Commit Graph

616116 Commits

Author SHA1 Message Date
Linus Torvalds
755b20f492 Metag architecture changes for v4.8
Just a few minor fixes:
 - Fix another incorrect inline asm register constraint, which has been
   lying quietly for 5 and a half years before finally causing build
   breakage during this merge window.
 - Removal of duplicated KERN_INFO from Joe Perches.
 - Typo fixes from Andrea Gelmini.
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Merge tag 'metag-for-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/metag

Pull metag architecture updates from James Hogan:
 "Just a few minor fixes:

   - Fix another incorrect inline asm register constraint, which has
     been lying quietly for 5 and a half years before finally causing
     build breakage during this merge window.

   - Removal of duplicated KERN_INFO from Joe Perches

   - Typo fixes from Andrea Gelmini"

* tag 'metag-for-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/metag:
  metag: Fix __cmpxchg_u32 asm constraint for CMP
  metag: Remove duplicate KERN_<LEVEL> prefix
  metag: Fix typos
2016-08-05 08:58:00 -04:00
Rich Felker
e61c10e468 sh: add device tree source for J2 FPGA on Mimas v2 board
Signed-off-by: Rich Felker <dalias@libc.org>
2016-08-05 03:38:26 +00:00
Rich Felker
c8e67a850b sh: add defconfig for J-Core J2
This defconfig is intended not to be specific to a particular board;
it enables drivers for all currently-supported hardware, and should be
updated to include additional drivers as they are added.

Signed-off-by: Rich Felker <dalias@libc.org>
2016-08-05 03:38:22 +00:00
Rich Felker
15f0c8f2f3 sh: use common clock framework with device tree boards
Enable common clk framework for DT-based boards and disable code that
depends on the legacy sh clk framework when common clk is enabled.
Once legacy drivers are converted over, the old code can be removed
entirely.

Signed-off-by: Rich Felker <dalias@libc.org>
2016-08-05 03:29:45 +00:00
Yoshinori Sato
74bdaa611f sh: system call wire up
Signed-off-by: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Rich Felker <dalias@libc.org>
2016-08-05 03:29:44 +00:00
Markus Elfring
a316399635 sh: Delete unnecessary checks before the function call "mempool_destroy"
The mempool_destroy() function tests whether its argument is NULL
and then returns immediately. Thus the test around the calls is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Rich Felker <dalias@libc.org>
2016-08-05 03:29:42 +00:00
Rich Felker
a1e262f6f1 sh: do not perform IPI-based cache flush except on boards that need it
Signed-off-by: Rich Felker <dalias@libc.org>
2016-08-05 03:29:40 +00:00
Rich Felker
b4214e41b7 sh: add SMP support for J2
Support is hooked up via a cpu start method specified in the device
tree, and also depends on DT nodes that describe the interfaces for
performing IPI and identifying which cpu execution is taking place on.
The currently used method is a form of spin table, where secondary
cpus are unblocked by writing to a special address.

Signed-off-by: Rich Felker <dalias@libc.org>
2016-08-05 03:29:39 +00:00
Rich Felker
4b6ef05b3e sh: SMP support for SH2 entry.S
The SH2 version of entry.S uses global variables, which need to be
cpu-local in order to work with SMP. For ease of access from asm,
simply use arrays indexed by cpu number, and require the availability
of an address (mmio register or properly setup per-cpu memory) from
which the current cpu's index can be read.

Signed-off-by: Rich Felker <dalias@libc.org>
2016-08-05 03:29:37 +00:00
Rich Felker
00b73d8d1b sh: add working futex atomic ops on userspace addresses for smp
The version of futex.h in asm-generic should really be adapted to do
the same thing so that this hideous code does not have to be
duplicated per-arch.

Signed-off-by: Rich Felker <dalias@libc.org>
2016-08-05 03:29:36 +00:00
Rich Felker
2b47d54ed4 sh: add J2 atomics using the cas.l instruction
Signed-off-by: Rich Felker <dalias@libc.org>
2016-08-05 03:29:34 +00:00
Rich Felker
834da19705 sh: add AT_HWCAP flag for J-Core cas.l instruction
The J-Core cpu has, as an ISA extension, an atomic compare-and-swap
instruction cas.l which applications need to use (instead the imask or
gusa atomic models, which are fundamentally limited to UP) for
synchronization in order to be compatible with SMP systems. Provide a
hwcap flag so that it's possible to do runtime selection and support
both.

Signed-off-by: Rich Felker <dalias@libc.org>
2016-08-05 03:29:32 +00:00
Rich Felker
5a846abad0 sh: add support for J-Core J2 processor
At the CPU/ISA level, the J2 is compatible with SH-2, and thus the
changes to add J2 support build on existing SH-2 support. However, J2
does not duplicate the memory-mapped SH-2 features like the cache
interface. Instead, the cache interfaces is described in the device
tree, and new code is added to be able to access the flat device tree
at early boot before it is unflattened.

Support is also added for receiving interrupts on trap numbers in the
range 16 to 31, since the J-Core aic1 interrupt controller generates
these traps. This range was unused but nominally for hardware
exceptions on SH-2, and a few values in this range were used for
exceptions on SH-2A, but SH-2A has its own version of the relevant
code.

No individual cpu subtypes are added for J2 since the intent moving
forward is to represent SoCs with device tree rather than as
hard-coded subtypes in the kernel. The CPU_SUBTYPE_J2 Kconfig item
exists only to fit into the existing cpu selection mechanism until it
is overhauled.

