Highlights include:
Features:
- NFSv4.2 client support for hole punching and preallocation.
- Further RPC/RDMA client improvements.
- Add more RPC transport debugging tracepoints.
- Add RPC debugging tools in debugfs.
Bugfixes:
- Stable fix for layoutget error handling
- Fix a change in COMMIT behaviour resulting from the recent io code updates
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Merge tag 'nfs-for-3.19-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Highlights include:
Features:
- NFSv4.2 client support for hole punching and preallocation.
- Further RPC/RDMA client improvements.
- Add more RPC transport debugging tracepoints.
- Add RPC debugging tools in debugfs.
Bugfixes:
- Stable fix for layoutget error handling
- Fix a change in COMMIT behaviour resulting from the recent io code
updates"
* tag 'nfs-for-3.19-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (28 commits)
sunrpc: add a debugfs rpc_xprt directory with an info file in it
sunrpc: add debugfs file for displaying client rpc_task queue
nfs: Add DEALLOCATE support
nfs: Add ALLOCATE support
NFS: Clean up nfs4_init_callback()
NFS: SETCLIENTID XDR buffer sizes are incorrect
SUNRPC: serialize iostats updates
xprtrdma: Display async errors
xprtrdma: Enable pad optimization
xprtrdma: Re-write rpcrdma_flush_cqs()
xprtrdma: Refactor tasklet scheduling
xprtrdma: unmap all FMRs during transport disconnect
xprtrdma: Cap req_cqinit
xprtrdma: Return an errno from rpcrdma_register_external()
nfs: define nfs_inc_fscache_stats and using it as possible
nfs: replace nfs_add_stats with nfs_inc_stats when add one
NFS: Deletion of unnecessary checks before the function call "nfs_put_client"
sunrpc: eliminate RPC_TRACEPOINTS
sunrpc: eliminate RPC_DEBUG
lockd: eliminate LOCKD_DEBUG
...
Pull EFI updates from Ingo Molnar:
"Changes in this cycle are:
- support module unload for efivarfs (Mathias Krause)
- another attempt at moving x86 to libstub taking advantage of the
__pure attribute (Ard Biesheuvel)
- add EFI runtime services section to ptdump (Mathias Krause)"
* 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, ptdump: Add section for EFI runtime services
efi/x86: Move x86 back to libstub
efivarfs: Allow unloading when build as module
Pull x86 MPX support from Thomas Gleixner:
"This enables support for x86 MPX.
MPX is a new debug feature for bound checking in user space. It
requires kernel support to handle the bound tables and decode the
bound violating instruction in the trap handler"
* 'x86-mpx-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
asm-generic: Remove asm-generic arch_bprm_mm_init()
mm: Make arch_unmap()/bprm_mm_init() available to all architectures
x86: Cleanly separate use of asm-generic/mm_hooks.h
x86 mpx: Change return type of get_reg_offset()
fs: Do not include mpx.h in exec.c
x86, mpx: Add documentation on Intel MPX
x86, mpx: Cleanup unused bound tables
x86, mpx: On-demand kernel allocation of bounds tables
x86, mpx: Decode MPX instruction to get bound violation information
x86, mpx: Add MPX-specific mmap interface
x86, mpx: Introduce VM_MPX to indicate that a VMA is MPX specific
x86, mpx: Add MPX to disabled features
ia64: Sync struct siginfo with general version
mips: Sync struct siginfo with general version
mpx: Extend siginfo structure to include bound violation information
x86, mpx: Rename cfg_reg_u and status_reg
x86: mpx: Give bndX registers actual names
x86: Remove arbitrary instruction size limit in instruction decoder
Pull scheduler updates from Ingo Molnar:
"The main changes in this cycle are:
- 'Nested Sleep Debugging', activated when CONFIG_DEBUG_ATOMIC_SLEEP=y.
This instruments might_sleep() checks to catch places that nest
blocking primitives - such as mutex usage in a wait loop. Such
bugs can result in hard to debug races/hangs.
Another category of invalid nesting that this facility will detect
is the calling of blocking functions from within schedule() ->
sched_submit_work() -> blk_schedule_flush_plug().
There's some potential for false positives (if secondary blocking
primitives themselves are not ready yet for this facility), but the
kernel will warn once about such bugs per bootup, so the warning
isn't much of a nuisance.
This feature comes with a number of fixes, for problems uncovered
with it, so no messages are expected normally.
- Another round of sched/numa optimizations and refinements, for
CONFIG_NUMA_BALANCING=y.
