV_WILLNEED has two problems.
- requires a_ops->readpage. But in fact, force_page_cache_readahead()
requires that the target filesystem has either ->readpage or ->readpages.
- returns -EINVAL when the filesystem doesn't have ->readpage. But
posix says that fadvise is merely a hint. Thus fadvise() should return
0 if filesystem has no means of implementing fadvise(). The userland
application should not know nor care whcih type of filesystem backs the
TMPDIR directory, as Eric pointed out. There is nothing which userspace
can do to solve this error.
So change the return value to 0 when filesytem doesn't support readahead.
[akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Hugh Dickins <hughd@google.com> Cc: Hillf Danton <dhillf@gmail.com> Signed-off-by: Eric Wong <normalperson@yhbt.net> Tested-by: Eric Wong <normalperson@yhbt.net> Reviewed-by: Wanlong Gao <gaowanlong@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
memcg: make mem_cgroup_force_empty_list() return bool
mem_cgroup_force_empty_list() just returns 0 or -EBUSY and -EBUSY
indicates 'you need to retry'. Make mem_cgroup_force_empty_list() return
a bool to simplify the logic.
[akpm@linux-foundation.org: rework mem_cgroup_force_empty_list()'s comment] Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
memcg: clean up force_empty_list() return value check
After bf544fdc241da8 "memcg: move charges to root cgroup if
use_hierarchy=0 in mem_cgroup_move_hugetlb_parent()"
mem_cgroup_move_parent() returns only -EBUSY or -EINVAL. So we can remove
the -ENOMEM and -EINTR checks.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by: Michal Hocko <mhocko@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
memcg: remove check for signal_pending() during rmdir()
After bf544fdc241da8 "memcg: move charges to root cgroup if
use_hierarchy=0 in mem_cgroup_move_hugetlb_parent()", no memory reclaim
will occur when removing a memory cgroup. If -EINTR is returned here,
cgroup will show a warning.
We don't need to handle any user interruption signal. Remove this.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Rientjes [Tue, 31 Jul 2012 23:42:37 +0000 (16:42 -0700)]
mm, oom: do not schedule if current has been killed
The oom killer currently schedules away from current in an uninterruptible
sleep if it does not have access to memory reserves. It's possible that
current was killed because it shares memory with the oom killed thread or
because it was killed by the user in the interim, however.
This patch only schedules away from current if it does not have a pending
kill, i.e. if it does not share memory with the oom killed thread. It's
possible that it will immediately retry its memory allocation and fail,
but it will immediately be given access to memory reserves if it calls the
oom killer again.
This prevents the delay of memory freeing when threads that share memory
with the oom killed thread get unnecessarily scheduled.
hugetlb/cgroup: remove exclude and wakeup rmdir calls from migrate
We already hold the hugetlb_lock. That should prevent a parallel cgroup
rmdir from touching page's hugetlb cgroup. So remove the exclude and
wakeup calls.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Reviewed-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
hugetlb/cgroup: assign the page hugetlb cgroup when we move the page to active list.
A page's hugetlb cgroup assignment and movement to the active list should
occur with hugetlb_lock held. Otherwise when we remove the hugetlb cgroup
we will iterate the active list and find pages with NULL hugetlb cgroup
values.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Reviewed-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When we fail to allocate pages from the reserve pool, hugetlb tries to
allocate huge pages using alloc_buddy_huge_page. Add these to the active
list. We also need to add the huge page we allocate when we soft offline
the oldpage to active list.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Reviewed-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
hugetlb/cgroup: migrate hugetlb cgroup info from oldpage to new page during migration
With HugeTLB pages, hugetlb cgroup is uncharged in compound page
destructor. Since we are holding a hugepage reference, we can be sure
that old page won't get uncharged till the last put_page().
hugetlb/cgroup: add charge/uncharge routines for hugetlb cgroup
Add the charge and uncharge routines for hugetlb cgroup. We do cgroup
charging in page alloc and uncharge in compound page destructor.
Assigning page's hugetlb cgroup is protected by hugetlb_lock.
[liwp@linux.vnet.ibm.com: add huge_page_order check to avoid incorrect uncharge] Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: David Rientjes <rientjes@google.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Wanpeng Li <liwp.linux@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
hugetlb/cgroup: add the cgroup pointer to page lru
Add the hugetlb cgroup pointer to 3rd page lru.next. This limit the usage
to hugetlb cgroup to only hugepages with 3 or more normal pages. I guess
that is an acceptable limitation.
Implement a new controller that allows us to control HugeTLB allocations.
The extension allows to limit the HugeTLB usage per control group and
enforces the controller limit during page fault. Since HugeTLB doesn't
support page reclaim, enforcing the limit at page fault time implies that,
the application will get SIGBUS signal if it tries to access HugeTLB pages
beyond its limit. This requires the application to know beforehand how
much HugeTLB pages it would require for its use.
