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Jiri reported a machine stuck in multi_cpu_stop() with
migrate_swap_stop() as function and with the following src,dst cpu
pairs: {11, 4} {13, 11} { 4, 13}
4 11 13
cpuM: queue(4 ,13)
*Ma
cpuN: queue(13,11)
*N Na
*M Mb
cpuO: queue(11, 4)
*O Oa
*Nb
*Ob
Where *X denotes the cpu running the queueing of cpu-X and X[ab] denotes
the first/second queued work.
You'll observe the top of the workqueue for each cpu: 4,11,13 to be work
from cpus: M, O, N resp. IOW. deadlock.
Do away with the queueing trickery and introduce lg_double_lock() to
lock both CPUs and fully serialize the stop_two_cpus() callers instead
of the partial (and buggy) serialization we have now.
Reported-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20150605153023.GH19282@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
preempt.h has two seperate "#ifdef CONFIG_PREEMPT" sections: one to
define preempt_enable() and another to define preempt_enable_notrace().
Lets gather both.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1433432349-1021-4-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
preempt_schedule_context() is a tracing safe preemption point but it's
only used when CONFIG_CONTEXT_TRACKING=y. Other configs have tracing
recursion issues since commit:
b30f0e3ffedf ("sched/preempt: Optimize preemption operations on __schedule() callers")
introduced function based preemp_count_*() ops.
Lets make it available on all configs and give it a more appropriate
name for its new position.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1433432349-1021-3-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull networking fixes from David Miller:
1) Various VTI tunnel (mark handling, PMTU) bug fixes from Alexander
Duyck and Steffen Klassert.
2) Revert ethtool PHY query change, it wasn't correct. The PHY address
selected by the driver running the PHY to MAC connection decides
what PHY address GET ethtool operations return information from.
3) Fix handling of sequence number bits for encryption IV generation in
ESP driver, from Herbert Xu.
4) UDP can return -EAGAIN when we hit a bad checksum on receive, even
when there are other packets in the receive queue which is wrong.
Just respect the error returned from the generic socket recv
datagram helper. From Eric Dumazet.
5) Fix BNA driver firmware loading on big-endian systems, from Ivan
Vecera.
6) Fix regression in that we were inheriting the congestion control of
the listening socket for new connections, the intended behavior
always was to use the default in this case. From Neal Cardwell.
7) Fix NULL deref in brcmfmac driver, from Arend van Spriel.
8) OTP parsing fix in iwlwifi from Liad Kaufman.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (26 commits)
vti6: Add pmtu handling to vti6_xmit.
Revert "net: core: 'ethtool' issue with querying phy settings"
bnx2x: Move statistics implementation into semaphores
xen: netback: read hotplug script once at start of day.
xen: netback: fix printf format string warning
Revert "netfilter: ensure number of counters is >0 in do_replace()"
net: dsa: Properly propagate errors from dsa_switch_setup_one
tcp: fix child sockets to use system default congestion control if not set
udp: fix behavior of wrong checksums
sfc: free multiple Rx buffers when required
bna: fix soft lock-up during firmware initialization failure
bna: remove unreasonable iocpf timer start
bna: fix firmware loading on big-endian machines
bridge: fix br_multicast_query_expired() bug
via-rhine: Resigning as maintainer
brcmfmac: avoid null pointer access when brcmf_msgbuf_get_pktid() fails
mac80211: Fix mac80211.h docbook comments
iwlwifi: nvm: fix otp parsing in 8000 hw family
iwlwifi: pcie: fix tracking of cmd_in_flight
ip_vti/ip6_vti: Preserve skb->mark after rcv_cb call
...
Fixes userspace compilation error:
error: unknown type name ‘__virtio16’
__virtio16 tag;
Signed-off-by: Mikko Rapeli <mikko.rapeli@iki.fi>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Linux 3.17 and earlier are explicitly engineered so that if the app
doesn't specifically request a CC module on a listener before the SYN
arrives, then the child gets the system default CC when the connection
is established. See tcp_init_congestion_control() in 3.17 or earlier,
which says "if no choice made yet assign the current value set as
default". The change ("net: tcp: assign tcp cong_ops when tcp sk is
created") altered these semantics, so that children got their parent
listener's congestion control even if the system default had changed
after the listener was created.
This commit returns to those original semantics from 3.17 and earlier,
since they are the original semantics from 2007 in 4d4d3d1e8 ("[TCP]:
Congestion control initialization."), and some Linux congestion
control workflows depend on that.
In summary, if a listener socket specifically sets TCP_CONGESTION to
"x", or the route locks the CC module to "x", then the child gets
"x". Otherwise the child gets current system default from
net.ipv4.tcp_congestion_control. That's the behavior in 3.17 and
earlier, and this commit restores that.
