The commit 96d0df79f2 ("proc: make proc_fd_permission() thread-friendly")
fixed the access to /proc/self/fd from sub-threads, but introduced another
problem: a sub-thread can't access /proc/<tid>/fd/ or /proc/thread-self/fd
if generic_permission() fails.
Change proc_fd_permission() to check same_thread_group(pid_task(), current).
Fixes: 96d0df79f2 ("proc: make proc_fd_permission() thread-friendly")
Reported-by: "Jin, Yihua" <yihua.jin@intel.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For now in task_name() we ignore the return code of string_escape_str()
call. This is not good if buffer suddenly becomes not big enough. Do the
proper error handling there.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
sync_file_range(2) is documented to issue writeback only for pages that
are not currently being written. After all the system call has been
created for userspace to be able to issue background writeout and so
waiting for in-flight IO is undesirable there. However commit
ee53a891f4 ("mm: do_sync_mapping_range integrity fix") switched
do_sync_mapping_range() and thus sync_file_range() to issue writeback in
WB_SYNC_ALL mode since do_sync_mapping_range() was used by other code
relying on WB_SYNC_ALL semantics.
These days do_sync_mapping_range() went away and we can switch
sync_file_range(2) back to issuing WB_SYNC_NONE writeback. That should
help PostgreSQL avoid large latency spikes when flushing data in the
background.
Andres measured a 20% increase in transactions per second on an SSD disk.
Signed-off-by: Jan Kara <jack@suse.com>
Reported-by: Andres Freund <andres@anarazel.de>
Tested-By: Andres Freund <andres@anarazel.de>
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>
There are many places which use mapping_gfp_mask to restrict a more
generic gfp mask which would be used for allocations which are not
directly related to the page cache but they are performed in the same
context.
Let's introduce a helper function which makes the restriction explicit and
easier to track. This patch doesn't introduce any functional changes.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Michal Hocko <mhocko@suse.com>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
__GFP_WAIT was used to signal that the caller was in atomic context and
could not sleep. Now it is possible to distinguish between true atomic
context and callers that are not willing to sleep. The latter should
clear __GFP_DIRECT_RECLAIM so kswapd will still wake. As clearing
__GFP_WAIT behaves differently, there is a risk that people will clear the
wrong flags. This patch renames __GFP_WAIT to __GFP_RECLAIM to clearly
indicate what it does -- setting it allows all reclaim activity, clearing
them prevents it.
[akpm@linux-foundation.org: fix build]
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Christoph Lameter <cl@linux.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Vitaly Wool <vitalywool@gmail.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>
__GFP_WAIT has been used to identify atomic context in callers that hold
spinlocks or are in interrupts. They are expected to be high priority and
have access one of two watermarks lower than "min" which can be referred
to as the "atomic reserve". __GFP_HIGH users get access to the first
lower watermark and can be called the "high priority reserve".
Over time, callers had a requirement to not block when fallback options
were available. Some have abused __GFP_WAIT leading to a situation where
an optimisitic allocation with a fallback option can access atomic
reserves.
This patch uses __GFP_ATOMIC to identify callers that are truely atomic,
cannot sleep and have no alternative. High priority users continue to use
__GFP_HIGH. __GFP_DIRECT_RECLAIM identifies callers that can sleep and
are willing to enter direct reclaim. __GFP_KSWAPD_RECLAIM to identify
callers that want to wake kswapd for background reclaim. __GFP_WAIT is
redefined as a caller that is willing to enter direct reclaim and wake
kswapd for background reclaim.
This patch then converts a number of sites
o __GFP_ATOMIC is used by callers that are high priority and have memory
pools for those requests. GFP_ATOMIC uses this flag.
o Callers that have a limited mempool to guarantee forward progress clear
__GFP_DIRECT_RECLAIM but keep __GFP_KSWAPD_RECLAIM. bio allocations fall
into this category where kswapd will still be woken but atomic reserves
are not used as there is a one-entry mempool to guarantee progress.
o Callers that are checking if they are non-blocking should use the
helper gfpflags_allow_blocking() where possible. This is because
checking for __GFP_WAIT as was done historically now can trigger false
positives. Some exceptions like dm-crypt.c exist where the code intent
is clearer if __GFP_DIRECT_RECLAIM is used instead of the helper due to
flag manipulations.
o Callers that built their own GFP flags instead of starting with GFP_KERNEL
and friends now also need to specify __GFP_KSWAPD_RECLAIM.
The first key hazard to watch out for is callers that removed __GFP_WAIT
and was depending on access to atomic reserves for inconspicuous reasons.
In some cases it may be appropriate for them to use __GFP_HIGH.