The charge/uncharge calls will be added to HugeTLB code in later patch.
Support for cgroup removal will be added in later patches.
hugetlb: add a list for tracking in-use HugeTLB pages
hugepage_activelist will be used to track currently used HugeTLB pages.
We need to find the in-use HugeTLB pages to support HugeTLB cgroup removal.
On cgroup removal we update the page's HugeTLB cgroup to point to parent
cgroup.
Since we migrate only one hugepage, don't use linked list for passing the
page around. Directly pass the page that need to be migrated as argument.
This also removes the usage of page->lru in the migrate path.
The current use of VM_FAULT_* codes with ERR_PTR requires us to ensure
VM_FAULT_* values will not exceed MAX_ERRNO value. Decouple the
VM_FAULT_* values from MAX_ERRNO.
This patchset implements a cgroup resource controller for HugeTLB pages.
The controller allows to limit the HugeTLB usage per control group and
enforces the controller limit during page fault. Since HugeTLB doesn't
support page reclaim, enforcing the limit at page fault time implies that,
the application will get SIGBUS signal if it tries to access HugeTLB pages
beyond its limit. This requires the application to know beforehand how
much HugeTLB pages it would require for its use.
The goal is to control how many HugeTLB pages a group of task can
allocate. It can be looked at as an extension of the existing quota
interface which limits the number of HugeTLB pages per hugetlbfs
superblock. HPC job scheduler requires jobs to specify their resource
requirements in the job file. Once their requirements can be met, job
schedulers like (SLURM) will schedule the job. We need to make sure that
the jobs won't consume more resources than requested. If they do we
should either error out or kill the application.
This patch:
Rename max_hstate to hugetlb_max_hstate. We will be using this from other
subsystems like hugetlb controller in later patches.
Wanpeng Li [Tue, 31 Jul 2012 23:41:52 +0000 (16:41 -0700)]
mm: prepare for removal of obsolete /proc/sys/vm/nr_pdflush_threads
Since per-BDI flusher threads were introduced in 2.6, the pdflush
mechanism is not used any more. But the old interface exported through
/proc/sys/vm/nr_pdflush_threads still exists and is obviously useless.
For back-compatibility, printk warning information and return 2 to notify
the users that the interface is removed.
Signed-off-by: Wanpeng Li <liwp@linux.vnet.ibm.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently, function should_fail() has "bool" for its return value, so it's
reasonable to change the return value of function should_fail_alloc_page()
into "bool" as well.
The patch does cleanup on function should_fail_alloc_page() to have "bool"
for its return value.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.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>
vm_stat_account() accounts the shared_vm, stack_vm and reserved_vm now.
But we can also account for total_vm in the vm_stat_account() which makes
the code tidy.
Even for mprotect_fixup(), we can get the right result in the end.
documentation: update how page-cluster affects swap I/O
Fix of the documentation of /proc/sys/vm/page-cluster to match the
behavior of the code and add some comments about what the tunable will
change in that behavior.
Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com> Acked-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Minchan Kim <minchan@kernel.org> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Swap readahead works fine, but the I/O to disk is almost always done in
page size requests, despite the fact that readahead submits
1<<page-cluster pages at a time.
On older kernels the old per device plugging behavior might have captured
this and merged the requests, but currently all comes down to much more
I/Os than required.
On a single device this might not be an issue, but as soon as a server
runs on shared san resources savin I/Os not only improves swapin
throughput but also provides a lower resource utilization.
With a load running KVM in a lot of memory overcommitment (the hot memory
is 1.5 times the host memory) swapping throughput improves significantly
and the lead feels more responsive as well as achieves more throughput.
In a test setup with 16 swap disks running blocktrace on one of those disks
shows the improved merging:
Prior:
Reads Queued: 560,888, 2,243MiB Writes Queued: 226,242, 904,968KiB
Read Dispatches: 544,701, 2,243MiB Write Dispatches: 159,318, 904,968KiB
Reads Requeued: 0 Writes Requeued: 0
Reads Completed: 544,716, 2,243MiB Writes Completed: 159,321, 904,980KiB
Read Merges: 16,187, 64,748KiB Write Merges: 61,744, 246,976KiB
IO unplugs: 149,614 Timer unplugs: 2,940
I got ~10% to ~40% more throughput in my cases and at the same time much
lower cpu consumption when broken down per transferred kilobyte (the
majority of that due to saved interrupts and better cache handling). In a
shared SAN others might get an additional benefit as well, because this
now causes less protocol overhead.
Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Minchan Kim <minchan@kernel.org> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jan Kara [Tue, 31 Jul 2012 23:41:37 +0000 (16:41 -0700)]
mm: make vb_alloc() more foolproof
If someone calls vb_alloc() (or vm_map_ram() for that matter) to allocate
0 bytes (0 pages), get_order() returns BITS_PER_LONG - PAGE_CACHE_SHIFT
and interesting stuff happens. So make debugging such problems easier and
warn about 0-size allocation.