Signed-off-by: Rich Felker <dalias@libc.org>
2016-08-05 03:29:31 +00:00
Rafael J. Wysocki
dd7fd3a82c ACPI / hotplug / PCI: Runtime resume bridges before bus rescans
If a PCI bridge (or PCIe port) that is runtime-suspended gets an ACPI
hotplug notification, such as a bus check, it has to be resumed before
re-scanning the devices below it, or those devices will not be
accessible and will be treated as hot-removed.

Make that happen and let the bridge suspend again after the bus below it
has been re-scanned.

This is a replacement for commit 16468c783c ("ACPI / hotplug / PCI:
Runtime resume bridge before rescan") that has been reverted, because it
introduced a system resume regression (due to missing bridge->pci_dev
checks that are necessary in case the notification is targeted at the
host bridge) and it is necessary for the code added by commit
006d44e49a ("PCI: Add runtime PM support for PCIe ports") to work as
expected.

Tested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-04 21:33:58 -04:00
Joe Perches
5055610e3d .mailmap: Correct entries for Mauro Carvalho Chehab and Shuah Khan
mailmap entries may not use more than 2 email addresses per line.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-08-04 21:35:41 -03:00
Linus Torvalds
f8fbd8c49b Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
 "A few late-breaking fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm/memblock.c: fix NULL dereference error
  MAINTAINERS: update cgroup's document path
  slub: drop bogus inline for fixup_red_left()
  powerpc/fsl_rio: fix a missing error code
  mm: initialise per_cpu_nodestats for all online pgdats at boot
  mm/memblock: fix a typo in a comment
  mm: disable CONFIG_MEMORY_HOTPLUG when KASAN is enabled
2016-08-04 20:31:20 -04:00
Linus Torvalds
84e39eeb08 Second round of merge items for 4.8
- hfi1 driver updates
 - Fix for max SGEs allowed via RDMA R/W API
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Merge tag 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma

Pull second round of rdma updates from Doug Ledford:
 "This can be split out into just two categories:

   - fixes to the RDMA R/W API in regards to SG list length limits
     (about 5 patches)

   - fixes/features for the Intel hfi1 driver (everything else)

  The hfi1 driver is still being brought to full feature support by
  Intel, and they have a lot of people working on it, so that amounts to
  almost the entirety of this pull request"

* tag 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma: (84 commits)
  IB/hfi1: Add cache evict LRU list
  IB/hfi1: Fix memory leak during unexpected shutdown
  IB/hfi1: Remove unneeded mm argument in remove function
  IB/hfi1: Consistently call ops->remove outside spinlock
  IB/hfi1: Use evict mmu rb operation
  IB/hfi1: Add evict operation to the mmu rb handler
  IB/hfi1: Fix TID caching actions
  IB/hfi1: Make the cache handler own its rb tree root
  IB/hfi1: Make use of mm consistent
  IB/hfi1: Fix user SDMA racy user request claim
  IB/hfi1: Fix error condition that needs to clean up
  IB/hfi1: Release node on insert failure
  IB/hfi1: Validate SDMA user iovector count
  IB/hfi1: Validate SDMA user request index
  IB/hfi1: Use the same capability state for all shared contexts
  IB/hfi1: Prevent null pointer dereference
  IB/hfi1: Rename TID mmu_rb_* functions
  IB/hfi1: Remove unneeded empty check in hfi1_mmu_rb_unregister()
  IB/hfi1: Restructure hfi1_file_open
  IB/hfi1: Make iovec loop index easy to understand
  ...
2016-08-04 20:26:31 -04:00
Linus Torvalds
0cda611386 Round one of 4.8 code
- Updates/fixes for iw_cxgb4 driver
 - Updates/fixes for mlx5 driver
 - Add flow steering and RSS API
 - Add hardware stats to mlx4 and mlx5 drivers
 - Add firmware version API for RDMA driver use
 - Add the rxe driver (this is a software RoCE driver that makes any
   Ethernet device a RoCE device)
 - Fixes for i40iw driver
 - Support for send only multicast joins in the cma layer
 - Other minor fixes
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma

Pull base rdma updates from Doug Ledford:
 "Round one of 4.8 code: while this is mostly normal, there is a new
  driver in here (the driver was hosted outside the kernel for several
  years and is actually a fairly mature and well coded driver).  It
  amounts to 13,000 of the 16,000 lines of added code in here.

  Summary:

   - Updates/fixes for iw_cxgb4 driver
   - Updates/fixes for mlx5 driver
   - Add flow steering and RSS API
   - Add hardware stats to mlx4 and mlx5 drivers
   - Add firmware version API for RDMA driver use
   - Add the rxe driver (this is a software RoCE driver that makes any
     Ethernet device a RoCE device)
   - Fixes for i40iw driver
   - Support for send only multicast joins in the cma layer
   - Other minor fixes"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma: (72 commits)
  Soft RoCE driver
  IB/core: Support for CMA multicast join flags
  IB/sa: Add cached attribute containing SM information to SA port
  IB/uverbs: Fix race between uverbs_close and remove_one
  IB/mthca: Clean up error unwind flow in mthca_reset()
  IB/mthca: NULL arg to pci_dev_put is OK
  IB/hfi1: NULL arg to sc_return_credits is OK
  IB/mlx4: Add diagnostic hardware counters
  net/mlx4: Query performance and diagnostics counters
  net/mlx4: Add diagnostic counters capability bit
  Use smaller 512 byte messages for portmapper messages
  IB/ipoib: Report SG feature regardless of HW UD CSUM capability
  IB/mlx4: Don't use GFP_ATOMIC for CQ resize struct
  IB/hfi1: Disable by default
  IB/rdmavt: Disable by default
  IB/mlx5: Fix port counter ID association to QP offset
  IB/mlx5: Fix iteration overrun in GSI qps
  i40iw: Add NULL check for puda buffer
  i40iw: Change dup_ack_thresh to u8
  i40iw: Remove unnecessary check for moving CQ head
  ...
2016-08-04 20:10:31 -04:00
Linus Torvalds
fdf1f7ff1b Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
Pull SCSI target updates from Nicholas Bellinger:
 "The most notable item is IBM virtual SCSI target driver, that was
  originally ported to target-core back in 2010 by Tomo-san, and has
  been brought forward to v4.x code by Bryant Ly, Michael Cyr and co
  over the last months.

  Also included are two ORDERED task related bug-fixes Bryant + Michael
  found along the way using ibmvscsis with AIX guests, plus a few
  miscellaneous target-core + iscsi-target bug-fixes with associated
  stable tags"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
  target: fix spelling mistake: "limitiation" -> "limitation"
  target: Fix residual overflow handling in target_complete_cmd_with_length
  tcm_fc: set and unset FCP_SPPF_TARG_FCN
  iscsi-target: Fix panic when adding second TCP connection to iSCSI session
  ibmvscsis: Initial commit of IBM VSCSI Tgt Driver
  target: Fix ordered task CHECK_CONDITION early exception handling
  target: Fix ordered task target_setup_cmd_from_cdb exception hang
  target: Fix max_unmap_lba_count calc overflow
  target: Fix race between iscsi-target connection shutdown + ABORT_TASK
  target: Fix missing complete during ABORT_TASK + CMD_T_FABRIC_STOP
2016-08-04 20:04:37 -04:00
zijun_hu
e47608ab6d mm/memblock.c: fix NULL dereference error
It causes NULL dereference error and failure to get type_a->regions[0]
info if parameter type_b of __next_mem_range_rev() == NULL

Fix this by checking before dereferring and initializing idx_b to 0

The approach is tested by dumping all types of region via
__memblock_dump_all() and __next_mem_range_rev() fixed to UART
separately the result is okay after checking the logs.

Link: http://lkml.kernel.org/r/57A0320D.6070102@zoho.com
Signed-off-by: zijun_hu <zijun_hu@htc.com>
Tested-by: zijun_hu <zijun_hu@htc.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-04 20:02:09 -04:00
seokhoon.yoon
4b16b0c0bf MAINTAINERS: update cgroup's document path
cgroup's document path is changed to "cgroup-v1".  update it.

Link: http://lkml.kernel.org/r/1470322507-5161-1-git-send-email-iamyooon@gmail.com
Signed-off-by: seokhoon.yoon <iamyooon@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-04 20:02:09 -04:00
Geert Uytterhoeven
117d54df7a slub: drop bogus inline for fixup_red_left()
With m68k-linux-gnu-gcc-4.1:

    include/linux/slub_def.h:126: warning: `fixup_red_left' declared inline after being called
    include/linux/slub_def.h:126: warning: previous declaration of `fixup_red_left' was here

Commit c146a2b98e ("mm, kasan: account for object redzone in SLUB's
nearest_obj()") made fixup_red_left() global, but forgot to remove the
inline keyword.

Fixes: c146a2b98e ("mm, kasan: account for object redzone in SLUB's nearest_obj()")
Link: http://lkml.kernel.org/r/1470256262-1586-1-git-send-email-geert@linux-m68k.org
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Alexander Potapenko <glider@google.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>
2016-08-04 20:02:09 -04:00
Dan Carpenter
380afa3698 powerpc/fsl_rio: fix a missing error code
We should set the error code here rather than incorrectly returning 0.
Otherwise static checkers complain.

Link: http://lkml.kernel.org/r/20160804053525.GM775@mwanda
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Alexandre Bounine <alexandre.bounine@idt.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-04 20:02:09 -04:00
Mel Gorman
b4911ea2bc mm: initialise per_cpu_nodestats for all online pgdats at boot
Paul Mackerras and Reza Arbab reported that machines with memoryless
nodes fail when vmstats are refreshed.  Paul reported an oops as follows

  Unable to handle kernel paging request for data at address 0xff7a10000
  Faulting instruction address: 0xc000000000270cd0
  Oops: Kernel access of bad area, sig: 11 [#1]
  SMP NR_CPUS=2048 NUMA PowerNV
  Modules linked in:
  CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.7.0-kvm+ #118
  task: c000000ff0680010 task.stack: c000000ff0704000
  NIP: c000000000270cd0 LR: c000000000270ce8 CTR: 0000000000000000
  REGS: c000000ff0707900 TRAP: 0300   Not tainted  (4.7.0-kvm+)
  MSR: 9000000102009033 <SF,HV,VEC,EE,ME,IR,DR,RI,LE,TM[E]>  CR: 846b6824  XER: 20000000
  CFAR: c000000000008768 DAR: 0000000ff7a10000 DSISR: 42000000 SOFTE: 1
  NIP refresh_zone_stat_thresholds+0x80/0x240
  LR refresh_zone_stat_thresholds+0x98/0x240
  Call Trace:
    refresh_zone_stat_thresholds+0xb8/0x240 (unreliable)

Both supplied potential fixes but one potentially misses checks and
another had redundant initialisations.  This version initialises
per_cpu_nodestats on a per-pgdat basis instead of on a per-zone basis.