The second key hazard is callers that assembled their own combination of
GFP flags instead of starting with something like GFP_KERNEL. They may
now wish to specify __GFP_KSWAPD_RECLAIM. It's almost certainly harmless
if it's missed in most cases as other activity will wake kswapd.
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Vitaly Wool <vitalywool@gmail.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>
Merge patch-bomb from Andrew Morton:
- inotify tweaks
- some ocfs2 updates (many more are awaiting review)
- various misc bits
- kernel/watchdog.c updates
- Some of mm. I have a huge number of MM patches this time and quite a
lot of it is quite difficult and much will be held over to next time.
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (162 commits)
selftests: vm: add tests for lock on fault
mm: mlock: add mlock flags to enable VM_LOCKONFAULT usage
mm: introduce VM_LOCKONFAULT
mm: mlock: add new mlock system call
mm: mlock: refactor mlock, munlock, and munlockall code
kasan: always taint kernel on report
mm, slub, kasan: enable user tracking by default with KASAN=y
kasan: use IS_ALIGNED in memory_is_poisoned_8()
kasan: Fix a type conversion error
lib: test_kasan: add some testcases
kasan: update reference to kasan prototype repo
kasan: move KASAN_SANITIZE in arch/x86/boot/Makefile
kasan: various fixes in documentation
kasan: update log messages
kasan: accurately determine the type of the bad access
kasan: update reported bug types for kernel memory accesses
kasan: update reported bug types for not user nor kernel memory accesses
mm/kasan: prevent deadlock in kasan reporting
mm/kasan: don't use kasan shadow pointer in generic functions
mm/kasan: MODULE_VADDR is not available on all archs
...
This fixes a bug from commit f3f86e33dc ("vfs: Fix pathological
performance case for __alloc_fd()").
v2: refactor to share fd bitmap copying code
Signed-off-by: Eric Biggers <ebiggers3@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
/proc/pid/oom_adj exists solely to avoid breaking existing userspace
binaries that write to the tunable.
Add a comment in the only possible location within the kernel tree to
describe the situation and motivation for keeping it around.
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As mentioned in the commit 56eecdb912 ("mm: Use ptep/pmdp_set_numa()
for updating _PAGE_NUMA bit"), architectures like ppc64 don't do tlb
flush in set_pte/pmd functions.
So when dealing with existing pte in clear_soft_dirty, the pte must be
cleared before being modified.
Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
filemap_fdatawait() is a function to wait for on-going writeback to
complete but also consume and clear error status of the mapping set during
writeback.
The latter functionality is critical for applications to detect writeback
error with system calls like fsync(2)/fdatasync(2).
However filemap_fdatawait() is also used by sync(2) or FIFREEZE ioctl,
which don't check error status of individual mappings.
As a result, fsync() may not be able to detect writeback error if events
happen in the following order:
Application System admin
----------------------------------------------------------
write data on page cache
Run sync command
writeback completes with error
filemap_fdatawait() clears error
fsync returns success
(but the data is not on disk)
This patch adds filemap_fdatawait_keep_errors() for call sites where
writeback error is not handled so that they don't clear error status.
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Tejun Heo <tj@kernel.org>
Cc: Fengguang Wu <fengguang.wu@gmail.com>
Cc: Dave Chinner <david@fromorbit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently there's no easy way to get per-process usage of hugetlb pages,
which is inconvenient because userspace applications which use hugetlb
typically want to control their processes on the basis of how much memory
(including hugetlb) they use. So this patch simply provides easy access
to the info via /proc/PID/status.
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Joern Engel <joern@logfs.org>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If the remote locking fail, we run a local vfs unlock that should work and
return success to userland when we didn't actually lock at all. We need
to tell the application that tried to lock that it didn't get it, not that
all went well.
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
readahead_pages in ocfs2_duplicate_clusters_by_page is defined but not
used, so clean it up.
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.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>
A node can mount multiple ocfs2 volumes. And if thread names are same for
each volume/domain, it will bring inconvenience when analyzing problems
because we have to identify which volume/domain the messages belong to.
Since thread name will be printed to messages, so add volume uuid or dlm
name to thread name can benefit problem analysis.
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Gang He <ghe@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In ocfs2_mknod_locked if '__ocfs2_mknod_locke d' returns an error, we
should reclaim the inode successfully claimed above, otherwise, the
inode never be reused. The case is described below:
ocfs2_mknod
ocfs2_mknod_locked
ocfs2_claim_new_inode
Successfully claim the inode
__ocfs2_mknod_locked
ocfs2_journal_access_di
Failed because of -ENOMEM or other reasons, the inode
lockres has not been initialized yet.
iput(inode)
ocfs2_evict_inode
ocfs2_delete_inode
ocfs2_inode_lock
ocfs2_inode_lock_full_nested
__ocfs2_cluster_lock
Return -EINVAL because of the inode
lockres has not been initialized.