[akpm@linux-foundation.org: use WARN_ON-return-value feature] Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
vmalloc: walk vmap_areas by sorted list instead of rb_next()
There's a walk by repeating rb_next to find a suitable hole. Could be
simply replaced by walk on the sorted vmap_area_list. More simpler and
efficient.
Mutation of the list and tree only happens in pair within
__insert_vmap_area and __free_vmap_area, under protection of
vmap_area_lock. The patch code is also under vmap_area_lock, so the list
walk is safe, and consistent with the tree walk.
Tested on SMP by repeating batch of vmalloc anf vfree for random sizes and
rounds for hours.
Signed-off-by: Hong Zhiguo <honkiko@gmail.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrew Morton [Tue, 31 Jul 2012 23:41:34 +0000 (16:41 -0700)]
drivers/media/video/v4l2-ioctl.c: fix build
Fix zillions of these:
drivers/media/video/v4l2-ioctl.c:1848: error: unknown field 'func' specified in initializer
drivers/media/video/v4l2-ioctl.c:1848: warning: missing braces around initializer
drivers/media/video/v4l2-ioctl.c:1848: warning: (near initialization for 'v4l2_ioctls[0].<anonymous>')
drivers/media/video/v4l2-ioctl.c:1848: warning: initialization makes integer from pointer without a cast
drivers/media/video/v4l2-ioctl.c:1848: error: initializer element is not computable at load time
drivers/media/video/v4l2-ioctl.c:1848: error: (near initialization for 'v4l2_ioctls[0].<anonymous>.offset')
block/blk-cgroup.c:609:2: error: unknown type name 'atomic64_t'
block/blk-cgroup.c:609:2: error: implicit declaration of function 'ATOMIC64_INIT' [-Werror=implicit-function-declaration]
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com> Cc: Chris Zankel <chris@zankel.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Akinobu Mita [Tue, 31 Jul 2012 23:41:31 +0000 (16:41 -0700)]
fault-injection: fix failcmd.sh warning
"fault-injection: add tool to run command with failslab or
fail_page_alloc" added tools/testing/fault-injection/failcmd.sh to make it
easier to inject slab/page allocation failures by fault injection.
failcmd.sh prints the following warning when running with arguments
for command.
Merge tag 'writeback-proportions' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux
Pull writeback updates from Wu Fengguang:
"Use time based periods to age the writeback proportions, which can
adapt equally well to fast/slow devices."
Fix up trivial conflict in comment in fs/sync.c
* tag 'writeback-proportions' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux:
writeback: Fix some comment errors
block: Convert BDI proportion calculations to flexible proportions
lib: Fix possible deadlock in flexible proportion code
lib: Proportions with flexible period
Merge tag 'nfs-for-3.6-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Features include:
- More preparatory patches for modularising NFSv2/v3/v4. Split out
the various NFSv2/v3/v4-specific code into separate files
- More preparation for the NFSv4 migration code
- Ensure that OPEN(O_CREATE) observes the pNFS mds threshold
parameters
- pNFS fast failover when the data servers are down
- Various cleanups and debugging patches"
* tag 'nfs-for-3.6-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (67 commits)
nfs: fix fl_type tests in NFSv4 code
NFS: fix pnfs regression with directio writes
NFS: fix pnfs regression with directio reads
sunrpc: clnt: Add missing braces
nfs: fix stub return type warnings
NFS: exit_nfs_v4() shouldn't be an __exit function
SUNRPC: Add a missing spin_unlock to gss_mech_list_pseudoflavors
NFS: Split out NFS v4 client functions
NFS: Split out the NFS v4 filesystem types
NFS: Create a single nfs_clone_super() function
NFS: Split out NFS v4 server creating code
NFS: Initialize the NFS v4 client from init_nfs_v4()
NFS: Move the v4 getroot code to nfs4getroot.c
NFS: Split out NFS v4 file operations
NFS: Initialize v4 sysctls from nfs_init_v4()
NFS: Create an init_nfs_v4() function
NFS: Split out NFS v4 inode operations
NFS: Split out NFS v3 inode operations
NFS: Split out NFS v2 inode operations
NFS: Clean up nfs4_proc_setclientid() and friends
...
Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull media updates from Mauro Carvalho Chehab:
"This is the first part of the media patches for v3.6.
This patch series contain:
- new DVB frontend: rtl2832
- new video drivers: adv7393
- some unused files got removed
- a selection API cleanup between V4L2 and V4L2 subdev API's
- a major redesign at v4l-ioctl2, in order to clean it up
- several driver fixes and improvements."
* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (174 commits)
v4l: Export v4l2-common.h in include/linux/Kbuild
media: Revert "[media] Terratec Cinergy S2 USB HD Rev.2"
[media] media: Use pr_info not homegrown pr_reg macro
[media] Terratec Cinergy S2 USB HD Rev.2
[media] v4l: Correct conflicting V4L2 subdev selection API documentation
[media] Feature removal: V4L2 selections API target and flag definitions
[media] v4l: Unify selection flags documentation
[media] v4l: Unify selection flags
[media] v4l: Common documentation for selection targets
[media] v4l: Unify selection targets across V4L2 and V4L2 subdev interfaces
[media] v4l: Remove "_ACTUAL" from subdev selection API target definition names
[media] V4L: Remove "_ACTIVE" from the selection target name definitions
[media] media: dvb-usb: print mac address via native %pM
[media] s5p-tv: Use module_i2c_driver in sii9234_drv.c file
[media] media: gpio-ir-recv: add allowed_protos for platform data
[media] s5p-jpeg: Use module_platform_driver in jpeg-core.c file
[media] saa7134: fix spelling of detach in label
[media] cx88-blackbird: replace ioctl by unlocked_ioctl
[media] cx88: don't use current_norm
[media] cx88: fix a number of v4l2-compliance violations
...
Merge Andrew's first set of patches:
"Non-MM patches:
- lots of misc bits
- tree-wide have_clk() cleanups
- quite a lot of printk tweaks. I draw your attention to "printk:
convert the format for KERN_<LEVEL> to a 2 byte pattern" which
looks a bit scary. But afaict it's solid.
- backlight updates
- lib/ feature work (notably the addition and use of memweight())
* Merge emailed patches from Andrew Morton <akpm@linux-foundation.org>: (128 commits)
drivers/misc/lkdtm.c: fix missing allocation failure check
lib/scatterlist: do not re-write gfp_flags in __sg_alloc_table()
fault-injection: add tool to run command with failslab or fail_page_alloc
fault-injection: add selftests for cpu and memory hotplug
powerpc: pSeries reconfig notifier error injection module
memory: memory notifier error injection module
PM: PM notifier error injection module
cpu: rewrite cpu-notifier-error-inject module
fault-injection: notifier error injection
c/r: fcntl: add F_GETOWNER_UIDS option
resource: make sure requested range is included in the root range
include/linux/aio.h: cpp->C conversions
fs: cachefiles: add support for large files in filesystem caching
pps: return PTR_ERR on error in device_create
taskstats: check nla_reserve() return
sysctl: suppress kmemleak messages
ipc: use Kconfig options for __ARCH_WANT_[COMPAT_]IPC_PARSE_VERSION
ipc: compat: use signed size_t types for msgsnd and msgrcv
ipc: allow compat IPC version field parsing if !ARCH_WANT_OLD_COMPAT_IPC
ipc: add COMPAT_SHMLBA support
...
lib/scatterlist: do not re-write gfp_flags in __sg_alloc_table()
We are seeing a lot of sg_alloc_table allocation failures using the new
drm prime infrastructure. We isolated the cause to code in
__sg_alloc_table that was re-writing the gfp_flags.
There is a comment in the code that suggest that there is an assumption
about the allocation coming from a memory pool. This was likely true
when sg lists were primarily used for disk I/O.
Signed-off-by: Mandeep Singh Baines <msb@chromium.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Cong Wang <amwang@redhat.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Rob Clark <rob.clark@linaro.org> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Inki Dae <inki.dae@samsung.com> Cc: Dave Airlie <airlied@redhat.com> Cc: Sonny Rao <sonnyrao@chromium.org> Cc: Olof Johansson <olofj@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Akinobu Mita [Mon, 30 Jul 2012 21:43:17 +0000 (14:43 -0700)]
fault-injection: add selftests for cpu and memory hotplug
This adds two selftests
* tools/testing/selftests/cpu-hotplug/on-off-test.sh is testing script
for CPU hotplug
1. Online all hot-pluggable CPUs
2. Offline all hot-pluggable CPUs
3. Online all hot-pluggable CPUs again
4. Exit if cpu-notifier-error-inject.ko is not available
5. Offline all hot-pluggable CPUs in preparation for testing
6. Test CPU hot-add error handling by injecting notifier errors
7. Online all hot-pluggable CPUs in preparation for testing
8. Test CPU hot-remove error handling by injecting notifier errors
* tools/testing/selftests/memory-hotplug/on-off-test.sh is doing the
similar thing for memory hotplug.