Link: http://lkml.kernel.org/r/20160804092404.GI2799@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Reported-by: Paul Mackerras <paulus@ozlabs.org>
Reported-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Tested-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-04 20:02:09 -04:00
Alexander Kuleshov
412d0008d6 mm/memblock: fix a typo in a comment
s/accomodate/accommodate/

Link: http://lkml.kernel.org/r/20160804121824.18100-1-kuleshovmail@gmail.com
Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-04 20:02:09 -04:00
zhong jiang
1e185736d2 mm: disable CONFIG_MEMORY_HOTPLUG when KASAN is enabled
At present it is obvious that memory online and offline will fail when
KASAN is enabled.  So add the condition to limit the memory_hotplug when
KASAN is enabled.

Link: http://lkml.kernel.org/r/1470063651-29519-1-git-send-email-zhongjiang@huawei.com
Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-04 20:02:09 -04:00
Linus Torvalds
a71e36045e Highlights:
Trond made a change to the server's tcp logic that allows a fast
 	client to better take advantage of high bandwidth networks, but
 	may increase the risk that a single client could starve other
 	clients; a new sunrpc.svc_rpc_per_connection_limit parameter
 	should help mitigate this in the (hopefully unlikely) event this
 	becomes a problem in practice.
 
 	Tom Haynes added a minimal flex-layout pnfs server, which is of
 	no use in production for now--don't build it unless you're doing
 	client testing or further server development.
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Merge tag 'nfsd-4.8' of git://linux-nfs.org/~bfields/linux

Pull nfsd updates from Bruce Fields:
 "Highlights:

   - Trond made a change to the server's tcp logic that allows a fast
     client to better take advantage of high bandwidth networks, but may
     increase the risk that a single client could starve other clients;
     a new sunrpc.svc_rpc_per_connection_limit parameter should help
     mitigate this in the (hopefully unlikely) event this becomes a
     problem in practice.

   - Tom Haynes added a minimal flex-layout pnfs server, which is of no
     use in production for now--don't build it unless you're doing
     client testing or further server development"

* tag 'nfsd-4.8' of git://linux-nfs.org/~bfields/linux: (32 commits)
  nfsd: remove some dead code in nfsd_create_locked()
  nfsd: drop unnecessary MAY_EXEC check from create
  nfsd: clean up bad-type check in nfsd_create_locked
  nfsd: remove unnecessary positive-dentry check
  nfsd: reorganize nfsd_create
  nfsd: check d_can_lookup in fh_verify of directories
  nfsd: remove redundant zero-length check from create
  nfsd: Make creates return EEXIST instead of EACCES
  SUNRPC: Detect immediate closure of accepted sockets
  SUNRPC: accept() may return sockets that are still in SYN_RECV
  nfsd: allow nfsd to advertise multiple layout types
  nfsd: Close race between nfsd4_release_lockowner and nfsd4_lock
  nfsd/blocklayout: Make sure calculate signature/designator length aligned
  xfs: abstract block export operations from nfsd layouts
  SUNRPC: Remove unused callback xpo_adjust_wspace()
  SUNRPC: Change TCP socket space reservation
  SUNRPC: Add a server side per-connection limit
  SUNRPC: Micro optimisation for svc_data_ready
  SUNRPC: Call the default socket callbacks instead of open coding
  SUNRPC: lock the socket while detaching it
  ...
2016-08-04 19:59:06 -04:00
Linus Torvalds
d58b0d980f Merge branch 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull more btrfs updates from Chris Mason:
 "This is part two of my btrfs pull, which is some cleanups and a batch
  of fixes.

  Most of the code here is from Jeff Mahoney, making the pointers we
  pass around internally more consistent and less confusing overall.  I
  noticed a small problem right before I sent this out yesterday, so I
  fixed it up and re-tested overnight"

* 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (40 commits)
  Btrfs: fix __MAX_CSUM_ITEMS
  btrfs: btrfs_abort_transaction, drop root parameter
  btrfs: add btrfs_trans_handle->fs_info pointer
  btrfs: btrfs_relocate_chunk pass extent_root to btrfs_end_transaction
  btrfs: convert nodesize macros to static inlines
  btrfs: introduce BTRFS_MAX_ITEM_SIZE
  btrfs: cleanup, remove prototype for btrfs_find_root_ref
  btrfs: copy_to_sk drop unused root parameter
  btrfs: simpilify btrfs_subvol_inherit_props
  btrfs: tests, use BTRFS_FS_STATE_DUMMY_FS_INFO instead of dummy root
  btrfs: tests, require fs_info for root
  btrfs: tests, move initialization into tests/
  btrfs: btrfs_test_opt and friends should take a btrfs_fs_info
  btrfs: prefix fsid to all trace events
  btrfs: plumb fs_info into btrfs_work
  btrfs: remove obsolete part of comment in statfs
  btrfs: hide test-only member under ifdef
  btrfs: Ratelimit "no csum found" info message
  btrfs: Add ratelimit to btrfs printing
  Btrfs: fix unexpected balance crash due to BUG_ON
  ...
2016-08-04 19:56:16 -04:00
Linus Torvalds
3a303258ef This pull request contains mostly cleanups and minor
improvements of UBI and UBIFS.
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Merge tag 'upstream-4.8-rc1' of git://git.infradead.org/linux-ubifs