So the following operations are not performed
ocfs2_wipe_inode
ocfs2_remove_inode
ocfs2_free_dinode
ocfs2_free_suballoc_bits
Signed-off-by: Alex Chen <alex.chen@huawei.com>
Reviewed-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There is a race case between mount and delete node/cluster, which will
lead o2hb_thread to malfunctioning dead loop.
o2hb_thread
{
o2nm_depend_this_node();
<<<<<< race window, node may have already been deleted, and then
enter the loop, o2hb thread will be malfunctioning
because of no configured nodes found.
while (!kthread_should_stop() &&
!reg->hr_unclean_stop && !reg->hr_aborted_start) {
}
So check the return value of o2nm_depend_this_node() is needed. If node
has been deleted, do not enter the loop and let mount fail.
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.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>
We have no need to take inode mutex, rw and inode lock if it is not dio
entry when recover orphans. Optimize it by adding a flag
OCFS2_INODE_DIO_ORPHAN_ENTRY to ocfs2_inode_info to reduce contention.
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
dio entry will only do truncate in case of ORPHAN_NEED_TRUNCATE. So do
not include it when doing normal orphan scan to reduce contention.
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently cluster allocation is always trying to find a victim chain (a
chian has most space), and this may lead to poor performance because of
discontiguous allocation in some scenarios.
Our test case is block size 4k, cluster size 1M and mount option with
localalloc=2048 (2G), since a gd is 32256M (about 31.5G) and a localalloc
window is only 2G, creating 50G file will result in 2G from gd0, 2G from
gd1, ...
One way to improve performance is enlarge localalloc window size (max
31104M), but this will make end user feel that about 30G is suddenly
"missing", and localalloc currently do not support steal, which means one
node cannot use another node's localalloc even it is not used in fact. So
using the last gd to record the allocation and continues with the gd if it
has enough space for a localalloc window can make the allocation as more
contiguous as possible.
Our test result is below (evaluated in IOPS), which is using iometer
running in VM, dynamic vhd virtual disk stored in ocfs2.
IO model Original After Improved(%)
16K60%Write100%Random 703 876 24.59%
8K90%Write100%Random 735 827 12.59%
4K100%Write100%Random 859 915 6.52%
4K100%Read100%Random 2092 2600 24.30%
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Tested-by: Norton Zhu <norton.zhu@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A simplified test case is (this case from Ryan):
1) dd if=/dev/zero of=/mnt/hello bs=512 count=1 oflag=direct;
2) truncate /mnt/hello -s 2097152
file 'hello' is not exist before test. After this command,
file 'hello' should be all zero. But 512~4096 is some random data.
Setting bh state to new when get a new block, if so,
direct_io_worker()->dio_zero_block() will fill-in the unused portion
of the block with zero.
Signed-off-by: Yiwen Jiang <jiangyiwen@huawei.com>
Reviewed-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If ocfs2_is_overwrite failed, ocfs2_direct_IO_write mays till return
success to the caller.
Signed-off-by: Norton.Zhu <norton.zhu@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fs/logfs/dev_bdev.c: In function '__bdev_writeseg':
include/linux/kernel.h:601:17: warning: comparison of distinct pointer types lacks a cast [enabled by default]
(void) (&_min1 == &_min2); \
fs/logfs/dev_bdev.c:84:14: note: in expansion of macro 'min'
max_pages = min(nr_pages, BIO_MAX_PAGES);
fs/logfs/dev_bdev.c: In function 'do_erase':
include/linux/kernel.h:601:17: warning: comparison of distinct pointer types lacks a cast [enabled by default]
(void) (&_min1 == &_min2); \
fs/logfs/dev_bdev.c:174:14: note: in expansion of macro 'min'
max_pages = min(nr_pages, BIO_MAX_PAGES);
Lets use min_t and mention the type.
Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Cc: Joern Engel <joern@logfs.org>
Cc: Prasad Joshi <prasadjoshi.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The comment here says that it is checking for invalid bits. But, the mask
is *actually* checking to ensure that _any_ valid bit is set, which is
quite different.
Without this check, an unexpected bit could get set on an inotify object.
Since these bits are also interpreted by the fsnotify/dnotify code, there
is the potential for an object to be mishandled inside the kernel. For
instance, can we be sure that setting the dnotify flag FS_DN_RENAME on an
inotify watch is harmless?
Add the actual check which was intended. Retain the existing inotify bits
are being added to the watch. Plus, this is existing behavior which would
be nice to preserve.
I did a quick sniff test that inotify functions and that my
'inotify-tools' package passes 'make check'.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: John McCutchan <john@johnmccutchan.com>
Cc: Robert Love <rlove@rlove.org>
Cc: Eric Paris <eparis@parisplace.org>
Cc: Josh Boyer <jwboyer@fedoraproject.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There was a report that my patch:
inotify: actually check for invalid bits in sys_inotify_add_watch()
broke CRIU.