1. Online all hot-pluggable memory
2. Offline 10% of hot-pluggable memory
3. Online all hot-pluggable memory again
4. Exit if memory-notifier-error-inject.ko is not available
5. Offline 10% of hot-pluggable memory in preparation for testing
6. Test memory hot-add error handling by injecting notifier errors
7. Online all hot-pluggable memory in preparation for testing
8. Test memory hot-remove error handling by injecting notifier errors
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Suggested-by: Andrew Morton <akpm@linux-foundation.org> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Greg KH <greg@kroah.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <michael@ellerman.id.au> Cc: Dave Jones <davej@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This provides the ability to inject artifical errors to pSeries reconfig
notifier chain callbacks. It is controlled through debugfs interface
under /sys/kernel/debug/notifier-error-inject/pSeries-reconfig
If the notifier call chain should be failed with some events
notified, write the error code to "actions/<notifier event>/error".
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Greg KH <greg@kroah.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <michael@ellerman.id.au> Cc: Dave Jones <davej@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Akinobu Mita [Mon, 30 Jul 2012 21:43:10 +0000 (14:43 -0700)]
memory: memory notifier error injection module
This provides the ability to inject artifical errors to memory hotplug
notifier chain callbacks. It is controlled through debugfs interface
under /sys/kernel/debug/notifier-error-inject/memory
If the notifier call chain should be failed with some events notified,
write the error code to "actions/<notifier event>/error".
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Greg KH <greg@kroah.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <michael@ellerman.id.au> Cc: Dave Jones <davej@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Akinobu Mita [Mon, 30 Jul 2012 21:43:07 +0000 (14:43 -0700)]
PM: PM notifier error injection module
This provides the ability to inject artifical errors to PM notifier chain
callbacks. It is controlled through debugfs interface under
/sys/kernel/debug/notifier-error-inject/pm
Each of the files in "error" directory represents an event which can be
failed and contains the error code. If the notifier call chain should be
failed with some events notified, write the error code to the files.
If the notifier call chain should be failed with some events notified,
write the error code to "actions/<notifier event>/error".
Example: Inject PM suspend error (-12 = -ENOMEM)
# cd /sys/kernel/debug/notifier-error-inject/pm
# echo -12 > actions/PM_SUSPEND_PREPARE/error
# echo mem > /sys/power/state
bash: echo: write error: Cannot allocate memory
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Acked-by: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Pavel Machek <pavel@ucw.cz> Cc: Greg KH <greg@kroah.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <michael@ellerman.id.au> Cc: Dave Jones <davej@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Akinobu Mita [Mon, 30 Jul 2012 21:43:03 +0000 (14:43 -0700)]
cpu: rewrite cpu-notifier-error-inject module
Rewrite existing cpu-notifier-error-inject module to use debugfs based new
framework.
This change removes cpu_up_prepare_error and cpu_down_prepare_error module
parameters which were used to specify error code to be injected. We could
keep these module parameters for backward compatibility by module_param_cb
but it seems overkill for this module.
This provides the ability to inject artifical errors to CPU notifier chain
callbacks. It is controlled through debugfs interface under
/sys/kernel/debug/notifier-error-inject/cpu
If the notifier call chain should be failed with some events notified,
write the error code to "actions/<notifier event>/error".
Example1: inject CPU offline error (-1 == -EPERM)
# cd /sys/kernel/debug/notifier-error-inject/cpu
# echo -1 > actions/CPU_DOWN_PREPARE/error
# echo 0 > /sys/devices/system/cpu/cpu1/online
bash: echo: write error: Operation not permitted
Example2: inject CPU online error (-2 == -ENOENT)
# cd /sys/kernel/debug/notifier-error-inject/cpu
# echo -2 > actions/CPU_UP_PREPARE/error
# echo 1 > /sys/devices/system/cpu/cpu1/online
bash: echo: write error: No such file or directory
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Greg KH <greg@kroah.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <michael@ellerman.id.au> Cc: Dave Jones <davej@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Akinobu Mita [Mon, 30 Jul 2012 21:43:02 +0000 (14:43 -0700)]
fault-injection: notifier error injection
This patchset provides kernel modules that can be used to test the error
handling of notifier call chain failures by injecting artifical errors to
the following notifier chain callbacks.
# cd /sys/kernel/debug/notifier-error-inject/cpu
# echo -1 > actions/CPU_DOWN_PREPARE/error
# echo 0 > /sys/devices/system/cpu/cpu1/online
bash: echo: write error: Operation not permitted
The patchset also adds cpu and memory hotplug tests to
tools/testing/selftests These tests first do simple online and offline
test and then do fault injection tests if notifier error injection
module is available.
This patch:
The notifier error injection provides the ability to inject artifical
errors to specified notifier chain callbacks. It is useful to test the
error handling of notifier call chain failures.
This adds common basic functions to define which type of events can be
fail and to initialize the debugfs interface to control what error code
should be returned and which event should be failed.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Greg KH <greg@kroah.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <michael@ellerman.id.au> Cc: Dave Jones <davej@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
resource: make sure requested range is included in the root range
When the requested range is outside of the root range the logic in
__reserve_region_with_split will cause an infinite recursion which will
overflow the stack as seen in the warning bellow.
