The mcs_spinlock code is not meant (or suitable) as a generic locking
primitive, therefore take it away from the normal includes and place
it in kernel/locking/.
This way the locking primitives implemented there can use it as part
of their implementation but we do not risk it getting used
inapropriately.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/n/tip-byirmpamgr7h25m5kyavwpzx@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Test-case:
DEFINE_MUTEX(m1);
DEFINE_MUTEX(m2);
DEFINE_MUTEX(mx);
void lockdep_should_complain(void)
{
lockdep_set_novalidate_class(&mx);
// m1 -> mx -> m2
mutex_lock(&m1);
mutex_lock(&mx);
mutex_lock(&m2);
mutex_unlock(&m2);
mutex_unlock(&mx);
mutex_unlock(&m1);
// m2 -> m1 ; should trigger the warning
mutex_lock(&m2);
mutex_lock(&m1);
mutex_unlock(&m1);
mutex_unlock(&m2);
}
this doesn't trigger any warning, lockdep can't detect the trivial
deadlock.
This is because lock(&mx) correctly avoids m1 -> mx dependency, it
skips validate_chain() due to mx->check == 0. But lock(&m2) wrongly
adds mx -> m2 and thus m1 -> m2 is not created.
rcu_lock_acquire()->lock_acquire(check => 0) is fine due to read == 2,
so currently only __lockdep_no_validate__ can trigger this problem.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140120182010.GA26498@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The "int check" argument of lock_acquire() and held_lock->check are
misleading. This is actually a boolean: 2 means "true", everything
else is "false".
And there is no need to pass 1 or 0 to lock_acquire() depending on
CONFIG_PROVE_LOCKING, __lock_acquire() checks prove_locking at the
start and clears "check" if !CONFIG_PROVE_LOCKING.
Note: probably we can simply kill this member/arg. The only explicit
user of check => 0 is rcu_lock_acquire(), perhaps we can change it to
use lock_acquire(trylock =>, read => 2). __lockdep_no_validate means
check => 0 implicitly, but we can change validate_chain() to check
hlock->instance->key instead. Not to mention it would be nice to get
rid of lockdep_set_novalidate_class().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140120182006.GA26495@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull misc kbuild changes from Michal Marek:
"The non-critical part of kbuild is small this time:
- Three fixes for make deb-pkg
- A new coccinelle check
One of the deb-pkg fixes is a leftover from the last merge window,
hence the merge commit"
* 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
deb-pkg: Fix building for MIPS big-endian or ARM OABI
deb-pkg: Fix cross-building linux-headers package
scripts: Coccinelle script for pm_runtime_* return checks with IS_ERR_VALUE
deb-pkg: Inhibit initramfs builders if CONFIG_BLK_DEV_INITRD is not set
Both proc files are writeable and used for configuring cells. But
there is missing correct mode flag for writeable files. Without
this patch both proc files are read only.
[ It turns out they aren't really read-only, since root can write to
them even if the write bit isn't set due to CAP_DAC_OVERRIDE ]
Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With commit d8d14bd09c ("fs/compat: fix lookup_dcookie() parameter
handling") I changed the type of the len parameter of the
lookup_dcookie() syscall.
However I missed that there was still a stale declaration in
arch/tile/.. which now causes a compile error on tile:
In file included from fs/dcookies.c:28:0:
include/linux/compat.h:425:17: error: conflicting types for 'compat_sys_lookup_dcookie'
fs/dcookies.c:207:1: error: conflicting types for 'compat_sys_lookup_dcookie'
Simply remove the declaration in the tile architecture, which is only a
leftover from before the different compat lookup_dcookie() versions have
been merged. The correct declaration is now in include/linux/compat.h
The build error was reported by Fenguang's build bot.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull cifs fixes from Steve French:
"A set of cifs fixes (mostly for symlinks, and SMB2 xattrs) and
cleanups"
* 'for-linus' of git://git.samba.org/sfrench/cifs-2.6:
cifs: Fix check for regular file in couldbe_mf_symlink()
[CIFS] Fix SMB2 mounts so they don't try to set or get xattrs via cifs
CIFS: Cleanup cifs open codepath
CIFS: Remove extra indentation in cifs_sfu_type
CIFS: Cleanup cifs_mknod
CIFS: Cleanup CIFSSMBOpen
cifs: Add support for follow_link on dfs shares under posix extensions
cifs: move unix extension call to cifs_query_symlink()
cifs: Re-order M-F Symlink code
cifs: Add create MFSymlinks to protocol ops struct
cifs: use protocol specific call for query_mf_symlink()
cifs: Rename MF symlink function names
cifs: Rename and cleanup open_query_close_cifs_symlink()
cifs: Fix memory leak in cifs_hardlink()
Pull vfs fixes from Al Viro:
"Several obvious fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
Fix mountpoint reference leakage in linkat
hfsplus: use xattr handlers for removexattr
Typo in compat_sys_lseek() declaration
fs/super.c: sync ro remount after blocking writers
vfs: unexport the getname() symbol
Pull rtl8812ae staging wireless driver from Greg KH:
"Here's a single staging driver for a wireless chipset that has shown
up in the SteamBox hardware. It is merged separately from the "main"
staging pull request to sync up with the wireless api changes that
came in from the networking tree.