The reason is that CRIU looks up raw flags in /proc/$pid/fdinfo/* to
figure out how to rebuild inotify watches and then passes those flags
directly back in to the inotify API. One of those flags
(FS_EVENT_ON_CHILD) is set in mark->mask, but is not part of the inotify
API. It is used inside the kernel to _implement_ inotify but it is not
and has never been part of the API.
My patch above ensured that we only allow bits which are part of the API
(IN_ALL_EVENTS). This broke CRIU.
FS_EVENT_ON_CHILD is really internal to the kernel. It is set _anyway_ on
all inotify marks. So, CRIU was really just trying to set a bit that was
already set.
This patch hides that bit from fdinfo. CRIU will not see the bit, not try
to set it, and should work as before. We should not have been exposing
this bit in the first place, so this is a good patch independent of the
CRIU problem.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reported-by: Andrey Wagin <avagin@gmail.com>
Acked-by: Andrey Vagin <avagin@openvz.org>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Eric Paris <eparis@redhat.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: John McCutchan <john@johnmccutchan.com>
Cc: Robert Love <rlove@rlove.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull security subsystem update from James Morris:
"This is mostly maintenance updates across the subsystem, with a
notable update for TPM 2.0, and addition of Jarkko Sakkinen as a
maintainer of that"
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (40 commits)
apparmor: clarify CRYPTO dependency
selinux: Use a kmem_cache for allocation struct file_security_struct
selinux: ioctl_has_perm should be static
selinux: use sprintf return value
selinux: use kstrdup() in security_get_bools()
selinux: use kmemdup in security_sid_to_context_core()
selinux: remove pointless cast in selinux_inode_setsecurity()
selinux: introduce security_context_str_to_sid
selinux: do not check open perm on ftruncate call
selinux: change CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE default
KEYS: Merge the type-specific data with the payload data
KEYS: Provide a script to extract a module signature
KEYS: Provide a script to extract the sys cert list from a vmlinux file
keys: Be more consistent in selection of union members used
certs: add .gitignore to stop git nagging about x509_certificate_list
KEYS: use kvfree() in add_key
Smack: limited capability for changing process label
TPM: remove unnecessary little endian conversion
vTPM: support little endian guests
char: Drop owner assignment from i2c_driver
...
Pull userns hardlink capability check fix from Eric Biederman:
"This round just contains a single patch. There has been a lot of
other work this period but it is not quite ready yet, so I am pushing
it until 4.5.
The remaining change by Dirk Steinmetz wich fixes both Gentoo and
Ubuntu containers allows hardlinks if we have the appropriate
capabilities in the user namespace. Security wise it is really a
gimme as the user namespace root can already call setuid become that
user and create the hardlink"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
namei: permit linking with CAP_FOWNER in userns
backend drivers to be unloaded.
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Merge tag 'please-pull-pstore' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux
Pull pstore updates from Tony Luck:
"Half dozen small cleanups plus change to allow pstore backend drivers
to be unloaded"
* tag 'please-pull-pstore' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux:
pstore: fix code comment to match code
efi-pstore: fix kernel-doc argument name
pstore: Fix return type of pstore_is_mounted()
pstore: add pstore unregister
pstore: add a helper function pstore_register_kmsg
pstore: add vmalloc error check
Pull f2fs updates from Jaegeuk Kim:
"Most part of the patches include enhancing the stability and
performance of in-memory extent caches feature.
In addition, it introduces several new features and configurable
points:
- F2FS_GOING_DOWN_METAFLUSH ioctl to test power failures
- F2FS_IOC_WRITE_CHECKPOINT ioctl to trigger checkpoint by users
- background_gc=sync mount option to do gc synchronously
- periodic checkpoints
- sysfs entry to control readahead blocks for free nids
And the following bug fixes have been merged.
- fix SSA corruption by collapse/insert_range
- correct a couple of gc behaviors
- fix the results of f2fs_map_blocks
- fix error case handling of volatile/atomic writes"
* tag 'for-f2fs-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (54 commits)
f2fs: fix to skip shrinking extent nodes
f2fs: fix error path of ->symlink
f2fs: fix to clear GCed flag for atomic written page
f2fs: don't need to submit bio on error case
f2fs: fix leakage of inmemory atomic pages
f2fs: refactor __find_rev_next_{zero}_bit
f2fs: support fiemap for inline_data
f2fs: flush dirty data for bmap
f2fs: relocate the tracepoint for background_gc
f2fs crypto: fix racing of accessing encrypted page among
f2fs: export ra_nid_pages to sysfs
f2fs: readahead for free nids building
f2fs: support lower priority asynchronous readahead in ra_meta_pages
f2fs: don't tag REQ_META for temporary non-meta pages
f2fs: add a tracepoint for f2fs_read_data_pages
f2fs: set GFP_NOFS for grab_cache_page
f2fs: fix SSA updates resulting in corruption
Revert "f2fs: do not skip dentry block writes"
f2fs: add F2FS_GOING_DOWN_METAFLUSH to test power-failure
f2fs: merge meta writes as many possible
...