This particular stack overflow was caused by requesting the
(100000000-107ffffff) range while the root range was (0-ffffffff). In
this case __request_resource would return the whole root range as
conflict range (i.e. 0-ffffffff). Then, the logic in
__reserve_region_with_split would continue the recursion requesting the
new range as (conflict->end+1, end) which incidentally in this case
equals the originally requested range.
This patch aborts looking for an usable range when the request does not
intersect with the root range. When the request partially overlaps with
the root range, it ajust the request to fall in the root range and then
continues with the new request.
When the request is modified or aborted errors and a stack trace are
logged to allow catching the errors in the upper layers.
Andrew Morton [Mon, 30 Jul 2012 21:42:56 +0000 (14:42 -0700)]
include/linux/aio.h: cpp->C conversions
Convert init_sync_kiocb() from a nasty macro into a nice C function. The
struct assignment trick takes care of zeroing all unmentioned fields.
Shrinks fs/read_write.o's .text from 9857 bytes to 9714.
Also demacroize is_sync_kiocb() and aio_ring_avail(). The latter fixes an
arg-referenced-multiple-times hand grenade.
Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Mark Fasheh <mfasheh@suse.com> Acked-by: Jeff Moyer <jmoyer@redhat.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Emil Goode [Mon, 30 Jul 2012 21:42:51 +0000 (14:42 -0700)]
pps: return PTR_ERR on error in device_create
We should return PTR_ERR if the call to the device_create function fails.
Without this patch we instead return the value from a successful call to
cdev_add if the call to device_create fails.
Signed-off-by: Emil Goode <emilgoode@gmail.com> Acked-by: Devendra Naga <devendra.aaru@gmail.com> Cc: Alexander Gordeev <lasaine@lvk.cs.msu.su> Cc: Rodolfo Giometti <giometti@enneenne.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Steven Rostedt [Mon, 30 Jul 2012 21:42:48 +0000 (14:42 -0700)]
sysctl: suppress kmemleak messages
register_sysctl_table() is a strange function, as it makes internal
allocations (a header) to register a sysctl_table. This header is a
handle to the table that is created, and can be used to unregister the
table. But if the table is permanent and never unregistered, the header
acts the same as a static variable.
Unfortunately, this allocation of memory that is never expected to be
freed fools kmemleak in thinking that we have leaked memory. For those
sysctl tables that are never unregistered, and have no pointer referencing
them, kmemleak will think that these are memory leaks:
Will Deacon [Mon, 30 Jul 2012 21:42:46 +0000 (14:42 -0700)]
ipc: use Kconfig options for __ARCH_WANT_[COMPAT_]IPC_PARSE_VERSION
Rather than #define the options manually in the architecture code, add
Kconfig options for them and select them there instead. This also allows
us to select the compat IPC version parsing automatically for platforms
using the old compat IPC interface.
Reported-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Will Deacon [Mon, 30 Jul 2012 21:42:43 +0000 (14:42 -0700)]
ipc: compat: use signed size_t types for msgsnd and msgrcv
The msgsnd and msgrcv system calls use size_t to represent the size of the
message being transferred. POSIX states that values of msgsz greater than
SSIZE_MAX cause the result to be implementation-defined. On Linux, this
equates to returning -EINVAL if (long) msgsz < 0.
For compat tasks where !CONFIG_ARCH_WANT_OLD_COMPAT_IPC and compat_size_t
is smaller than size_t, negative size values passed from userspace will be
interpreted as positive values by do_msg{rcv,snd} and will fail to exit
early with -EINVAL.
This patch changes the compat prototypes for msg{rcv,snd} so that the
message size is represented as a compat_ssize_t, which we cast to the
native ssize_t type for the core IPC code.
Cc: Arnd Bergmann <arnd@arndb.de> Acked-by: Chris Metcalf <cmetcalf@tilera.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Will Deacon [Mon, 30 Jul 2012 21:42:40 +0000 (14:42 -0700)]
ipc: allow compat IPC version field parsing if !ARCH_WANT_OLD_COMPAT_IPC
Commit 48b25c43e6ee ("ipc: provide generic compat versions of IPC
syscalls") added a new ARCH_WANT_OLD_COMPAT_IPC config option for
architectures to select if their compat target requires the old IPC
syscall interface.
For architectures (such as AArch64) that do not require the internal
calling conventions provided by this option, but have a compat target
where the C library passes the IPC_64 flag explicitly,
compat_ipc_parse_version no longer strips out the flag before calling
the native system call implementation, resulting in unknown SHM/IPC
commands and -EINVAL being returned to userspace.
This patch separates the selection of the internal calling conventions
for the IPC syscalls from the version parsing, allowing architectures to
select __ARCH_WANT_COMPAT_IPC_PARSE_VERSION if they want to use version
parsing whilst retaining the newer syscall calling conventions.