Fixes: 55d8694fa82c ("net: tcp: assign tcp cong_ops when tcp sk is created")
Cc: Florian Westphal <fw@strlen.de>
Cc: Daniel Borkmann <dborkman@redhat.com>
Cc: Glenn Judd <glenn.judd@morganstanley.com>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull SCSI target fixes from Nicholas Bellinger:
"These are mostly minor fixes, with the exception of the following that
address fall-out from recent v4.1-rc1 changes:
- regression fix related to the big fabric API registration changes
and configfs_depend_item() usage, that required cherry-picking one
of HCH's patches from for-next to address the issue for v4.1 code.
- remaining TCM-USER -v2 related changes to enforce full CDB
passthrough from Andy + Ilias.
Also included is a target_core_pscsi driver fix from Andy that
addresses a long standing issue with a Scsi_Host reference being
leaked on PSCSI device shutdown"
* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
iser-target: Fix error path in isert_create_pi_ctx()
target: Use a PASSTHROUGH flag instead of transport_types
target: Move passthrough CDB parsing into a common function
target/user: Only support full command pass-through
target/user: Update example code for new ABI requirements
target/pscsi: Don't leak scsi_host if hba is VIRTUAL_HOST
target: Fix se_tpg_tfo->tf_subsys regression + remove tf_subsystem
target: Drop signal_pending checks after interruptible lock acquire
target: Add missing parentheses
target: Fix bidi command handling
target/user: Disallow full passthrough (pass_level=0)
ISCSI: fix minor memory leak
I'd already sent the same fix for -next, but Ben Hutchings
noted it's necessary in 4.1.
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Merge tag 'mac80211-for-davem-2015-05-28' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211
Johannes Berg says:
====================
This just has a single docbook build fix. In my confusion
I'd already sent the same fix for -next, but Ben Hutchings
noted it's necessary in 4.1.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
It seems like we only care if a transport is passthrough or not. Convert
transport_type to a flags field and replace TRANSPORT_PLUGIN_* with a
flag, TRANSPORT_FLAG_PASSTHROUGH.
Signed-off-by: Andy Grover <agrover@redhat.com>
Reviewed-by: Ilias Tsitsimpis <iliastsi@arrikto.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Aside from whether they handle BIDI ops or not, parsing of the CDB by
kernel and user SCSI passthrough modules should be identical. Move this
into a new passthrough_parse_cdb() and call it from tcm-pscsi and tcm-user.
Reported-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ilias Tsitsimpis <iliastsi@arrikto.com>
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
There is just one configfs subsystem in the target code, so we might as
well add two helpers to reference / unreference it from the core code
instead of passing pointers to it around.
This fixes a regression introduced for v4.1-rc1 with commit 9ac8928e6,
where configfs_depend_item() callers using se_tpg_tfo->tf_subsys would
fail, because the assignment from the original target_core_subsystem[]
is no longer happening at target_register_template() time.
(Fix target_core_exit_configfs pointer dereference - Sagi)
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Himanshu Madhani <himanshu.madhani@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Changes in this update:
o regression fix for new rename whiteout code
o regression fixes for new superblock generic per-cpu counter code
o fix for incorrect error return sign introduced in 3.17
o metadata corruption fixes that need to go back to -stable kernels
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Merge tag 'xfs-for-linus-4.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs
Pull xfs fixes from Dave Chinner:
"This is a little larger than I'd like late in the release cycle, but
all the fixes are for regressions introduced in the 4.1-rc1 merge, or
are needed back in -stable kernels fairly quickly as they are
filesystem corruption or userspace visible correctness issues.
Changes in this update:
- regression fix for new rename whiteout code
- regression fixes for new superblock generic per-cpu counter code
- fix for incorrect error return sign introduced in 3.17
- metadata corruption fixes that need to go back to -stable kernels"
* tag 'xfs-for-linus-4.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs:
xfs: fix broken i_nlink accounting for whiteout tmpfile inode
xfs: xfs_iozero can return positive errno
xfs: xfs_attr_inactive leaves inconsistent attr fork state behind
xfs: extent size hints can round up extents past MAXEXTLEN
xfs: inode and free block counters need to use __percpu_counter_compare
percpu_counter: batch size aware __percpu_counter_compare()
xfs: use percpu_counter_read_positive for mp->m_icount
Merge misc fixes from Andrew Morton:
"10 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
scripts/gdb: fix lx-lsmod refcnt
omfs: fix potential integer overflow in allocator
omfs: fix sign confusion for bitmap loop counter
omfs: set error return when d_make_root() fails
fs, omfs: add NULL terminator in the end up the token list
MAINTAINERS: update CAPABILITIES pattern
fs/binfmt_elf.c:load_elf_binary(): return -EINVAL on zero-length mappings
tracing/mm: don't trace mm_page_pcpu_drain on offline cpus
tracing/mm: don't trace mm_page_free on offline cpus
tracing/mm: don't trace kmem_cache_free on offline cpus
Two fixes which got lost in my recent distraction. One is a weird
cpumask function which needed to be rewritten, the other is a module
bug which is cc:stable.
Thanks,
Rusty.