- Another round of sched/dl fixes and refinements.
Plus various smaller fixes and cleanups"
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits)
sched: Add missing rcu protection to wake_up_all_idle_cpus
sched/deadline: Introduce start_hrtick_dl() for !CONFIG_SCHED_HRTICK
sched/numa: Init numa balancing fields of init_task
sched/deadline: Remove unnecessary definitions in cpudeadline.h
sched/cpupri: Remove unnecessary definitions in cpupri.h
sched/deadline: Fix rq->dl.pushable_tasks bug in push_dl_task()
sched/fair: Fix stale overloaded status in the busiest group finding logic
sched: Move p->nr_cpus_allowed check to select_task_rq()
sched/completion: Document when to use wait_for_completion_io_*()
sched: Update comments about CLONE_NEWUTS and CLONE_NEWIPC
sched/fair: Kill task_struct::numa_entry and numa_group::task_list
sched: Refactor task_struct to use numa_faults instead of numa_* pointers
sched/deadline: Don't check CONFIG_SMP in switched_from_dl()
sched/deadline: Reschedule from switched_from_dl() after a successful pull
sched/deadline: Push task away if the deadline is equal to curr during wakeup
sched/deadline: Add deadline rq status print
sched/deadline: Fix artificial overrun introduced by yield_task_dl()
sched/rt: Clean up check_preempt_equal_prio()
sched/core: Use dl_bw_of() under rcu_read_lock_sched()
sched: Check if we got a shallowest_idle_cpu before searching for least_loaded_cpu
...
a) don't bother with ->d_time for positives - we only check it for
negatives anyway.
b) make sure to set it at unlink and rmdir time - at *that* point
soon-to-be negative dentry matches then-current directory contents
c) don't go into renaming of old alias in vfat_lookup() unless it
has the same parent (which it will, unless we are seeing corrupted
image)
[hirofumi@mail.parknet.co.jp: make change minimum, don't call d_move() for dir]
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: <stable@vger.kernel.org> [3.17.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When we're enabling journal features, we cannot use the predicate
jbd2_journal_has_csum_v2or3() because we haven't yet set the sb
feature flag fields! Moreover, we just finished loading the shash
driver, so the test is unnecessary; calculate the seed always.
Without this patch, we fail to initialize the checksum seed the first
time we turn on journal_checksum, which means that all journal blocks
written during that first mount are corrupt. Transactions written
after the second mount will be fine, since the feature flag will be
set in the journal superblock. xfstests generic/{034,321,322} are the
regression tests.
(This is important for 3.18.)
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.coM>
Reported-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Don Bailey noticed that our page zeroing for compression at end-io time
isn't complete. This reworks a patch from Linus to push the zeroing
into the zlib and lzo specific functions instead of trying to handle the
corners inside btrfs_decompress_buf2page
Signed-off-by: Chris Mason <clm@fb.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Reported-by: Don A. Bailey <donb@securitymouse.com>
cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
These patches fixes for iostats and SETCLIENTID in addition to cleaning
up the nfs4_init_callback() function.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
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Merge tag 'nfs-cel-for-3.19' of git://git.linux-nfs.org/projects/anna/nfs-rdma into linux-next
Pull pull additional NFS client changes for 3.19 from Anna Schumaker:
"NFS: Generic client side changes from Chuck
These patches fixes for iostats and SETCLIENTID in addition to cleaning
up the nfs4_init_callback() function.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>"
* tag 'nfs-cel-for-3.19' of git://git.linux-nfs.org/projects/anna/nfs-rdma:
NFS: Clean up nfs4_init_callback()
NFS: SETCLIENTID XDR buffer sizes are incorrect
SUNRPC: serialize iostats updates
Pull nfsd bugfixes from Bruce Fields:
"These fix one mishandling of the case when security labels are
configured out, and two races in the 4.1 backchannel code"
* 'for-3.18' of git://linux-nfs.org/~bfields/linux:
nfsd: Fix slot wake up race in the nfsv4.1 callback code
SUNRPC: Fix locking around callback channel reply receive
nfsd: correctly define v4.2 support attributes
Pull aio fix from Ben LaHaise:
"Dirty page accounting fix for aio"
* git://git.kvack.org/~bcrl/aio-fixes:
aio: fix uncorrent dirty pages accouting when truncating AIO ring buffer
This patch adds support for using the NFS v4.2 operation DEALLOCATE to
punch holes in a file.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This patch adds support for using the NFS v4.2 operation ALLOCATE to
preallocate data in a file.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
nfs4_init_callback() is never invoked for NFS versions other than 4.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Use the correct calculation of the maximum size of a clientaddr4
when encoding and decoding SETCLIENTID operations. clientaddr4 is
defined in section 2.2.10 of RFC3530bis-31.