This includes one simple fix to make posix locks
interruptible by signals in cases where a signal
handler is used.
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Merge tag 'dlm-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm
Pull dlm update from David Teigland:
"This includes one simple fix to make posix locks interruptible by
signals in cases where a signal handler is used"
* tag 'dlm-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm:
dlm: make posix locks interruptible
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Merge tag 'locks-v4.4-1' of git://git.samba.org/jlayton/linux
Pull file locking updates from Jeff Layton:
"The largest series of changes is from Ben who offered up a set to add
a new helper function for setting locks based on the type set in
fl_flags. Dmitry also send in a fix for a potential race that he
found with KTSAN"
* tag 'locks-v4.4-1' of git://git.samba.org/jlayton/linux:
locks: cleanup posix_lock_inode_wait and flock_lock_inode_wait
Move locks API users to locks_lock_inode_wait()
locks: introduce locks_lock_inode_wait()
locks: Use more file_inode and fix a comment
fs: fix data races on inode->i_flctx
locks: change tracepoint for generic_add_lease
Here's the "big" driver core updates for 4.4-rc1. Primarily a bunch of
debugfs updates, with a smattering of minor driver core fixes and
updates as well.
All have been in linux-next for a long time.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-4.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
"Here's the "big" driver core updates for 4.4-rc1. Primarily a bunch
of debugfs updates, with a smattering of minor driver core fixes and
updates as well.
All have been in linux-next for a long time"
* tag 'driver-core-4.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
debugfs: Add debugfs_create_ulong()
of: to support binding numa node to specified device in devicetree
debugfs: Add read-only/write-only bool file ops
debugfs: Add read-only/write-only size_t file ops
debugfs: Add read-only/write-only x64 file ops
debugfs: Consolidate file mode checks in debugfs_create_*()
Revert "mm: Check if section present during memory block (un)registering"
driver-core: platform: Provide helpers for multi-driver modules
mm: Check if section present during memory block (un)registering
devres: fix a for loop bounds check
CMA: fix CONFIG_CMA_SIZE_MBYTES overflow in 64bit
base/platform: assert that dev_pm_domain callbacks are called unconditionally
sysfs: correctly handle short reads on PREALLOC attrs.
base: soc: siplify ida usage
kobject: move EXPORT_SYMBOL() macros next to corresponding definitions
kobject: explain what kobject's sd field is
debugfs: document that debugfs_remove*() accepts NULL and error values
debugfs: Pass bool pointer to debugfs_create_bool()
ACPI / EC: Fix broken 64bit big-endian users of 'global_lock'
Pull block integrity updates from Jens Axboe:
""This is the joint work of Dan and Martin, cleaning up and improving
the support for block data integrity"
* 'for-4.4/integrity' of git://git.kernel.dk/linux-block:
block, libnvdimm, nvme: provide a built-in blk_integrity nop profile
block: blk_flush_integrity() for bio-based drivers
block: move blk_integrity to request_queue
block: generic request_queue reference counting
nvme: suspend i/o during runtime blk_integrity_unregister
md: suspend i/o during runtime blk_integrity_unregister
md, dm, scsi, nvme, libnvdimm: drop blk_integrity_unregister() at shutdown
block: Inline blk_integrity in struct gendisk
block: Export integrity data interval size in sysfs
block: Reduce the size of struct blk_integrity
block: Consolidate static integrity profile properties
block: Move integrity kobject to struct gendisk
Pull core block updates from Jens Axboe:
"This is the core block pull request for 4.4. I've got a few more
topic branches this time around, some of them will layer on top of the
core+drivers changes and will come in a separate round. So not a huge
chunk of changes in this round.
This pull request contains:
- Enable blk-mq page allocation tracking with kmemleak, from Catalin.
- Unused prototype removal in blk-mq from Christoph.
- Cleanup of the q->blk_trace exchange, using cmpxchg instead of two
xchg()'s, from Davidlohr.
- A plug flush fix from Jeff.
- Also from Jeff, a fix that means we don't have to update shared tag
sets at init time unless we do a state change. This cuts down boot
times on thousands of devices a lot with scsi/blk-mq.
- blk-mq waitqueue barrier fix from Kosuke.