Pull UBI/UBIFS updates from Richard Weinberger:
 "This contains mostly cleanups and minor improvements of UBI and UBIFS"

* tag 'upstream-4.8-rc1' of git://git.infradead.org/linux-ubifs:
  ubi: Use bitmaps in Fastmap self-check code
  ubi: Be more paranoid while seaching for the most recent Fastmap
  ubi: Check whether the Fastmap anchor matches the super block
  ubi: Rework Fastmap attach base code
  ubi: Fix whitespace issue in count_fastmap_pebs()
  ubi: Introduce vol_ignored()
  ubi: Fix scan_fast() comment
  ubifs: switch_gc_head: Remove redondant sync of wbuf
  ubi: Make volume resize power cut aware
  ubi: Fix early logging
  ubi: gluebi: Fix double refcounting
  ubifs: Silence early error messages if MS_SILENT is set
  ubi: Fix race condition between ubi device creation and udev
  ubifs: Update comment for ubifs_errc
  ubi: Only read necessary size when reading the VID header
  ubifs: Make xattr structures static
  ubifs: Silence error output if MS_SILENT is set
2016-08-04 19:51:49 -04:00
Linus Torvalds
9e0243db61 Merge branch 'for-linus-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml
Pull UML updates from Richard Weinberger:
 "Beside of various fixes this also contains patches to enable features
  such was Kcov, kmemleak and TRACE_IRQFLAGS_SUPPORT on UML"

* 'for-linus-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
  hostfs: Freeing an ERR_PTR in hostfs_fill_sb_common()
  um: Support kcov
  um: Enable TRACE_IRQFLAGS_SUPPORT
  um: Use asm-generic/irqflags.h
  um: Fix possible deadlock in sig_handler_common()
  um: Select HAVE_DEBUG_KMEMLEAK
  um: Setup physical memory in setup_arch()
  um: Eliminate null test after alloc_bootmem
2016-08-04 19:37:59 -04:00
Jani Nikula
bdf107d87e DocBook: use DOCBOOKS="" to ignore DocBooks instead of IGNORE_DOCBOOKS=1
Instead of a separate ignore flag, use the obvious DOCBOOKS="" to ignore
all DocBook files. This is also in line with the Sphinx build being
ignored if a non-empty DOCBOOKS make variable is specified on the make
command line.

This replaces the IGNORE_DOCBOOKS introduced in

commit 547218864a
Author: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Date:   Sat Jul 9 13:12:45 2016 -0300

    doc-rst: add an option to ignore DocBooks when generating docs

and aligns with

commit 6387872c86
Author: Jani Nikula <jani.nikula@intel.com>
Date:   Fri Jul 1 15:24:44 2016 +0300

    Documentation/sphinx: skip build if user requested specific DOCBOOKS

Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Tested-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2016-08-04 16:51:33 -06:00
Linus Torvalds
b067c9045a Merge branch 'parisc-4.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux
Pull parisc updates from Helge Deller:

 - added an optimized hash implementation for parisc (George Spelvin)

 - C99 style cleanups in iomap.c (Amitoj Kaur Chawla)

 - added breaks to switch statement in PDC function (noticed by Dan
   Carpenter)

* 'parisc-4.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Change structure intialisation to C99 style in iomap.c
  parisc: Add break statements to pdc_pat_io_pci_cfg_read()
  parisc: Add <asm/hash.h>
2016-08-04 18:31:14 -04:00
Linus Torvalds
8e7106a607 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu
Pull m68knommu updates from Greg Ungerer:
 "This series is all about Nicolas flat format support for MMU systems.

  Traditional m68k no-MMU flat format binaries can now be run on m68k
  MMU enabled systems too.  The series includes some nice cleanups of
  the binfmt_flat code and converts it to using proper user space
  accessor functions.

  With all this in place you can boot and run a complete no-MMU flat
  format based user space on an MMU enabled system"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
  m68k: enable binfmt_flat on systems with an MMU
  binfmt_flat: allow compressed flat binary format to work on MMU systems
  binfmt_flat: add MMU-specific support
  binfmt_flat: update libraries' data segment pointer with userspace accessors
  binfmt_flat: use clear_user() rather than memset() to clear .bss
  binfmt_flat: use proper user space accessors with old relocs code
  binfmt_flat: use proper user space accessors with relocs processing code
  binfmt_flat: clean up create_flat_tables() and stack accesses
  binfmt_flat: use generic transfer_args_to_stack()
  elf_fdpic_transfer_args_to_stack(): make it generic
  binfmt_flat: prevent kernel dammage from corrupted executable headers
  binfmt_flat: convert printk invocations to their modern form
  binfmt_flat: assorted cleanups
  m68k: use same start_thread() on MMU and no-MMU
  m68k: fix file path comment
  m68k: fix bFLT executable running on MMU enabled systems
2016-08-04 18:04:44 -04:00
Dan Carpenter
2b11885921 nfsd: remove some dead code in nfsd_create_locked()
We changed this around in f135af1041f ('nfsd: reorganize nfsd_create')
so "dchild" can't be an error pointer any more.  Also, dchild can't be
NULL here (and dput would already handle this even if it was).