It's self-contained and works for me and others. Larry will be
replacing it with a "real" driver for 3.15, but for now this one is
needed"
* tag 'staging-3.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
staging: r8821ae: Enable build by reverting BROKEN marking
staging: r8821ae: Fix build problems
Staging: rtl8812ae: disable due to build errors
Staging: rtl8821ae: add TODO file
Staging: rtl8821ae: removed unused functions and variables
Staging: rtl8821ae: rc.c: fix up function prototypes
Staging: rtl8812ae: Add Realtek 8821 PCI WIFI driver
Revert commit ef83b0781a "PCI: Remove from bus_list and release
resources in pci_release_dev()" that made some nasty race conditions
become possible. For example, if a Thunderbolt link is unplugged
and then replugged immediately, the pci_release_dev() resulting from
the hot-remove code path may be racing with the hot-add code path
which after that commit causes various kinds of breakage to happen
(up to and including a hard crash of the whole system).
Moreover, the problem that commit ef83b0781a attempted to address
cannot happen any more after commit 8a4c5c329d "PCI: Check parent
kobject in pci_destroy_dev()", because pci_destroy_dev() will now
return immediately if it has already been executed for the given
device.
Note, however, that the invocation of msi_remove_pci_irq_vectors()
removed by commit ef83b0781a from pci_free_resources() along with
the other changes made by it is not added back because of subsequent
code changes depending on that modification.
Fixes: ef83b0781a (PCI: Remove from bus_list and release resources in pci_release_dev())
Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull NFS client bugfixes from Trond Myklebust:
"Highlights:
- Fix several races in nfs_revalidate_mapping
- NFSv4.1 slot leakage in the pNFS files driver
- Stable fix for a slot leak in nfs40_sequence_done
- Don't reject NFSv4 servers that support ACLs with only ALLOW aces"
* tag 'nfs-for-3.14-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
nfs: initialize the ACL support bits to zero.
NFSv4.1: Cleanup
NFSv4.1: Clean up nfs41_sequence_done
NFSv4: Fix a slot leak in nfs40_sequence_done
NFSv4.1 free slot before resending I/O to MDS
nfs: add memory barriers around NFS_INO_INVALID_DATA and NFS_INO_INVALIDATING
NFS: Fix races in nfs_revalidate_mapping
sunrpc: turn warn_gssd() log message into a dprintk()
NFS: fix the handling of NFS_INO_INVALID_DATA flag in nfs_revalidate_mapping
nfs: handle servers that support only ALLOW ACE type.
Pull sound fixes from Takashi Iwai:
"The big chunks here are the updates for oxygen driver for Xonar DG
devices, which were slipped from the previous pull request. They are
device-specific and thus not too dangerous.
Other than that, all patches are small bug fixes, mainly for Samsung
build fixes, a few HD-audio enhancements, and other misc ASoC fixes.