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Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull fixes for cpumask and modules from Rusty Russell:
"** NOW WITH TESTING! **
Two fixes which got lost in my recent distraction. One is a weird
cpumask function which needed to be rewritten, the other is a module
bug which is cc:stable"
* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
cpumask_set_cpu_local_first => cpumask_local_spread, lament
module: Call module notifier on failure after complete_formation()
Since tracepoints use RCU for protection, they must not be called on
offline cpus. trace_mm_page_pcpu_drain can be called on an offline cpu
in this scenario caught by LOCKDEP:
===============================
[ INFO: suspicious RCU usage. ]
4.1.0-rc1+ #9 Not tainted
-------------------------------
include/trace/events/kmem.h:265 suspicious rcu_dereference_check() usage!
other info that might help us debug this:
RCU used illegally from offline CPU!
rcu_scheduler_active = 1, debug_locks = 1
1 lock held by swapper/5/0:
#0: (&(&zone->lock)->rlock){..-...}, at: [<c0000000002073b0>] .free_pcppages_bulk+0x70/0x920
stack backtrace:
CPU: 5 PID: 0 Comm: swapper/5 Not tainted 4.1.0-rc1+ #9
Call Trace:
.dump_stack+0x98/0xd4 (unreliable)
.lockdep_rcu_suspicious+0x108/0x170
.free_pcppages_bulk+0x60c/0x920
.free_hot_cold_page+0x208/0x280
.destroy_context+0x90/0xd0
.__mmdrop+0x58/0x160
.idle_task_exit+0xf0/0x100
.pnv_smp_cpu_kill_self+0x58/0x2c0
.cpu_die+0x34/0x50
.arch_cpu_idle_dead+0x20/0x40
.cpu_startup_entry+0x708/0x7a0
.start_secondary+0x36c/0x3a0
start_secondary_prolog+0x10/0x14
Fix this by converting mm_page_pcpu_drain trace point into
TRACE_EVENT_CONDITION where condition is cpu_online(smp_processor_id())
Signed-off-by: Shreyas B. Prabhu <shreyas@linux.vnet.ibm.com>
Reviewed-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since tracepoints use RCU for protection, they must not be called on
offline cpus. trace_mm_page_free can be called on an offline cpu in this
scenario caught by LOCKDEP:
===============================
[ INFO: suspicious RCU usage. ]
4.1.0-rc1+ #9 Not tainted
-------------------------------
include/trace/events/kmem.h:170 suspicious rcu_dereference_check() usage!
other info that might help us debug this:
RCU used illegally from offline CPU!
rcu_scheduler_active = 1, debug_locks = 1
no locks held by swapper/1/0.
stack backtrace:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.1.0-rc1+ #9
Call Trace:
.dump_stack+0x98/0xd4 (unreliable)
.lockdep_rcu_suspicious+0x108/0x170
.free_pages_prepare+0x494/0x680
.free_hot_cold_page+0x50/0x280
.destroy_context+0x90/0xd0
.__mmdrop+0x58/0x160
.idle_task_exit+0xf0/0x100
.pnv_smp_cpu_kill_self+0x58/0x2c0
.cpu_die+0x34/0x50
.arch_cpu_idle_dead+0x20/0x40
.cpu_startup_entry+0x708/0x7a0
.start_secondary+0x36c/0x3a0
start_secondary_prolog+0x10/0x14
Fix this by converting mm_page_free trace point into TRACE_EVENT_CONDITION
where condition is cpu_online(smp_processor_id())
Signed-off-by: Shreyas B. Prabhu <shreyas@linux.vnet.ibm.com>
Reviewed-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since tracepoints use RCU for protection, they must not be called on
offline cpus. trace_kmem_cache_free can be called on an offline cpu in
this scenario caught by LOCKDEP:
===============================
[ INFO: suspicious RCU usage. ]
4.1.0-rc1+ #9 Not tainted
-------------------------------
include/trace/events/kmem.h:148 suspicious rcu_dereference_check() usage!
other info that might help us debug this:
RCU used illegally from offline CPU!
rcu_scheduler_active = 1, debug_locks = 1
no locks held by swapper/1/0.
stack backtrace:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.1.0-rc1+ #9
Call Trace:
.dump_stack+0x98/0xd4 (unreliable)
.lockdep_rcu_suspicious+0x108/0x170
.kmem_cache_free+0x344/0x4b0
.__mmdrop+0x4c/0x160
.idle_task_exit+0xf0/0x100
.pnv_smp_cpu_kill_self+0x58/0x2c0
.cpu_die+0x34/0x50
.arch_cpu_idle_dead+0x20/0x40
.cpu_startup_entry+0x708/0x7a0
.start_secondary+0x36c/0x3a0
start_secondary_prolog+0x10/0x14
Fix this by converting kmem_cache_free trace point into
TRACE_EVENT_CONDITION where condition is cpu_online(smp_processor_id())
Signed-off-by: Shreyas B. Prabhu <shreyas@linux.vnet.ibm.com>
Reported-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Reviewed-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
XFS uses non-stanard batch sizes for avoiding frequent global
counter updates on it's allocated inode counters, as they increment
or decrement in batches of 64 inodes. Hence the standard percpu
counter batch of 32 means that the counter is effectively a global
counter. Currently Xfs uses a batch size of 128 so that it doesn't
take the global lock on every single modification.