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-08-04 17:11:53 -04:00
J. Bruce Fields
fa08139d5e nfsd: drop unnecessary MAY_EXEC check from create
We need an fh_verify to make sure we at least have a dentry, but actual
permission checks happen later.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-08-04 17:11:52 -04:00
J. Bruce Fields
7142327449 nfsd: clean up bad-type check in nfsd_create_locked
Minor cleanup, no change in behavior.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-08-04 17:11:51 -04:00
J. Bruce Fields
d03d9fe476 nfsd: remove unnecessary positive-dentry check
vfs_{create,mkdir,mknod} each begin with a call to may_create(), which
returns EEXIST if the object already exists.

This check is therefore unnecessary.

(In the NFSv2 case, nfsd_proc_create also has such a check.  Contrary to
RFC 1094, our code seems to believe that a CREATE of an existing file
should succeed.  I'm leaving that behavior alone.)

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-08-04 17:11:50 -04:00
J. Bruce Fields
b44061d0b9 nfsd: reorganize nfsd_create
There's some odd logic in nfsd_create() that allows it to be called with
the parent directory either locked or unlocked.  The only already-locked
caller is NFSv2's nfsd_proc_create().  It's less confusing to split out
the unlocked case into a separate function which the NFSv2 code can call
directly.

Also fix some comments while we're here.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-08-04 17:11:49 -04:00
J. Bruce Fields
e75b23f9e3 nfsd: check d_can_lookup in fh_verify of directories
Create and other nfsd ops generally assume we can call lookup_one_len on
inodes with S_IFDIR set.  Al says that this assumption isn't true in
general, though it should be for the filesystem objects nfsd sees.

Add a check just to make sure our assumption isn't violated.

Remove a couple checks for i_op->lookup in create code.

Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-08-04 17:11:48 -04:00
J. Bruce Fields
12391d0723 nfsd: remove redundant zero-length check from create
lookup_one_len already has this check.

The only effect of this patch is to return access instead of perm in the
0-length-filename case.  I actually prefer nfserr_perm (or _inval?), but
I doubt anyone cares.

The isdotent check seems redundant too, but I worry that some client
might actually care about that strange nfserr_exist error.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-08-04 17:11:47 -04:00
Oleg Drokin
7eed34f18d nfsd: Make creates return EEXIST instead of EACCES
When doing a create (mkdir/mknod) on a name, it's worth
checking the name exists first before returning EACCES in case
the directory is not writeable by the user.
This makes return values on the client more consistent
regardless of whenever the entry there is cached in the local
cache or not.
Another positive side effect is certain programs only expect
EEXIST in that case even despite POSIX allowing any valid
error to be returned.

Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-08-04 17:11:46 -04:00
Mike Christie
abf545484d mm/block: convert rw_page users to bio op use
The rw_page users were not converted to use bio/req ops. As a result
bdev_write_page is not passing down REQ_OP_WRITE and the IOs will
be sent down as reads.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Fixes: 4e1b2d52a8 ("block, fs, drivers: remove REQ_OP compat defs and related code")

Modified by me to:

1) Drop op_flags passing into ->rw_page(), as we don't use it.
2) Make op_is_write() and friends safe to use for !CONFIG_BLOCK

Signed-off-by: Jens Axboe <axboe@fb.com>
2016-08-04 14:25:33 -06:00
Christoph Hellwig
c1c87c2ba9 loop: make do_req_filebacked more robust
Use a switch statement to iterate over the possible operations and
error out if it's an incorrect one.

Signed-off-by: Jens Axboe <axboe@fb.com>
2016-08-04 14:19:16 -06:00
Christoph Hellwig
f0225cacfe loop: don't try to use AIO for discards
Fix a fat-fingered conversion to the req_op accessors, and also
use a switch statement to make it more obvious what is being checked.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Dave Chinner <david@fromorbit.com>
Fixes: c2df40 ("drivers: use req op accessor");
Reviewed-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-08-04 14:19:16 -06:00
Jens Axboe
c0f3fd2b38 blk-mq: fix deadlock in blk_mq_register_disk() error path
If we fail registering any of the hardware queues, we call
into blk_mq_unregister_disk() with the hotplug mutex already
held. Since blk_mq_unregister_disk() attempts to acquire the
same mutex, we end up in a less than happy place.

Reported-by: Jinpu Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-08-04 14:19:16 -06:00
John Pittman
6d25ec147e Include: blkdev: Removed duplicate 'struct request;' declaration.
In include/linux/blkdev.h duplicate declarations of the request
struct exist.  Cleaned up by removing the second, unneeded
declaration.

Signed-off-by: John Pittman <jpittman@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-08-04 14:19:16 -06:00
Shaun Tancheff
b571bc606e Fixup direct bi_rw modifiers
bi_rw should be using bio_set_op_attrs to set bi_rw.