(And this time ASoC merge is less than Octopus, lucky seven :)"
* tag 'sound-fix-3.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (42 commits)
ALSA: hda/hdmi - allow PIN_OUT to be dynamically enabled
ALSA: hda - add headset mic detect quirks for another Dell laptop
ALSA: oxygen: Xonar DG(X): cleanup and minor changes
ALSA: oxygen: Xonar DG(X): modify high-pass filter control
ALSA: oxygen: Xonar DG(X): modify input select functions
ALSA: oxygen: Xonar DG(X): modify capture volume functions
ALSA: oxygen: Xonar DG(X): use headphone volume control
ALSA: oxygen: Xonar DG(X): modify playback output select
ALSA: oxygen: Xonar DG(X): capture from I2S channel 1, not 2
ALSA: oxygen: Xonar DG(X): move the mixer code into another file
ALSA: oxygen: modify CS4245 register dumping function
ALSA: oxygen: modify adjust_dg_dac_routing function
ALSA: oxygen: Xonar DG(X): modify DAC/ADC parameters function
ALSA: oxygen: Xonar DG(X): modify initialization functions
ALSA: oxygen: Xonar DG(X): add new CS4245 SPI functions
ALSA: oxygen: additional definitions for the Xonar DG/DGX card
ALSA: oxygen: change description of the xonar_dg.c file
ALSA: oxygen: export oxygen_update_dac_routing symbol
ALSA: oxygen: add mute mask for the OXYGEN_PLAY_ROUTING register
ALSA: oxygen: modify the SPI writing function
...
Pull SCSI target updates from Nicholas Bellinger:
"The highlights this round include:
- add support for SCSI Referrals (Hannes)
- add support for T10 DIF into target core (nab + mkp)
- add support for T10 DIF emulation in FILEIO + RAMDISK backends (Sagi + nab)
- add support for T10 DIF -> bio_integrity passthrough in IBLOCK backend (nab)
- prep changes to iser-target for >= v3.15 T10 DIF support (Sagi)
- add support for qla2xxx N_Port ID Virtualization - NPIV (Saurav + Quinn)
- allow percpu_ida_alloc() to receive task state bitmask (Kent)
- fix >= v3.12 iscsi-target session reset hung task regression (nab)
- fix >= v3.13 percpu_ref se_lun->lun_ref_active race (nab)
- fix a long-standing network portal creation race (Andy)"
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (51 commits)
target: Fix percpu_ref_put race in transport_lun_remove_cmd
target/iscsi: Fix network portal creation race
target: Report bad sector in sense data for DIF errors
iscsi-target: Convert gfp_t parameter to task state bitmask
iscsi-target: Fix connection reset hang with percpu_ida_alloc
percpu_ida: Make percpu_ida_alloc + callers accept task state bitmask
iscsi-target: Pre-allocate more tags to avoid ack starvation
qla2xxx: Configure NPIV fc_vport via tcm_qla2xxx_npiv_make_lport
qla2xxx: Enhancements to enable NPIV support for QLOGIC ISPs with TCM/LIO.
qla2xxx: Fix scsi_host leak on qlt_lport_register callback failure
IB/isert: pass scatterlist instead of cmd to fast_reg_mr routine
IB/isert: Move fastreg descriptor creation to a function
IB/isert: Avoid frwr notation, user fastreg
IB/isert: seperate connection protection domains and dma MRs
tcm_loop: Enable DIF/DIX modes in SCSI host LLD
target/rd: Add DIF protection into rd_execute_rw
target/rd: Add support for protection SGL setup + release
target/rd: Refactor rd_build_device_space + rd_release_device_space
target/file: Add DIF protection support to fd_execute_rw
target/file: Add DIF protection init/format support
...
Recent changes to retry on ESTALE in linkat
(commit 442e31ca5a)
introduced a mountpoint reference leak and a small memory
leak in case a filesystem link operation returns ESTALE
which is pretty normal for distributed filesystems like
lustre, nfs and so on.
Free old_path in such a case.
[AV: there was another missing path_put() nearby - on the previous
goto retry]
Signed-off-by: Oleg Drokin: <green@linuxhacker.ru>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pyll ARM64 patches from Catalin Marinas:
- Build fix with DMA_CMA enabled
- Introduction of PTE_WRITE to distinguish between writable but clean
and truly read-only pages
- FIQs enabling/disabling clean-up (they aren't used on arm64)
- CPU resume fix for the per-cpu offset restoring
- Code comment typos
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: mm: Introduce PTE_WRITE
arm64: mm: Remove PTE_BIT_FUNC macro
arm64: FIQs are unused
arm64: mm: fix the function name in comment of cpu_do_switch_mm
arm64: fix build error if DMA_CMA is enabled
arm64: kernel: fix per-cpu offset restore on resume
arm64: mm: fix the function name in comment of __flush_dcache_area
arm64: mm: use ubfm for dcache_line_size
Peter Zijlstra
Finn Thain
Heiko Carstens
Ingo Molnar
Oleg Nesterov
Tim Chen
Johannes Berg
Linus Torvalds
Pali Rohár
Rafael J. Wysocki
Oleg Drokin