However, Xfs also needs to compare accurately against zero, which
means we need to use percpu_counter_compare(), and that has a
hard-coded batch size of 32, and hence will spuriously fail to
detect when it is supposed to use precise comparisons and hence
the accounting goes wrong.
Add __percpu_counter_compare() to take a custom batch size so we can
use it sanely in XFS and factor percpu_counter_compare() to use it.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Dave Chinner <david@fromorbit.com>
A couple of enums in mac80211.h became structures recently, but the
comments didn't follow suit, leading to errors like:
Error(.//include/net/mac80211.h:367): Cannot parse enum!
Documentation/DocBook/Makefile:93: recipe for target 'Documentation/DocBook/80211.xml' failed
make[1]: *** [Documentation/DocBook/80211.xml] Error 1
Makefile:1361: recipe for target 'mandocs' failed
make: *** [mandocs] Error 2
Fix the comments comments accordingly. Added a couple of other small
comment fixes while I was there to silence other recently-added docbook
warnings.
Reported-by: Jim Davis <jim.epost@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
da91309e0a7e (cpumask: Utility function to set n'th cpu...) created a
genuinely weird function. I never saw it before, it went through DaveM.
(He only does this to make us other maintainers feel better about our own
mistakes.)
cpumask_set_cpu_local_first's purpose is say "I need to spread things
across N online cpus, choose the ones on this numa node first"; you call
it in a loop.
It can fail. One of the two callers ignores this, the other aborts and
fails the device open.
It can fail in two ways: allocating the off-stack cpumask, or through a
convoluted codepath which AFAICT can only occur if cpu_online_mask
changes. Which shouldn't happen, because if cpu_online_mask can change
while you call this, it could return a now-offline cpu anyway.
It contains a nonsensical test "!cpumask_of_node(numa_node)". This was
drawn to my attention by Geert, who said this causes a warning on Sparc.
It sets a single bit in a cpumask instead of returning a cpu number,
because that's what the callers want.
It could be made more efficient by passing the previous cpu rather than
an index, but that would be more invasive to the callers.
Fixes: da91309e0a7e8966d916a74cce42ed170fde06bf
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (then rebased)
Tested-by: Amir Vadai <amirv@mellanox.com>
Acked-by: Amir Vadai <amirv@mellanox.com>
Acked-by: David S. Miller <davem@davemloft.net>
Pull networking fixes from David Miller:
1) Don't use MMIO on certain iwlwifi devices otherwise we get a
firmware crash.
2) Don't corrupt the GRO lists of mac80211 contexts by doing sends via
timer interrupt, from Johannes Berg.
3) SKB tailroom is miscalculated in AP_VLAN crypto code, from Michal
Kazior.
4) Fix fw_status memory leak in iwlwifi, from Haim Dreyfuss.
5) Fix use after free in iwl_mvm_d0i3_enable_tx(), from Eliad Peller.
6) JIT'ing of large BPF programs is broken on x86, from Alexei
Starovoitov.
7) EMAC driver ethtool register dump size is miscalculated, from Ivan
Mikhaylov.
8) Fix PHY initial link mode when autonegotiation is disabled in
amd-xgbe, from Tom Lendacky.
9) Fix NULL deref on SOCK_DEAD socket in AF_UNIX and CAIF protocols,
from Mark Salyzyn.
10) credit_bytes not initialized properly in xen-netback, from Ross
Lagerwall.
11) Fallback from MSI-X to INTx interrupts not handled properly in mlx4
driver, fix from Benjamin Poirier.
12) Perform ->attach() after binding dev->qdisc in packet scheduler,
otherwise we can crash. From Cong WANG.
13) Don't clobber data in sctp_v4_map_v6(). From Jason Gunthorpe.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (30 commits)
sctp: Fix mangled IPv4 addresses on a IPv6 listening socket
net_sched: invoke ->attach() after setting dev->qdisc
xen-netfront: properly destroy queues when removing device
mlx4_core: Fix fallback from MSI-X to INTx
xen/netback: Properly initialize credit_bytes
net: netxen: correct sysfs bin attribute return code
tools: bpf_jit_disasm: fix segfault on disabled debugging log output
unix/caif: sk_socket can disappear when state is unlocked
amd-xgbe-phy: Fix initial mode when autoneg is disabled
net: dp83640: fix improper double spin locking.
net: dp83640: reinforce locking rules.
net: dp83640: fix broken calibration routine.
net: stmmac: create one debugfs dir per net-device
net/ibm/emac: fix size of emac dump memory areas
x86: bpf_jit: fix compilation of large bpf programs
net: phy: bcm7xxx: Fix 7425 PHY ID and flags
iwlwifi: mvm: avoid use-after-free on iwl_mvm_d0i3_enable_tx()
iwlwifi: mvm: clean net-detect info if device was reset during suspend
iwlwifi: mvm: take the UCODE_DOWN reference when resuming
iwlwifi: mvm: BT Coex - duplicate the command if sent ASYNC
...
sctp_v4_map_v6 was subtly writing and reading from members
of a union in a way the clobbered data it needed to read before
it read it.