The usage in encode_setclientid_maxsz is missing the 4-byte length
in both strings, but is otherwise correct. decode_setclientid_maxsz
simply asks for a page of receive buffer space, which is
unnecessarily large (more than 4KB).
Note that a SETCLIENTID reply is either clientid+verifier, or
clientaddr4, depending on the returned NFS status. It doesn't
hurt to allocate enough space for both.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Define and use nfs_inc_fscache_stats when plus one, which can save to
pass one parameter.
Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The nfs_put_client() function tests whether its argument is NULL and then
returns immediately. Thus the test around the call is not needed.
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
LOCKD_DEBUG is always the same value as CONFIG_SUNRPC_DEBUG, so we can
just use it instead.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
nfs4_layoutget_release() drops layout hdr refcnt. Grab the refcnt
early so that it is safe to call .release in case nfs4_alloc_pages
fails.
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Fixes: a47970ff78 ("NFSv4.1: Hold reference to layout hdr in layoutget")
Cc: stable@vger.kernel.org # 3.9+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Recent work in the pgio layer made it possible for there to be more than one
request per page. This caused a subtle change in commit behavior, because
write.c:nfs_commit_unstable_pages compares the number of *pages* waiting for
writeback against the number of requests on a commit list to choose when to
send a COMMIT in a non-blocking flush.
This is probably hard to hit in normal operation - you have to be using
rsize/wsize < PAGE_SIZE, or pnfs with lots of boundaries that are not page
aligned to have a noticeable change in behavior.
Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Use the number of pages in the pagecache mapping instead of the
number of pnfs requests which is only slightly related.
Reported-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This should make the code easier to maintain in the future.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
NFS4ERR_ACCESS has number 13 and thus is matched and returned
immediately at the beginning of nfs4_map_errors() and there's no point
in checking it later.
Coverity-id: 733891
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Pull btrfs deadlock fix from Chris Mason:
"This has a fix for a long standing deadlock that we've been trying to
nail down for a while. It ended up being a bad interaction with the
fair reader/writer locks and the order btrfs reacquires locks in the
btree"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
btrfs: fix lockups from btrfs_clear_path_blocking
"The biggest change is to rename the filesystem from "overlayfs" to "overlay".
This will allow legacy overlayfs to be easily carried by distros alongside the
new mainline one. Also fix a couple of copy-up races and allow escaping comma
character in filenames."
The last bit is about commas in pathname mount options...
Check against !OVL_PATH_LOWER instead of OVL_PATH_MERGE. For a copied up
directory the two are currently equivalent.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Pass dentry into ovl_dir_read_merged() insted of upperpath and lowerpath.
This cleans up callers and paves the way for multi-layer directory reads.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Xattr operations can race with copy up. This does not matter as long as
we consistently fiter out "trunsted.overlay.opaque" attribute on upper
directories.
Previously we checked parent against OVL_PATH_MERGE. This is too general,
and prone to race with copy-up. I.e. we found the parent to be on the
lower layer but ovl_dentry_real() would return the copied-up dentry,
possibly with the "opaque" attribute.
So instead use ovl_path_real() and decide to filter the attributes based on
the actual type of the dentry we'll use.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
ovl_remove_and_whiteout() needs to check if upper dentry exists or not
after having locked upper parent directory.
Previously we used a "type" value computed before locking the upper parent
directory, which is susceptible to racing with copy-up.
There's a similar check in ovl_check_empty_and_clear(). This one is not
actually racy, since copy-up doesn't change the "emptyness" property of a
directory. Add a comment to this effect, and check the existence of upper
dentry locally to make the code cleaner.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Some distributions carry an "old" format of overlayfs while mainline has a
"new" format.
The distros will possibly want to keep the old overlayfs alongside the new
for compatibility reasons.
To make it possible to differentiate the two versions change the name of
the new one from "overlayfs" to "overlay".
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reported-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Cc: Andy Whitcroft <apw@canonical.com>
The currect code for nfsd41_cb_get_slot() and nfsd4_cb_done() has no
locking in order to guarantee atomicity, and so allows for races of
the form.
Task 1 Task 2
====== ======
if (test_and_set_bit(0) != 0) {
clear_bit(0)
rpc_wake_up_next(queue)
rpc_sleep_on(queue)
return false;
}
This patch breaks the race condition by adding a retest of the bit
after the call to rpc_sleep_on().