Signed-off-by: Shaun Tancheff <shaun@tancheff.com>
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: David Sterba <dsterba@suse.com>
Cc: Mike Christie <mchristi@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-08-04 14:19:16 -06:00
Dan Williams
df08c32ce3 block: fix bdi vs gendisk lifetime mismatch
The name for a bdi of a gendisk is derived from the gendisk's devt.
However, since the gendisk is destroyed before the bdi it leaves a
window where a new gendisk could dynamically reuse the same devt while a
bdi with the same name is still live.  Arrange for the bdi to hold a
reference against its "owner" disk device while it is registered.
Otherwise we can hit sysfs duplicate name collisions like the following:

 WARNING: CPU: 10 PID: 2078 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x64/0x80
 sysfs: cannot create duplicate filename '/devices/virtual/bdi/259:1'

 Hardware name: HP ProLiant DL580 Gen8, BIOS P79 05/06/2015
  0000000000000286 0000000002c04ad5 ffff88006f24f970 ffffffff8134caec
  ffff88006f24f9c0 0000000000000000 ffff88006f24f9b0 ffffffff8108c351
  0000001f0000000c ffff88105d236000 ffff88105d1031e0 ffff8800357427f8
 Call Trace:
  [<ffffffff8134caec>] dump_stack+0x63/0x87
  [<ffffffff8108c351>] __warn+0xd1/0xf0
  [<ffffffff8108c3cf>] warn_slowpath_fmt+0x5f/0x80
  [<ffffffff812a0d34>] sysfs_warn_dup+0x64/0x80
  [<ffffffff812a0e1e>] sysfs_create_dir_ns+0x7e/0x90
  [<ffffffff8134faaa>] kobject_add_internal+0xaa/0x320
  [<ffffffff81358d4e>] ? vsnprintf+0x34e/0x4d0
  [<ffffffff8134ff55>] kobject_add+0x75/0xd0
  [<ffffffff816e66b2>] ? mutex_lock+0x12/0x2f
  [<ffffffff8148b0a5>] device_add+0x125/0x610
  [<ffffffff8148b788>] device_create_groups_vargs+0xd8/0x100
  [<ffffffff8148b7cc>] device_create_vargs+0x1c/0x20
  [<ffffffff811b775c>] bdi_register+0x8c/0x180
  [<ffffffff811b7877>] bdi_register_dev+0x27/0x30
  [<ffffffff813317f5>] add_disk+0x175/0x4a0

Cc: <stable@vger.kernel.org>
Reported-by: Yi Zhang <yizhan@redhat.com>
Tested-by: Yi Zhang <yizhan@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

Fixed up missing 0 return in bdi_register_owner().

Signed-off-by: Jens Axboe <axboe@fb.com>
2016-08-04 14:19:16 -06:00
Gabriel Krisman Bertazi
71f79fb317 blk-mq: Allow timeouts to run while queue is freezing
In case a submitted request gets stuck for some reason, the block layer
can prevent the request starvation by starting the scheduled timeout work.
If this stuck request occurs at the same time another thread has started
a queue freeze, the blk_mq_timeout_work will not be able to acquire the
queue reference and will return silently, thus not issuing the timeout.
But since the request is already holding a q_usage_counter reference and
is unable to complete, it will never release its reference, preventing
the queue from completing the freeze started by first thread.  This puts
the request_queue in a hung state, forever waiting for the freeze
completion.

This was observed while running IO to a NVMe device at the same time we
toggled the CPU hotplug code. Eventually, once a request got stuck
requiring a timeout during a queue freeze, we saw the CPU Hotplug
notification code get stuck inside blk_mq_freeze_queue_wait, as shown in
the trace below.

[c000000deaf13690] [c000000deaf13738] 0xc000000deaf13738 (unreliable)
[c000000deaf13860] [c000000000015ce8] __switch_to+0x1f8/0x350
[c000000deaf138b0] [c000000000ade0e4] __schedule+0x314/0x990
[c000000deaf13940] [c000000000ade7a8] schedule+0x48/0xc0
[c000000deaf13970] [c0000000005492a4] blk_mq_freeze_queue_wait+0x74/0x110
[c000000deaf139e0] [c00000000054b6a8] blk_mq_queue_reinit_notify+0x1a8/0x2e0
[c000000deaf13a40] [c0000000000e7878] notifier_call_chain+0x98/0x100
[c000000deaf13a90] [c0000000000b8e08] cpu_notify_nofail+0x48/0xa0
[c000000deaf13ac0] [c0000000000b92f0] _cpu_down+0x2a0/0x400
[c000000deaf13b90] [c0000000000b94a8] cpu_down+0x58/0xa0
[c000000deaf13bc0] [c0000000006d5dcc] cpu_subsys_offline+0x2c/0x50
[c000000deaf13bf0] [c0000000006cd244] device_offline+0x104/0x140
[c000000deaf13c30] [c0000000006cd40c] online_store+0x6c/0xc0
[c000000deaf13c80] [c0000000006c8c78] dev_attr_store+0x68/0xa0
[c000000deaf13cc0] [c0000000003974d0] sysfs_kf_write+0x80/0xb0
[c000000deaf13d00] [c0000000003963e8] kernfs_fop_write+0x188/0x200
[c000000deaf13d50] [c0000000002e0f6c] __vfs_write+0x6c/0xe0
[c000000deaf13d90] [c0000000002e1ca0] vfs_write+0xc0/0x230
[c000000deaf13de0] [c0000000002e2cdc] SyS_write+0x6c/0x110
[c000000deaf13e30] [c000000000009204] system_call+0x38/0xb4

The fix is to allow the timeout work to execute in the window between
dropping the initial refcount reference and the release of the last
reference, which actually marks the freeze completion.  This can be
achieved with percpu_refcount_tryget, which does not require the counter
to be alive.  This way the timeout work can do it's job and terminate a
stuck request even during a freeze, returning its reference and avoiding
the deadlock.