Zeroing the v6 flowinfo overwrites the v4 sin_addr with 0, meaning
that every place that calls sctp_v4_map_v6 gets ::ffff:0.0.0.0 as the
result.
Reorder things to guarantee correct behaviour no matter what the
union layout is.
This impacts user space clients that open an IPv6 SCTP socket and
receive IPv4 connections. Prior to 299ee user space would see a
sockaddr with AF_INET and a correct address, after 299ee the sockaddr
is AF_INET6, but the address is wrong.
Fixes: 299ee123e198 (sctp: Fixup v4mapped behaviour to comply with Sock API)
Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
While adding support for 7425 PHY in the 7xxx PHY driver, the ID that
was used was actually coming from an external PHY: a BCM5461x. Fix this
by using the proper ID for the internal 7425 PHY and set the
PHY_IS_INTERNAL flag, otherwise consumers of this PHY driver would not
be able to properly identify it as such.
Fixes: d068b02cfdfc2 ("net: phy: add BCM7425 and BCM7429 PHYs")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Petri Gynther <pgynther@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull timer fix from Thomas Gleixner:
"One more fix from the timer departement:
- Handle division of negative nanosecond values proper on 32bit.
A recent cleanup wrecked the sign handling of the dividend and
dropped the check for negative divisors"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
ktime: Fix ktime_divns to do signed division
Pull networking fixes from David Miller:
1) Don't leak ipvs->sysctl_tbl, from Tommi Rentala.
2) Fix neighbour table entry leak in rocker driver, from Ying Xue.
3) Do not emit bonding notifications for unregistered interfaces, from
Nicolas Dichtel.
4) Set ipv6 flow label properly when in TIME_WAIT state, from Florent
Fourcot.
5) Fix regression in ipv6 multicast filter test, from Henning Rogge.
6) do_replace() in various footables netfilter modules is missing a
check for 0 counters in the datastructure provided by the user. Fix
from Dave Jones, and found with trinity.
7) Fix RCU bug in packet scheduler classifier module unloads, from
Daniel Borkmann.
8) Avoid deadlock in tcp_get_info() by using u64_sync. From Eric
Dumzaet.
9) Input packet processing can race with inetdev_destroy() teardown,
fix potential OOPS in ip_error() by explicitly testing whether the
inetdev is still attached. From Eric W Biederman.
10) MLDv2 parser in bridge multicast code breaks too early while
parsing. Fix from Thadeu Lima de Souza Cascardo.
11) Asking for settings on non-zero PHYID doesn't work because we do not
import the command structure from the user and use the PHYID
provided there. Fix from Arun Parameswaran.
12) Fix UDP checksums with IPV6 RAW sockets, from Vlad Yasevich.
13) Missing NF_TABLES depends for TPROXY etc can cause build failures,
fix from Florian Westphal.
14) Fix netfilter conntrack to handle RFC5961 challenge ACKs properly,
from Jesper Dangaard Brouer.
15) If netlink autobind retry fails, we have to reset the sockets portid
back to zero. From Herbert Xu.
16) VXLAN netns exit code unregisters using wrong device, from John W
Linville.
17) Add some USB device IDs to ath3k and btusb bluetooth drivers, from
Dmitry Tunin and Wen-chien Jesse Sung.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (44 commits)
bridge: fix lockdep splat
net: core: 'ethtool' issue with querying phy settings
bridge: fix parsing of MLDv2 reports
ARM: zynq: DT: Use the zynq binding with macb
net: macb: Disable half duplex gigabit on Zynq
net: macb: Document zynq gem dt binding
ipv4: fill in table id when replacing a route
cdc_ncm: Fix tx_bytes statistics
ipv4: Avoid crashing in ip_error
tcp: fix a potential deadlock in tcp_get_info()
net: sched: fix call_rcu() race on classifier module unloads
net: phy: Make sure phy_start() always re-enables the phy interrupts
ipv6: fix ECMP route replacement
ipv6: do not delete previously existing ECMP routes if add fails
Revert "netfilter: bridge: query conntrack about skb dnat"
netfilter: ensure number of counters is >0 in do_replace()
netfilter: nfnetlink_{log,queue}: Register pernet in first place
tcp: don't over-send F-RTO probes
tcp: only undo on partial ACKs in CA_Loss
net/ipv6/udp: Fix ipv6 multicast socket filter regression
...
Pull block fixes from Jens Axboe:
"Three small fixes that have been picked up the last few weeks.