Acked-by: Chris Metcalf <cmetcalf@tilera.com> Cc: Arnd Bergmann <arnd@arndb.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Will Deacon [Mon, 30 Jul 2012 21:42:38 +0000 (14:42 -0700)]
ipc: add COMPAT_SHMLBA support
If the SHMLBA definition for a native task differs from the definition for
a compat task, the do_shmat() function would need to handle both.
This patch introduces COMPAT_SHMLBA, which is used by the compat shmat
syscall when calling the ipc code and allows architectures such as AArch64
(where the native SHMLBA is 64k but the compat (AArch32) definition is
16k) to provide the correct semantics for compat IPC system calls.
Cc: David S. Miller <davem@davemloft.net> Cc: Chris Zankel <chris@zankel.net> Cc: Arnd Bergmann <arnd@arndb.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kdump: append newline to the last lien of vmcoreinfo note
The last line of vmcoreinfo note does not end with \n. Parsing all the
lines in note becomes easier if all lines end with \n instead of trying to
special case the last line.
I know at least one tool, vmcore-dmesg in kexec-tools tree which made the
assumption that all lines end with \n. I think it is a good idea to fix
it.
Error by 0) is not a matter, it can just return. But error by 1) requires
releasing task_struct allocated by 0) before it returns. Likewise, error
by 2) requires releasing task_struct and thread_info allocated by 0) and
1).
The existing error handling calls free_task_struct() and
free_thread_info() which do not only release task_struct and thread_info,
but also call architecture specific arch_release_task_struct() and
arch_release_thread_info().
The problem is that task_struct and thread_info are not fully initialized
yet at this point, but arch_release_task_struct() and
arch_release_thread_info() are called with them.
For example, x86 defines its own arch_release_task_struct() that releases
a task_xstate. If alloc_thread_info_node() fails in dup_task(),
arch_release_task_struct() is called with task_struct which is just
allocated and filled with garbage in this error handling.
This actually happened with tools/testing/fault-injection/failcmd.sh
In order to fix this issue, make free_{task_struct,thread_info}() not to
call arch_release_{task_struct,thread_info}() and call
arch_release_{task_struct,thread_info}() implicitly where needed.
Default arch_release_task_struct() and arch_release_thread_info() are
defined as empty by default. So this change only affects the
architectures which implement their own arch_release_task_struct() or
arch_release_thread_info() as listed below.
arch_release_task_struct(): x86, sh
arch_release_thread_info(): mn10300, tile
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: David Howells <dhowells@redhat.com> Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Salman Qazi <sqazi@google.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
proc: do not allow negative offsets on /proc/<pid>/environ
__mem_open() which is called by both /proc/<pid>/environ and
/proc/<pid>/mem ->open() handlers will allow the use of negative offsets.
/proc/<pid>/mem has negative offsets but not /proc/<pid>/environ.
Clean this by moving the 'force FMODE_UNSIGNED_OFFSET flag' to mem_open()
to allow negative offsets only on /proc/<pid>/mem.
proc: environ_read() make sure offset points to environment address range
Currently the following offset and environment address range check in
environ_read() of /proc/<pid>/environ is buggy:
int this_len = mm->env_end - (mm->env_start + src);
if (this_len <= 0)
break;
Large or negative offsets on /proc/<pid>/environ converted to 'unsigned
long' may pass this check since '(mm->env_start + src)' can overflow and
'this_len' will be positive.
This can turn /proc/<pid>/environ to act like /proc/<pid>/mem since
(mm->env_start + src) will point and read from another VMA.
There are two fixes here plus some code cleaning:
1) Fix the overflow by checking if the offset that was converted to
unsigned long will always point to the [mm->env_start, mm->env_end]
address range.
2) Remove the truncation that was made to the result of the check,
storing the result in 'int this_len' will alter its value and we can
not depend on it.
For kernels that have commit b409e578d ("proc: clean up
/proc/<pid>/environ handling") which adds the appropriate ptrace check and
saves the 'mm' at ->open() time, this is not a security issue.
This patch is taken from the grsecurity patch since it was just made
available.
coredump: fix wrong comments on core limits of pipe coredump case
In commit 898b374af6f7 ("exec: replace call_usermodehelper_pipe with use
of umh init function and resolve limit"), the core limits recursive
check value was changed from 0 to 1, but the corresponding comments were
not updated.
Signed-off-by: Jovi Zhang <bookjovi@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The system deadlocks (at least since 2.6.10) when
call_usermodehelper(UMH_WAIT_EXEC) request triggers
call_usermodehelper(UMH_WAIT_PROC) request.
This is because "khelper thread is waiting for the worker thread at
wait_for_completion() in do_fork() since the worker thread was created
with CLONE_VFORK flag" and "the worker thread cannot call complete()
because do_execve() is blocked at UMH_WAIT_PROC request" and "the khelper
thread cannot start processing UMH_WAIT_PROC request because the khelper
thread is waiting for the worker thread at wait_for_completion() in
do_fork()".