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The fair reader/writer locks mean that btrfs_clear_path_blocking needs
to strictly follow lock ordering rules even when we already have
blocking locks on a given path.
Before we can clear a blocking lock on the path, we need to make sure
all of the locks have been converted to blocking. This will remove lock
inversions against anyone spinning in write_lock() against the buffers
we're trying to get read locks on. These inversions didn't exist before
the fair read/writer locks, but now we need to be more careful.
We papered over this deadlock in the past by changing
btrfs_try_read_lock() to be a true trylock against both the spinlock and
the blocking lock. This was slower, and not sufficient to fix all the
deadlocks. This patch adds a btrfs_tree_read_lock_atomic(), which
basically means get the spinlock but trylock on the blocking lock.
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reported-by: Patrick Schmid <schmid@phys.ethz.ch>
cc: stable@vger.kernel.org #v3.15+
With the isofs_hash() function removed, isofs_hash_ms() is the only user
of isofs_hash_common(), but it's defined inside of an #ifdef, which triggers
this gcc warning in ARM axm55xx_defconfig starting with v3.18-rc3:
fs/isofs/inode.c:177:1: warning: 'isofs_hash_common' defined but not used [-Wunused-function]
This patch moves the function inside of the same #ifdef section to avoid that
warning, which seems the best compromise of a relatively harmless patch for
a late -rc.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: b0afd8e5db ("isofs: don't bother with ->d_op for normal case")
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
In "d_prune_alias(): just lock the parent and call __dentry_kill()" the old
dget + d_drop + dput has been replaced with lock_parent + __dentry_kill;
unfortunately, dput() does more than just killing dentry - it also drops the
reference to parent. New variant leaks that reference and needs dput(parent)
after killing the child off.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Even when security labels are disabled we support at least the same
attributes as v4.1.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: stable@kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We no longer need mpx.h in exec.c. This will obviously also
break the build for non-x86 builds. We get the MPX includes that
we need from mmu_context.h now.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Hansen <dave@sr71.net>
Link: http://lkml.kernel.org/r/20141118003608.837015B3@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This is really the meat of the MPX patch set. If there is one patch to
review in the entire series, this is the one. There is a new ABI here
and this kernel code also interacts with userspace memory in a
relatively unusual manner. (small FAQ below).
Long Description:
This patch adds two prctl() commands to provide enable or disable the
management of bounds tables in kernel, including on-demand kernel
allocation (See the patch "on-demand kernel allocation of bounds tables")
and cleanup (See the patch "cleanup unused bound tables"). Applications
do not strictly need the kernel to manage bounds tables and we expect
some applications to use MPX without taking advantage of this kernel
support. This means the kernel can not simply infer whether an application
needs bounds table management from the MPX registers. The prctl() is an
explicit signal from userspace.
PR_MPX_ENABLE_MANAGEMENT is meant to be a signal from userspace to
require kernel's help in managing bounds tables.
PR_MPX_DISABLE_MANAGEMENT is the opposite, meaning that userspace don't
want kernel's help any more. With PR_MPX_DISABLE_MANAGEMENT, the kernel
won't allocate and free bounds tables even if the CPU supports MPX.
PR_MPX_ENABLE_MANAGEMENT will fetch the base address of the bounds
directory out of a userspace register (bndcfgu) and then cache it into
a new field (->bd_addr) in the 'mm_struct'. PR_MPX_DISABLE_MANAGEMENT
will set "bd_addr" to an invalid address. Using this scheme, we can
use "bd_addr" to determine whether the management of bounds tables in
kernel is enabled.
Also, the only way to access that bndcfgu register is via an xsaves,
which can be expensive. Caching "bd_addr" like this also helps reduce
the cost of those xsaves when doing table cleanup at munmap() time.
Unfortunately, we can not apply this optimization to #BR fault time
because we need an xsave to get the value of BNDSTATUS.
==== Why does the hardware even have these Bounds Tables? ====
MPX only has 4 hardware registers for storing bounds information.
If MPX-enabled code needs more than these 4 registers, it needs to
spill them somewhere. It has two special instructions for this
which allow the bounds to be moved between the bounds registers
and some new "bounds tables".
They are similar conceptually to a page fault and will be raised by
the MPX hardware during both bounds violations or when the tables
are not present. This patch handles those #BR exceptions for
not-present tables by carving the space out of the normal processes
address space (essentially calling the new mmap() interface indroduced
earlier in this patch set.) and then pointing the bounds-directory
over to it.