Specifically:
- Fix a memory corruption issue in NVMe with malignant user
constructed request. From Christoph.
- Kill (now) unused blk_queue_bio(), dm was changed to not need this
anymore. From Mike Snitzer.
- Always use blk_schedule_flush_plug() from the io_schedule() path
when flushing a plug, fixing a !TASK_RUNNING warning with md. From
Shaohua"
* 'for-linus' of git://git.kernel.dk/linux-block:
sched: always use blk_schedule_flush_plug in io_schedule_out
nvme: fix kernel memory corruption with short INQUIRY buffers
block: remove export for blk_queue_bio
Pablo Neira Ayuso says:
====================
Netfilter fixes for net
The following patchset contain Netfilter fixes for your net tree, they are:
1) Fix a race in nfnetlink_log and nfnetlink_queue that can lead to a crash.
This problem is due to wrong order in the per-net registration and netlink
socket events. Patch from Francesco Ruggeri.
2) Make sure that counters that userspace pass us are higher than 0 in all the
x_tables frontends. Discovered via Trinity, patch from Dave Jones.
3) Revert a patch for br_netfilter to rely on the conntrack status bits. This
breaks stateless IPv6 NAT transformations. Patch from Florian Westphal.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Taking socket spinlock in tcp_get_info() can deadlock, as
inet_diag_dump_icsk() holds the &hashinfo->ehash_locks[i],
while packet processing can use the reverse locking order.
We could avoid this locking for TCP_LISTEN states, but lockdep would
certainly get confused as all TCP sockets share same lockdep classes.
[ 523.722504] ======================================================
[ 523.728706] [ INFO: possible circular locking dependency detected ]
[ 523.734990] 4.1.0-dbg-DEV #1676 Not tainted
[ 523.739202] -------------------------------------------------------
[ 523.745474] ss/18032 is trying to acquire lock:
[ 523.750002] (slock-AF_INET){+.-...}, at: [<ffffffff81669d44>] tcp_get_info+0x2c4/0x360
[ 523.758129]
[ 523.758129] but task is already holding lock:
[ 523.763968] (&(&hashinfo->ehash_locks[i])->rlock){+.-...}, at: [<ffffffff816bcb75>] inet_diag_dump_icsk+0x1d5/0x6c0
[ 523.774661]
[ 523.774661] which lock already depends on the new lock.
[ 523.774661]
[ 523.782850]
[ 523.782850] the existing dependency chain (in reverse order) is:
[ 523.790326]
-> #1 (&(&hashinfo->ehash_locks[i])->rlock){+.-...}:
[ 523.796599] [<ffffffff811126bb>] lock_acquire+0xbb/0x270
[ 523.802565] [<ffffffff816f5868>] _raw_spin_lock+0x38/0x50
[ 523.808628] [<ffffffff81665af8>] __inet_hash_nolisten+0x78/0x110
[ 523.815273] [<ffffffff816819db>] tcp_v4_syn_recv_sock+0x24b/0x350
[ 523.822067] [<ffffffff81684d41>] tcp_check_req+0x3c1/0x500
[ 523.828199] [<ffffffff81682d09>] tcp_v4_do_rcv+0x239/0x3d0
[ 523.834331] [<ffffffff816842fe>] tcp_v4_rcv+0xa8e/0xc10
[ 523.840202] [<ffffffff81658fa3>] ip_local_deliver_finish+0x133/0x3e0
[ 523.847214] [<ffffffff81659a9a>] ip_local_deliver+0xaa/0xc0
[ 523.853440] [<ffffffff816593b8>] ip_rcv_finish+0x168/0x5c0
[ 523.859624] [<ffffffff81659db7>] ip_rcv+0x307/0x420
Lets use u64_sync infrastructure instead. As a bonus, 64bit
arches get optimized, as these are nop for them.
Fixes: 0df48c26d841 ("tcp: add tcpi_bytes_acked to tcp_info")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull HID fixes from Jiri Kosina:
"Bugfixes for HID subsystem that should go in 4.1. Important
highlights:
- the patch that extended support for HID++ protocol for TK820
touchpad turns out to be causing regressions due to firmware
issues; patch reverting back to basic support from Benjamin
Tissoires
- Wacom driver can oops for devices that report non-touch data on
touch interfaces. Fix from Ping Cheng
- gpiolib is not mandatory for i2c-hid, so the driver shouldn't fail
if gpiolib is not enabled. Fix from Mika Westerberg"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid:
HID: wacom: fix an Oops caused by wacom_wac_finger_count_touches
HID: usbhid: Add HID_QUIRK_NOGET for Aten DVI KVM switch
HID: hid-sensor-hub: Fix debug lock warning
Revert "HID: logitech-hidpp: support combo keyboard touchpad TK820"
HID: i2c-hid: Do not fail probing if gpiolib is not enabled
exception of a single locking fix in the core code. All driver fixes are
for code that was merged recently. The Samsung stuff is mostly fixes
around suspend/resume, the Qualcomm fixes are for invalid hardware
configuration data and the Silicon Labs patches are fixes following
their move away from platform_data to Device Tree.