The easiest example to observe this deadlock is to use a corrupted
/sbin/hotplug binary (like shown below).
call_usermodehelper("/tmp/dummy", UMH_WAIT_EXEC) is called from
kobject_uevent_env() in lib/kobject_uevent.c upon loading/unloading a
module. do_execve("/tmp/dummy") triggers a call to
request_module("binfmt-0000") from search_binary_handler() which in turn
calls call_usermodehelper(UMH_WAIT_PROC).
In order to avoid deadlock, as a for-now and easy-to-backport solution, do
not try to call wait_for_completion() in call_usermodehelper_exec() if the
worker thread was created by khelper thread with CLONE_VFORK flag. Future
and fundamental solution might be replacing singleton khelper thread with
some workqueue so that recursive calls up to max_active dependency loop
can be handled without deadlock.
[akpm@linux-foundation.org: add comment to kmod_thread_locker] Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Tejun Heo <tj@kernel.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>
Nearly identical shortname parsing is performed in fat_search_long() and
__fat_readdir(). Extract this code into a function that may be called by
both.
Signed-off-by: Steven J. Magnani <steve@digidescorp.com> Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
where the thaw ioctl deadlocked at thaw_super() when called while chcp was
waiting at nilfs_transaction_begin() called from
nilfs_ioctl_change_cpmode(). This deadlock is 100% reproducible.
This is because nilfs_ioctl_change_cpmode() first locks sb->s_umount in
read mode and then waits for unfreezing in nilfs_transaction_begin(),
whereas thaw_super() locks sb->s_umount in write mode. The locking of
sb->s_umount here was intended to make snapshot mounts and the downgrade
of snapshots to checkpoints exclusive.
This fixes the deadlock issue by replacing the sb->s_umount usage in
nilfs_ioctl_change_cpmode() with a dedicated mutex which protects snapshot
mounts.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp> Tested-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
nilfs2: fix timing issue between rmcp and chcp ioctls
The checkpoint deletion ioctl (rmcp ioctl) has potential for breaking
snapshot because it is not fully exclusive with checkpoint mode change
ioctl (chcp ioctl).
The rmcp ioctl first tests if the specified checkpoint is a snapshot or
not within nilfs_cpfile_delete_checkpoint function, and then calls
nilfs_cpfile_delete_checkpoints function to actually invalidate the
checkpoint only if it's not a snapshot. However, the checkpoint can be
changed into a snapshot by the chcp ioctl between these two operations.
In that case, calling nilfs_cpfile_delete_checkpoints() wrongly
invalidates the snapshot, which leads to snapshot list corruption and
snapshot count mismatch.
This fixes the issue by changing nilfs_cpfile_delete_checkpoints() so
that it reconfirms the target checkpoints are snapshot or not.
This second check is exclusive with the chcp operation since it is
protected by an existing semaphore.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
nilfs2: remove references to long gone super operations
->delete_inode(), ->write_super_lockfs(), ->unlockfs() are gone so remove
references to them in the NTFS code. Noticed while cleaning up the
fsfreeze mess.
Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On minix2 and minix3 usually max_size is 7fffffff and the check in
question prohibits creation of last block spanning right before 7fffffff,
due to downward rounding during the division. Fix it by using
multiplication instead.
[akpm@linux-foundation.org: fix up code layout, use local `sb'] Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Nick Bowler [Mon, 30 Jul 2012 21:41:57 +0000 (14:41 -0700)]
drivers/rtc/rtc-pcf8563.c: set owner field in driver struct
The owner member is supposed to be set to the module implementing the
device driver, i.e., THIS_MODULE. This enables the appropriate module
link in sysfs.
Signed-off-by: Nick Bowler <nbowler@elliptictech.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrew Morton [Mon, 30 Jul 2012 21:41:47 +0000 (14:41 -0700)]
drivers/rtc/rtc-r9701.c: check that r9701_set_datetime() succeeded
When the driver detects that the clock time is invalid, it attempts to
write a sane time into the hardware. We curently assume that everything
is OK if those writes succeeded. But it is better to re-read the time
from the hardware to ensure that the new settings got there OK.
drivers/rtc/rtc-r9701.c: avoid second call to rtc_valid_tm()
r9701_get_datetime() calls rtc_valid_tm() and returns the value returned
by rtc_valid_tm(), which can be used in the `if', so calling
rtc_valid_tm() a second time is not required.
The pl031 interrupt is shared between the timer part and the clockwatch
part of the same HW block on the ux500, so mark it IRQF_SHARED on this
variant.
This patch also adds the IRQF_NO_SUSPEND flag to the rtc irq on all
variants as we don't want this pretty important IRQ to be disabled in
suspend.