- Various fixes from Ming:
- Fixes for segment merging and splitting, and checks, for
the old core and blk-mq.
- Potential blk-mq speedup by marking ctx pending at the end
of a plug insertion batch in blk-mq.
- direct-io no page dirty on kernel direct reads.
- A WRITE_SYNC fix for mpage from Roman"
* 'for-4.4/core' of git://git.kernel.dk/linux-block:
blk-mq: avoid excessive boot delays with large lun counts
blktrace: re-write setting q->blk_trace
blk-mq: mark ctx as pending at batch in flush plug path
blk-mq: fix for trace_block_plug()
block: check bio_mergeable() early before merging
blk-mq: check bio_mergeable() early before merging
block: avoid to merge splitted bio
block: setup bi_phys_segments after splitting
block: fix plug list flushing for nomerge queues
blk-mq: remove unused blk_mq_clone_flush_request prototype
blk-mq: fix waitqueue_active without memory barrier in block/blk-mq-tag.c
fs: direct-io: don't dirtying pages for ITER_BVEC/ITER_KVEC direct read
fs/mpage.c: forgotten WRITE_SYNC in case of data integrity write
block: kmemleak: Track the page allocations for struct request
Pull s390 updates from Martin Schwidefsky:
"There is only one new feature in this pull for the 4.4 merge window,
most of it is small enhancements, cleanup and bug fixes:
- Add the s390 backend for the software dirty bit tracking. This
adds two new pgtable functions pte_clear_soft_dirty and
pmd_clear_soft_dirty which is why there is a hit to
arch/x86/include/asm/pgtable.h in this pull request.
- A series of cleanup patches for the AP bus, this includes the
removal of the support for two outdated crypto cards (PCICC and
PCICA).
- The irq handling / signaling on buffer full in the runtime
instrumentation code is dropped.
- Some micro optimizations: remove unnecessary memory barriers for a
couple of functions: [smb_]rmb, [smb_]wmb, atomics, bitops, and for
spin_unlock. Use the builtin bswap if available and make
test_and_set_bit_lock more cache friendly.
- Statistics and a tracepoint for the diagnose calls to the
hypervisor.
- The CPU measurement facility support to sample KVM guests is
improved.
- The vector instructions are now always enabled for user space
processes if the hardware has the vector facility. This simplifies
the FPU handling code. The fpu-internal.h header is split into fpu
internals, api and types just like x86.
- Cleanup and improvements for the common I/O layer.
- Rework udelay to solve a problem with kprobe. udelay has busy loop
semantics but still uses an idle processor state for the wait"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (66 commits)
s390: remove runtime instrumentation interrupts
s390/cio: de-duplicate subchannel validation
s390/css: unneeded initialization in for_each_subchannel
s390/Kconfig: use builtin bswap
s390/dasd: fix disconnected device with valid path mask
s390/dasd: fix invalid PAV assignment after suspend/resume
s390/dasd: fix double free in dasd_eckd_read_conf
s390/kernel: fix ptrace peek/poke for floating point registers
s390/cio: move ccw_device_stlck functions
s390/cio: move ccw_device_call_handler
s390/topology: reduce per_cpu() invocations
s390/nmi: reduce size of percpu variable
s390/nmi: fix terminology
s390/nmi: remove casts
s390/nmi: remove pointless error strings
s390: don't store registers on disabled wait anymore
s390: get rid of __set_psw_mask()
s390/fpu: split fpu-internal.h into fpu internals, api, and type headers
s390/dasd: fix list_del corruption after lcu changes
s390/spinlock: remove unneeded serializations at unlock
...
Pull RCU changes from Ingo Molnar:
"The main changes in this cycle were:
- Improvements to expedited grace periods (Paul E McKenney)
- Performance improvements to and locktorture tests for percpu-rwsem
(Oleg Nesterov, Paul E McKenney)
- Torture-test changes (Paul E McKenney, Davidlohr Bueso)
- Documentation updates (Paul E McKenney)
- Miscellaneous fixes (Paul E McKenney, Boqun Feng, Oleg Nesterov,
Patrick Marlier)"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits)
fs/writeback, rcu: Don't use list_entry_rcu() for pointer offsetting in bdi_split_work_to_wbs()
rcu: Better hotplug handling for synchronize_sched_expedited()
rcu: Enable stall warnings for synchronize_rcu_expedited()
rcu: Add tasks to expedited stall-warning messages
rcu: Add online/offline info to expedited stall warning message
rcu: Consolidate expedited CPU selection
rcu: Prepare for consolidating expedited CPU selection
cpu: Remove try_get_online_cpus()
rcu: Stop excluding CPU hotplug in synchronize_sched_expedited()
rcu: Stop silencing lockdep false positive for expedited grace periods
rcu: Switch synchronize_sched_expedited() to IPI
locktorture: Fix module unwind when bad torture_type specified
torture: Forgive non-plural arguments
rcutorture: Fix unused-function warning for torturing_tasks()
rcutorture: Fix module unwind when bad torture_type specified
rcu_sync: Cleanup the CONFIG_PROVE_RCU checks
locking/percpu-rwsem: Clean up the lockdep annotations in percpu_down_read()
locking/percpu-rwsem: Fix the comments outdated by rcu_sync
locking/percpu-rwsem: Make use of the rcu_sync infrastructure
locking/percpu-rwsem: Make percpu_free_rwsem() after kzalloc() safe
...