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Merge tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux
Pull clk fixes from Michael Turquette:
"The first set of clk fixes for 4.1 are all driver bugs, with the
exception of a single locking fix in the core code.
All driver fixes are for code that was merged recently. The Samsung
stuff is mostly fixes around suspend/resume, the Qualcomm fixes are
for invalid hardware configuration data and the Silicon Labs patches
are fixes following their move away from platform_data to Device Tree"
* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
clk: si5351: Do not pass struct clk in platform_data
clk: si5351: Mention clock-names in the binding documentation
clk: add missing lock when call clk_core_enable in clk_set_parent
clk: exynos5420: Restore GATE_BUS_TOP on suspend
clk: qcom: Fix MSM8916 gfx3d_clk_src configuration
clk: qcom: Fix MSM8916 venus divider value
clk: exynos5433: Fix wrong PMS value of exynos5433_pll_rates
clk: exynos5433: Fix wrong parent clock of sclk_apollo clock
clk: exynos5433: Fix CLK_PCLK_MONOTONIC_CNT clk register assignment
clk: exynos5433: Fix wrong offset of PCLK_MSCL_SECURE_SMMU_JPEG
clk: Use CONFIG_ARCH_EXYNOS instead of CONFIG_ARCH_EXYNOS5433
This reverts commit c055d5b03bb4cb69d349d787c9787c0383abd8b2.
There are two issues:
'dnat_took_place' made me think that this is related to
-j DNAT/MASQUERADE.
But thats only one part of the story. This is also relevant for SNAT
when we undo snat translation in reverse/reply direction.
Furthermore, I originally wanted to do this mainly to avoid
storing ipv6 addresses once we make DNAT/REDIRECT work
for ipv6 on bridges.
However, I forgot about SNPT/DNPT which is stateless.
So we can't escape storing address for ipv6 anyway. Might as
well do it for ipv4 too.
Reported-and-tested-by: Bernhard Thaler <bernhard.thaler@wvnet.at>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
A non-percpu VIRQ (e.g., VIRQ_CONSOLE) may be freed on a different
VCPU than it is bound to. This can result in a race between
handle_percpu_irq() and removing the action in __free_irq() because
handle_percpu_irq() does not take desc->lock. The interrupt handler
sees a NULL action and oopses.
Only use the percpu chip/handler for per-CPU VIRQs (like VIRQ_TIMER).
# cat /proc/interrupts | grep virq
40: 87246 0 xen-percpu-virq timer0
44: 0 0 xen-percpu-virq debug0
47: 0 20995 xen-percpu-virq timer1
51: 0 0 xen-percpu-virq debug1
69: 0 0 xen-dyn-virq xen-pcpu
74: 0 0 xen-dyn-virq mce
75: 29 0 xen-dyn-virq hvc_console
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Cc: <stable@vger.kernel.org>
tcp_illinois and upcoming tcp_cdg require 64bit alignment of
icsk_ca_priv
x86 does not care, but other architectures might.
Fixes: 05cbc0db03e82 ("ipv4: Create probe timer for tcp PMTU as per RFC4821")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Fan Du <fan.du@intel.com>
Acked-by: Fan Du <fan.du@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently people use TASK_INTERRUPTIBLE to idle kthreads and wait for
'work' because TASK_UNINTERRUPTIBLE contributes to the loadavg. Having
all idle kthreads contribute to the loadavg is somewhat silly.
Now mostly this works OK, because kthreads have all their signals
masked. However there's a few sites where this is causing problems and
TASK_UNINTERRUPTIBLE should be used, except for that loadavg issue.
This patch adds TASK_NOLOAD which, when combined with
TASK_UNINTERRUPTIBLE avoids the loadavg accounting.
As most of imagined usage sites are loops where a thread wants to
idle, waiting for work, a helper TASK_IDLE is introduced.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Julian Anastasov <ja@ssi.bg>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: NeilBrown <neilb@suse.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Introduce faulthandler_disabled() and use it to check for irq context and
disabled pagefaults (via pagefault_disable()) in the pagefault handlers.
Please note that we keep the in_atomic() checks in place - to detect
whether in irq context (in which case preemption is always properly
disabled).
In contrast, preempt_disable() should never be used to disable pagefaults.
With !CONFIG_PREEMPT_COUNT, preempt_disable() doesn't modify the preempt
counter, and therefore the result of in_atomic() differs.
We validate that condition by using might_fault() checks when calling
might_sleep().
Therefore, add a comment to faulthandler_disabled(), describing why this
is needed.
faulthandler_disabled() and pagefault_disable() are defined in
linux/uaccess.h, so let's properly add that include to all relevant files.
This patch is based on a patch from Thomas Gleixner.