The tables *need* to be accessed and controlled by userspace because
the instructions for moving bounds in and out of them are extremely
frequent. They potentially happen every time a register pointing to
memory is dereferenced. Any direct kernel involvement (like a syscall)
to access the tables would obviously destroy performance.
==== Why not do this in userspace? ====
This patch is obviously doing this allocation in the kernel.
However, MPX does not strictly *require* anything in the kernel.
It can theoretically be done completely from userspace. Here are
a few ways this *could* be done. I don't think any of them are
practical in the real-world, but here they are.
Q: Can virtual space simply be reserved for the bounds tables so
that we never have to allocate them?
A: As noted earlier, these tables are *HUGE*. An X-GB virtual
area needs 4*X GB of virtual space, plus 2GB for the bounds
directory. If we were to preallocate them for the 128TB of
user virtual address space, we would need to reserve 512TB+2GB,
which is larger than the entire virtual address space today.
This means they can not be reserved ahead of time. Also, a
single process's pre-popualated bounds directory consumes 2GB
of virtual *AND* physical memory. IOW, it's completely
infeasible to prepopulate bounds directories.
Q: Can we preallocate bounds table space at the same time memory
is allocated which might contain pointers that might eventually
need bounds tables?
A: This would work if we could hook the site of each and every
memory allocation syscall. This can be done for small,
constrained applications. But, it isn't practical at a larger
scale since a given app has no way of controlling how all the
parts of the app might allocate memory (think libraries). The
kernel is really the only place to intercept these calls.
Q: Could a bounds fault be handed to userspace and the tables
allocated there in a signal handler instead of in the kernel?
A: (thanks to tglx) mmap() is not on the list of safe async
handler functions and even if mmap() would work it still
requires locking or nasty tricks to keep track of the
allocation state there.
Having ruled out all of the userspace-only approaches for managing
bounds tables that we could think of, we create them on demand in
the kernel.
Based-on-patch-by: Qiaowei Ren <qiaowei.ren@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: linux-mm@kvack.org
Cc: linux-mips@linux-mips.org
Cc: Dave Hansen <dave@sr71.net>
Link: http://lkml.kernel.org/r/20141114151829.AD4310DE@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
MPX-enabled applications using large swaths of memory can
potentially have large numbers of bounds tables in process
address space to save bounds information. These tables can take
up huge swaths of memory (as much as 80% of the memory on the
system) even if we clean them up aggressively. In the worst-case
scenario, the tables can be 4x the size of the data structure
being tracked. IOW, a 1-page structure can require 4 bounds-table
pages.
Being this huge, our expectation is that folks using MPX are
going to be keen on figuring out how much memory is being
dedicated to it. So we need a way to track memory use for MPX.
If we want to specifically track MPX VMAs we need to be able to
distinguish them from normal VMAs, and keep them from getting
merged with normal VMAs. A new VM_ flag set only on MPX VMAs does
both of those things. With this flag, MPX bounds-table VMAs can
be distinguished from other VMAs, and userspace can also walk
/proc/$pid/smaps to get memory usage for MPX.
In addition to this flag, we also introduce a special ->vm_ops
specific to MPX VMAs (see the patch "add MPX specific mmap
interface"), but currently different ->vm_ops do not by
themselves prevent VMA merging, so we still need this flag.
We understand that VM_ flags are scarce and are open to other
options.
Signed-off-by: Qiaowei Ren <qiaowei.ren@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: linux-mm@kvack.org
Cc: linux-mips@linux-mips.org
Cc: Dave Hansen <dave@sr71.net>
Link: http://lkml.kernel.org/r/20141114151825.565625B3@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* Another attempt at moving x86 to libstub taking advantage of the
__pure attribute - Ard Biesheuvel
* Add EFI runtime services section to ptdump - Mathias Krause
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Merge tag 'efi-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into x86/efi
Pull EFI updates for v3.19 from Matt Fleming:
- Support module unload for efivarfs - Mathias Krause
- Another attempt at moving x86 to libstub taking advantage of the
__pure attribute - Ard Biesheuvel
- Add EFI runtime services section to ptdump - Mathias Krause
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Highlights include:
- Stable patches to fix NFSv4.x delegation reclaim error paths
- Fix a bug whereby we were advertising NFSv4.1 but using NFSv4.2 features
- Fix a use-after-free problem with pNFS block layouts
- Fix a memory leak in the pNFS files O_DIRECT code
- Replace an intrusive and Oops-prone performance fix in the NFSv4 atomic
open code with a safer one-line version and revert the two original patches.