Pull wchan kernel address hiding from Ingo Molnar:
"This fixes a wchan related information leak in /proc/PID/stat.
There's a bit of an ABI twist to it: instead of setting the wchan
field to 0 (which is our usual technique) we set it conditionally to a
0/1 flag to keep ABI compatibility with older procps versions that
only fetches /proc/PID/wchan (symbolic names) if the absolute wchan
address is nonzero"
* 'core-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
fs/proc, core/debug: Don't expose absolute kernel addresses via wchan
Replace wait_event_killable with wait_event_interruptible
so that a program waiting for a posix lock can be
interrupted by a signal. With the killable version,
a program was not interruptible by a signal if it
had a signal handler set for it, overriding the default
action of terminating the process.
Signed-off-by: Eric Ren <zren@suse.com>
Signed-off-by: David Teigland <teigland@redhat.com>
Fix code comment about kmsg_dump register so it matches the code.
Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
It turns out that at least some versions of glibc end up reading
/proc/meminfo at every single startup, because glibc wants to know the
amount of memory the machine has. And while that's arguably insane,
it's just how things are.
And it turns out that it's not all that expensive most of the time, but
the vmalloc information statistics (amount of virtual memory used in the
vmalloc space, and the biggest remaining chunk) can be rather expensive
to compute.
The 'get_vmalloc_info()' function actually showed up on my profiles as
4% of the CPU usage of "make test" in the git source repository, because
the git tests are lots of very short-lived shell-scripts etc.
It turns out that apparently this same silly vmalloc info gathering
shows up on the facebook servers too, according to Dave Jones. So it's
not just "make test" for git.
We had two patches to just cache the information (one by me, one by
Ingo) to mitigate this issue, but the whole vmalloc information of of
rather dubious value to begin with, and people who *actually* want to
know what the situation is wrt the vmalloc area should just look at the
much more complete /proc/vmallocinfo instead.
In fact, according to my testing - and perhaps more importantly,
according to that big search engine in the sky: Google - there is
nothing out there that actually cares about those two expensive fields:
VmallocUsed and VmallocChunk.
So let's try to just remove them entirely. Actually, this just removes
the computation and reports the numbers as zero for now, just to try to
be minimally intrusive.
If this breaks anything, we'll obviously have to re-introduce the code
to compute this all and add the caching patches on top. But if given
the option, I'd really prefer to just remove this bad idea entirely
rather than add even more code to work around our historical mistake
that likely nobody really cares about.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge file descriptor allocation speedup.
Eric Dumazet has a test-case for a fairly common network deamon load
pattern: openign and closing a lot of sockets that each have very little
work done on them. It turns out that in that case, the cost of just
finding the correct file descriptor number can be a dominating factor.
We've long had a trivial optimization for allocating file descriptors
sequentially, but that optimization ends up being not very effective
when other file descriptors are being closed concurrently, and the fd
patterns are not some simple FIFO pattern. In such cases we ended up
spending a lot of time just scanning the bitmap of open file descriptors
in order to find the next file descriptor number to open.
This trivial patch-series mitigates that by simply introducing a
second-level bitmap of which words in the first bitmap are already fully
allocated. That cuts down the cost of scanning by an order of magnitude
in some pathological (but realistic) cases.
The second patch is an even more trivial patch to avoid unnecessarily
dirtying the cacheline for the close-on-exec bit array that normally
ends up being all empty.
* fs-file-descriptor-optimization:
vfs: conditionally clear close-on-exec flag
vfs: Fix pathological performance case for __alloc_fd()
We clear the close-on-exec flag when opening and closing files, and the
bit was almost always already clear before. Avoid dirtying the
cacheline if the clearning isn't necessary. That avoids unnecessary
cacheline dirtying and bouncing in multi-socket environments.
Eric Dumazet has a file descriptor benchmark that goes 4% faster from
this on his two-socket machine. It's probably partly superlinear
improvement due to getting slightly less spinlock contention on the
file_lock spinlock due to less work in the critical section.