Allowing the timeout to run is just a part of the fix, since for some
devices, we might get stuck again inside the device driver's timeout
handler, should it attempt to allocate a new request in that path -
which is a quite common action for Abort commands, which need to be sent
after a timeout.  In NVMe, for instance, we call blk_mq_alloc_request
from inside the timeout handler, which will fail during a freeze, since
it also tries to acquire a queue reference.

I considered a similar change to blk_mq_alloc_request as a generic
solution for further device driver hangs, but we can't do that, since it
would allow new requests to disturb the freeze process.  I thought about
creating a new function in the block layer to support unfreezable
requests for these occasions, but after working on it for a while, I
feel like this should be handled in a per-driver basis.  I'm now
experimenting with changes to the NVMe timeout path, but I'm open to
suggestions of ways to make this generic.

Signed-off-by: Gabriel Krisman Bertazi <krisman@linux.vnet.ibm.com>
Cc: Brian King <brking@linux.vnet.ibm.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: linux-nvme@lists.infradead.org
Cc: linux-block@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-08-04 14:19:16 -06:00
Vegard Nossum
97240963eb nbd: fix race in ioctl
Quentin ran into this bug:

WARNING: CPU: 64 PID: 10085 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x65/0x80
sysfs: cannot create duplicate filename '/devices/virtual/block/nbd3/pid'
Modules linked in: nbd
CPU: 64 PID: 10085 Comm: qemu-nbd Tainted: G      D         4.6.0+ #7
 0000000000000000 ffff8820330bba68 ffffffff814b8791 ffff8820330bbac8
 0000000000000000 ffff8820330bbab8 ffffffff810d04ab ffff8820330bbaa8
 0000001f00000296 0000000000017681 ffff8810380bf000 ffffffffa0001790
Call Trace:
 [<ffffffff814b8791>] dump_stack+0x4d/0x6c
 [<ffffffff810d04ab>] __warn+0xdb/0x100
 [<ffffffff810d0574>] warn_slowpath_fmt+0x44/0x50
 [<ffffffff81218c65>] sysfs_warn_dup+0x65/0x80
 [<ffffffff81218a02>] sysfs_add_file_mode_ns+0x172/0x180
 [<ffffffff81218a35>] sysfs_create_file_ns+0x25/0x30
 [<ffffffff81594a76>] device_create_file+0x36/0x90
 [<ffffffffa0000e8d>] __nbd_ioctl+0x32d/0x9b0 [nbd]
 [<ffffffff814cc8e8>] ? find_next_bit+0x18/0x20
 [<ffffffff810f7c29>] ? select_idle_sibling+0xe9/0x120
 [<ffffffff810f6cd7>] ? __enqueue_entity+0x67/0x70
 [<ffffffff810f9bf0>] ? enqueue_task_fair+0x630/0xe20
 [<ffffffff810efa76>] ? resched_curr+0x36/0x70
 [<ffffffff810f0078>] ? check_preempt_curr+0x78/0x90
 [<ffffffff810f00a2>] ? ttwu_do_wakeup+0x12/0x80
 [<ffffffff810f01b1>] ? ttwu_do_activate.constprop.86+0x61/0x70
 [<ffffffff810f0c15>] ? try_to_wake_up+0x185/0x2d0
 [<ffffffff810f0d6d>] ? default_wake_function+0xd/0x10
 [<ffffffff81105471>] ? autoremove_wake_function+0x11/0x40
 [<ffffffffa0001577>] nbd_ioctl+0x67/0x94 [nbd]
 [<ffffffff814ac0fd>] blkdev_ioctl+0x14d/0x940
 [<ffffffff811b0da2>] ? put_pipe_info+0x22/0x60
 [<ffffffff811d96cc>] block_ioctl+0x3c/0x40
 [<ffffffff811ba08d>] do_vfs_ioctl+0x8d/0x5e0
 [<ffffffff811aa329>] ? ____fput+0x9/0x10
 [<ffffffff810e9092>] ? task_work_run+0x72/0x90
 [<ffffffff811ba627>] SyS_ioctl+0x47/0x80
 [<ffffffff8185f5df>] entry_SYSCALL_64_fastpath+0x17/0x93
---[ end trace 7899b295e4f850c8 ]---

It seems fairly obvious that device_create_file() is not being protected
from being run concurrently on the same nbd.

Quentin found the following relevant commits:

1a2ad21 nbd: add locking to nbd_ioctl
90b8f28 [PATCH] end of methods switch: remove the old ones
d4430d6 [PATCH] beginning of methods conversion
08f8585 [PATCH] move block_device_operations to blkdev.h

It would seem that the race was introduced in the process of moving nbd
from BKL to unlocked ioctls.

By setting nbd->task_recv while the mutex is held, we can prevent other
processes from running concurrently (since nbd->task_recv is also checked
while the mutex is held).

Reported-and-tested-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Markus Pargmann <mpa@pengutronix.de>
Cc: Paul Clements <paul.clements@steeleye.com>
Cc: Pavel Machek <pavel@suse.cz>
Cc: Jens Axboe <axboe@fb.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-08-04 14:19:16 -06:00