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Merge tag 'nfs-for-3.18-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client bugfixes from Trond Myklebust:
"Highlights include:
- stable patches to fix NFSv4.x delegation reclaim error paths
- fix a bug whereby we were advertising NFSv4.1 but using NFSv4.2
features
- fix a use-after-free problem with pNFS block layouts
- fix a memory leak in the pNFS files O_DIRECT code
- replace an intrusive and Oops-prone performance fix in the NFSv4
atomic open code with a safer one-line version and revert the two
original patches"
* tag 'nfs-for-3.18-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
sunrpc: fix sleeping under rcu_read_lock in gss_stringify_acceptor
NFS: Don't try to reclaim delegation open state if recovery failed
NFSv4: Ensure that we call FREE_STATEID when NFSv4.x stateids are revoked
NFSv4: Fix races between nfs_remove_bad_delegation() and delegation return
NFSv4.1: nfs41_clear_delegation_stateid shouldn't trust NFS_DELEGATED_STATE
NFSv4: Ensure that we remove NFSv4.0 delegations when state has expired
NFS: SEEK is an NFS v4.2 feature
nfs: Fix use of uninitialized variable in nfs_getattr()
nfs: Remove bogus assignment
nfs: remove spurious WARN_ON_ONCE in write path
pnfs/blocklayout: serialize GETDEVICEINFO calls
nfs: fix pnfs direct write memory leak
Revert "NFS: nfs4_do_open should add negative results to the dcache."
Revert "NFS: remove BUG possibility in nfs4_open_and_get_state"
NFSv4: Ensure nfs_atomic_open set the dentry verifier on ENOENT
Merge misc fixes from Andrew Morton:
"15 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
MAINTAINERS: add IIO include files
kernel/panic.c: update comments for print_tainted
mem-hotplug: reset node present pages when hot-adding a new pgdat
mem-hotplug: reset node managed pages when hot-adding a new pgdat
mm/debug-pagealloc: correct freepage accounting and order resetting
fanotify: fix notification of groups with inode & mount marks
mm, compaction: prevent infinite loop in compact_zone
mm: alloc_contig_range: demote pages busy message from warn to info
mm/slab: fix unalignment problem on Malta with EVA due to slab merge
mm/page_alloc: restrict max order of merging on isolated pageblock
mm/page_alloc: move freepage counting logic to __free_one_page()
mm/page_alloc: add freepage on isolate pageblock to correct buddy list
mm/page_alloc: fix incorrect isolation behavior by rechecking migratetype
mm/compaction: skip the range until proper target pageblock is met
zram: avoid kunmap_atomic() of a NULL pointer
fsnotify() needs to merge inode and mount marks lists when notifying
groups about events so that ignore masks from inode marks are reflected
in mount mark notifications and groups are notified in proper order
(according to priorities).
Currently the sorting of the lists done by fsnotify_add_inode_mark() /
fsnotify_add_vfsmount_mark() and fsnotify() differed which resulted
ignore masks not being used in some cases.
Fix the problem by always using the same comparison function when
sorting / merging the mark lists.
Thanks to Heinrich Schuchardt for improvements of my patch.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=87721
Signed-off-by: Jan Kara <jack@suse.cz>
Reported-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Tested-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
TID of cap flush ack is 64 bits, but ceph_inode_info::flushing_cap_tid
is only 16 bits. 16 bits should be plenty to let the cap flush updates
pipeline appropriately, but we need to cast in the proper direction when
comparing these differently-sized versions. So downcast the 64-bits one
to 16 bits.
Reflects ceph.git commit a5184cf46a6e867287e24aeb731634828467cd98.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
Reviewed-by: Ilya Dryomov <idryomov@redhat.com>
Any attempt to call nfs_remove_bad_delegation() while a delegation is being
returned is currently a no-op. This means that we can end up looping
forever in nfs_end_delegation_return() if something causes the delegation
to be revoked.
This patch adds a mechanism whereby the state recovery code can communicate
to the delegation return code that the delegation is no longer valid and
that it should not be used when reclaiming state.
It also changes the return value for nfs4_handle_delegation_recall_error()
to ensure that nfs_end_delegation_return() does not reattempt the lock
reclaim before state recovery is done.
http://lkml.kernel.org/r/CAN-5tyHwG=Cn2Q9KsHWadewjpTTy_K26ee+UnSvHvG4192p-Xw@mail.gmail.com
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