Tested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Al Viro points out that:
> > * [Linux-specific aside] our __alloc_fd() can degrade quite badly
> > with some use patterns. The cacheline pingpong in the bitmap is probably
> > inevitable, unless we accept considerably heavier memory footprint,
> > but we also have a case when alloc_fd() takes O(n) and it's _not_ hard
> > to trigger - close(3);open(...); will have the next open() after that
> > scanning the entire in-use bitmap.
And Eric Dumazet has a somewhat realistic multithreaded microbenchmark
that opens and closes a lot of sockets with minimal work per socket.
This patch largely fixes it. We keep a 2nd-level bitmap of the open
file bitmaps, showing which words are already full. So then we can
traverse that second-level bitmap to efficiently skip already allocated
file descriptors.
On his benchmark, this improves performance by up to an order of
magnitude, by avoiding the excessive open file bitmap scanning.
Tested-and-acked-by: Eric Dumazet <edumazet@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull overlayfs bug fixes from Miklos Szeredi:
"This contains fixes for bugs that appeared in earlier kernels (all are
marked for -stable)"
* 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
ovl: free lower_mnt array in ovl_put_super
ovl: free stack of paths in ovl_fill_super
ovl: fix open in stacked overlay
ovl: fix dentry reference leak
ovl: use O_LARGEFILE in ovl_copy_up()
bdi_split_work_to_wbs() uses list_for_each_entry_rcu_continue()
to walk @bdi->wb_list. To set up the initial iteration
condition, it uses list_entry_rcu() to calculate the entry
pointer corresponding to the list head; however, this isn't an
actual RCU dereference and using list_entry_rcu() for it ended
up breaking a proposed list_entry_rcu() change because it was
feeding an non-lvalue pointer into the macro.
Don't use the RCU variant for simple pointer offsetting. Use
list_entry() instead.
Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Darren Hart <dvhart@linux.intel.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Dipankar Sarma <dipankar@in.ibm.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Patrick Marlier <patrick.marlier@gmail.com>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: pranith kumar <bobby.prani@gmail.com>
Link: http://lkml.kernel.org/r/20151027051939.GA19355@mtj.duckdns.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Attempting to hardlink to an unsafe file (e.g. a setuid binary) from
within an unprivileged user namespace fails, even if CAP_FOWNER is held
within the namespace. This may cause various failures, such as a gentoo
installation within a lxc container failing to build and install specific
packages.
This change permits hardlinking of files owned by mapped uids, if
CAP_FOWNER is held for that namespace. Furthermore, it improves consistency
by using the existing inode_owner_or_capable(), which is aware of
namespaced capabilities as of 23adbe12ef ("fs,userns: Change
inode_capable to capable_wrt_inode_uidgid").
Signed-off-by: Dirk Steinmetz <public@rsjtdrjgfuzkfg.com>
This is hitting us in Ubuntu during some dpkg upgrades in containers.
When upgrading a file dpkg creates a hard link to the old file to back
it up before overwriting it. When packages upgrade suid files owned by a
non-root user the link isn't permitted, and the package upgrade fails.
This patch fixes our problem.
Tested-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Pull block layer fixes from Jens Axboe:
"A final set of fixes for 4.3.
It is (again) bigger than I would have liked, but it's all been
through the testing mill and has been carefully reviewed by multiple
parties. Each fix is either a regression fix for this cycle, or is
marked stable. You can scold me at KS. The pull request contains:
- Three simple fixes for NVMe, fixing regressions since 4.3. From
Arnd, Christoph, and Keith.
- A single xen-blkfront fix from Cathy, fixing a NULL dereference if
an error is returned through the staste change callback.
- Fixup for some bad/sloppy code in nbd that got introduced earlier
in this cycle. From Markus Pargmann.
- A blk-mq tagset use-after-free fix from Junichi.
- A backing device lifetime fix from Tejun, fixing a crash.
- And finally, a set of regression/stable fixes for cgroup writeback
from Tejun"
* 'for-linus' of git://git.kernel.dk/linux-block:
writeback: remove broken rbtree_postorder_for_each_entry_safe() usage in cgwb_bdi_destroy()
NVMe: Fix memory leak on retried commands
block: don't release bdi while request_queue has live references
nvme: use an integer value to Linux errno values
blk-mq: fix use-after-free in blk_mq_free_tag_set()
nvme: fix 32-bit build warning
writeback: fix incorrect calculation of available memory for memcg domains
writeback: memcg dirty_throttle_control should be initialized with wb->memcg_completions
writeback: bdi_writeback iteration must not skip dying ones
writeback: fix bdi_writeback iteration in wakeup_dirtytime_writeback()
writeback: laptop_mode_timer_fn() needs rcu_read_lock() around bdi_writeback iteration
nbd: Add locking for tasks
xen-blkfront: check for null drvdata in blkback_changed (XenbusStateClosing)