Reviewed-and-tested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: David.Laight@ACULAB.COM
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: airlied@linux.ie
Cc: akpm@linux-foundation.org
Cc: benh@kernel.crashing.org
Cc: bigeasy@linutronix.de
Cc: borntraeger@de.ibm.com
Cc: daniel.vetter@intel.com
Cc: heiko.carstens@de.ibm.com
Cc: herbert@gondor.apana.org.au
Cc: hocko@suse.cz
Cc: hughd@google.com
Cc: mst@redhat.com
Cc: paulus@samba.org
Cc: ralf@linux-mips.org
Cc: schwidefsky@de.ibm.com
Cc: yang.shi@windriver.com
Link: http://lkml.kernel.org/r/1431359540-32227-7-git-send-email-dahi@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commit 662bbcb2747c ("mm, sched: Allow uaccess in atomic with
pagefault_disable()") removed might_sleep() checks for all user access
code (that uses might_fault()).
The reason was to disable wrong "sleep in atomic" warnings in the
following scenario:
pagefault_disable()
rc = copy_to_user(...)
pagefault_enable()
Which is valid, as pagefault_disable() increments the preempt counter
and therefore disables the pagefault handler. copy_to_user() will not
sleep and return an error code if a page is not available.
However, as all might_sleep() checks are removed,
CONFIG_DEBUG_ATOMIC_SLEEP would no longer detect the following scenario:
spin_lock(&lock);
rc = copy_to_user(...)
spin_unlock(&lock)
If the kernel is compiled with preemption turned on, preempt_disable()
will make in_atomic() detect disabled preemption. The fault handler would
correctly never sleep on user access.
However, with preemption turned off, preempt_disable() is usually a NOP
(with !CONFIG_PREEMPT_COUNT), therefore in_atomic() will not be able to
detect disabled preemption nor disabled pagefaults. The fault handler
could sleep.
We really want to enable CONFIG_DEBUG_ATOMIC_SLEEP checks for user access
functions again, otherwise we can end up with horrible deadlocks.
Root of all evil is that pagefault_disable() acts almost as
preempt_disable(), depending on preemption being turned on/off.
As we now have pagefault_disabled(), we can use it to distinguish
whether user acces functions might sleep.
Convert might_fault() into a makro that calls __might_fault(), to
allow proper file + line messages in case of a might_sleep() warning.
Reviewed-and-tested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: David.Laight@ACULAB.COM
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: airlied@linux.ie
Cc: akpm@linux-foundation.org
Cc: benh@kernel.crashing.org
Cc: bigeasy@linutronix.de
Cc: borntraeger@de.ibm.com
Cc: daniel.vetter@intel.com
Cc: heiko.carstens@de.ibm.com
Cc: herbert@gondor.apana.org.au
Cc: hocko@suse.cz
Cc: hughd@google.com
Cc: mst@redhat.com
Cc: paulus@samba.org
Cc: ralf@linux-mips.org
Cc: schwidefsky@de.ibm.com
Cc: yang.shi@windriver.com
Link: http://lkml.kernel.org/r/1431359540-32227-3-git-send-email-dahi@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
__schedule() disables preemption and some of its callers
(the preempt_schedule*() family) also set PREEMPT_ACTIVE.
So we have two preempt_count() modifications that could be performed
at once.
Lets remove the preemption disablement from __schedule() and pull
this responsibility to its callers in order to optimize preempt_count()
operations in a single place.
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1431441711-29753-5-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
"CHECK" suggests it's only used as a comparison mask. But now it's used
further as a config-conditional preempt disabler offset. Lets
disambiguate this name.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1431441711-29753-4-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Adjust a few comments, and further integrate a few definitions after
the dumb headers copy.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1431441711-29753-3-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
preempt_mask.h defines all the preempt_count semantics and related
symbols: preempt, softirq, hardirq, nmi, preempt active, need resched,
etc...
preempt.h defines the accessors and mutators of preempt_count.
But there is a messy dependency game around those two header files:
* preempt_mask.h includes preempt.h in order to access preempt_count()
* preempt_mask.h defines all preempt_count semantic and symbols
except PREEMPT_NEED_RESCHED that is needed by asm/preempt.h
Thus we need to define it from preempt.h, right before including
asm/preempt.h, instead of defining it to preempt_mask.h with the
other preempt_count symbols. Therefore the preempt_count semantics
happen to be spread out.
* We plan to introduce preempt_active_[enter,exit]() to consolidate
preempt_schedule*() code. But we'll need to access both preempt_count
mutators (preempt_count_add()) and preempt_count symbols
(PREEMPT_ACTIVE, PREEMPT_OFFSET). The usual place to define preempt
operations is in preempt.h but then we'll need symbols in
preempt_mask.h which already includes preempt.h. So we end up with
a ressource circle dependency.
Lets merge preempt_mask.h into preempt.h to solve these dependency issues.
This way we gather semantic symbols and operation definition of
preempt_count in a single file.
This is a dumb copy-paste merge. Further merge re-arrangments are
performed in a subsequent patch to ease review.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1431441711-29753-2-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
