Paul E. McKenney [Wed, 22 Nov 2017 04:19:17 +0000 (20:19 -0800)]
torture: Eliminate torture_runnable and perf_runnable
The purpose of torture_runnable is to allow rcutorture and locktorture
to be started and stopped via sysfs when they are built into the kernel
(as in not compiled as loadable modules). However, the 0444 permissions
for both instances of torture_runnable prevent this use case from ever
being put into practice. Given that there have been no complaints
about this deficiency, it is reasonable to conclude that no one actually
makes use of this sysfs capability. The perf_runnable module parameter
for rcuperf is in the same situation.
This commit therefore removes both torture_runnable instances as well
as perf_runnable.
Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Tue, 21 Nov 2017 23:01:02 +0000 (15:01 -0800)]
torture: Make stutter less vulnerable to compilers and races
The stutter_wait() function repeatedly fetched stutter_pause_test, and
should really just fetch it once on each pass. The races should be
harmless, but why have the races? Also, the whole point of the value
"2" for stutter_pause_test is to get everyone to start at very nearly
the same time, but the value "2" was the first jiffy of the stutter
rather than the last jiffy of the stutter.
This commit rearranges the code to be more sensible.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Davidlohr Bueso [Mon, 15 May 2017 09:07:23 +0000 (02:07 -0700)]
locking/locktorture: Fix num reader/writer corner cases
Things can explode for locktorture if the user does combinations
of nwriters_stress=0 nreaders_stress=0. Fix this by not assuming
we always want to torture writer threads.
Reported-by: Jeremy Linton <jeremy.linton@arm.com> Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Jeremy Linton <jeremy.linton@arm.com> Tested-by: Jeremy Linton <jeremy.linton@arm.com>
Paul E. McKenney [Tue, 7 Nov 2017 22:10:03 +0000 (14:10 -0800)]
torture: Place all torture-test modules in one MAINTAINERS group
There is some confusion about where patches to kernel/torture.c
and kernel/locking/locktorture.c should be sent. This commit
therefore updates MAINTAINERS appropriately.
Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Check for build-directory existence and write permissions are provided in
both 'kvm-test-1-run.sh' an 'kvm-build.sh'. Because the 'kvm-build.sh'
is dependent on 'kvm-test-1-run.sh' ('kvm-build.sh' uses variables that
defined from its caller.), these checks are unnecessarily duplicated.
This commit therefore removes the check in from the 'kvm-build.sh' script.
Signed-off-by: SeongJae Park <sj38.park@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
SeongJae Park [Fri, 3 Nov 2017 10:17:28 +0000 (19:17 +0900)]
rcutorture: Simplify functions.sh include path
Inclusions of 'functions.sh' from 'kvm-test-1-run.sh' and
'kvm-recheck*.sh' use its absolute path. Because the directory containing
'functions.sh' is already in PATH, the full path is unnecessary. This
commit therefore simplifies the inclusions to use the short relative path.
Signed-off-by: SeongJae Park <sj38.park@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
SeongJae Park [Fri, 3 Nov 2017 10:17:27 +0000 (19:17 +0900)]
rcutorture: Simplify logging
Both the 'kvm.sh' and 'kvm-test-1-run.sh' scripts log messages by printing
the message to 'stdout' and then also printing it into the log file.
Generation of the message thus occurs twice, once for 'stdout' and once
for the log file. Moreover, many of the messages contain 'date' output,
which results in date being invoked twice (once for stdout print, once
for log file write). As a result, the date information in stdout and
log file can differ, which could cause confusion.
This commit therefore simplifies the logging procedure by using 'tee'.
Signed-off-by: SeongJae Park <sj38.park@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
SeongJae Park [Fri, 3 Nov 2017 10:17:25 +0000 (19:17 +0900)]
rcutorture/kvm-recheck-*: Improve result directory readability check
The kvm-recheck-(lock|rcu|rcuperf).sh scripts check whether the
user-specified results directory exists. If not, it prints out error
message that says the specified directory is unreadable. To make the
message more precise, this commit adds a readability check.
Fixes: 2193e1604eac ("rcutorture: Abstract kvm-recheck.sh") Signed-off-by: SeongJae Park <sj38.park@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
SeongJae Park [Fri, 3 Nov 2017 10:17:24 +0000 (19:17 +0900)]
rcutorture/kvm.sh: Support execution from any directory
The 'kvm.sh' rcutorture script requires that it be invoked from the top
of Linux-kernel source tree. It is just a subtle restriction, but users
using it for the first time could forget the restriction and be confused.
Moreover, it makes commands a little longer, which can be frustrating.
This commit therefore lets users invoke the script from any location.
Signed-off-by: SeongJae Park <sj38.park@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
SeongJae Park [Fri, 3 Nov 2017 10:17:23 +0000 (19:17 +0900)]
rcutorture/kvm.sh: Use consistent help text for --qemu-args
The '--qemu-args' option's help text is wrongly copied from '--qemu-cmd'
option and its argument type description message format is inconsistent
with other arguments. This commit fixes the usage and type messages to
be consistent with others.
Fixes: e9ce640001c6 ("rcutorture: Add --qemu-args argument to kvm.sh") Signed-off-by: SeongJae Park <sj38.park@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
SeongJae Park [Fri, 3 Nov 2017 10:17:21 +0000 (19:17 +0900)]
rcutorture: Remove unused script, config2frag.sh
The 'config2frag.sh' script is not used, so this commit removes it.
Fixes: c87b9c601ac8 ("rcutorture: Add KVM-based test framework") Signed-off-by: SeongJae Park <sj38.park@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The 'configinit.sh' script checks the format of optional argument for the
build directory, printing an error message if the format is not valid.
However, the error message uses the wrong variable, indicating an empty
string even though the user entered a non-empty (but erroneous) string.
This commit fixes the script to use the correct variable.
Fixes: c87b9c601ac8 ("rcutorture: Add KVM-based test framework") Signed-off-by: SeongJae Park <sj38.park@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Mon, 16 Oct 2017 18:23:42 +0000 (11:23 -0700)]
rcutorture: Preempt RCU-preempt readers more vigorously
This commit attempts to make a very rare rcutorture failure happen
more often by increasing the fraction of RCU-preempt read-side critical
sections that are preempted.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Mon, 16 Oct 2017 18:05:03 +0000 (11:05 -0700)]
torture: Reduce #ifdefs for preempt_schedule()
This commit adds a torture_preempt_schedule() that is nothingness
in !PREEMPT builds and is preempt_schedule() otherwise. Then
torture_preempt_schedule() is used to eliminate several ugly #ifdefs,
both in rcutorture and in locktorture.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Rakib Mullick [Fri, 17 Nov 2017 15:40:15 +0000 (21:40 +0600)]
rcu: Remove have_rcu_nocb_mask from tree_plugin.h
Currently have_rcu_nocb_mask is used to avoid double allocation of
rcu_nocb_mask during boot up. Due to different representation of
cpumask_var_t on different kernel config CPUMASK=y(or n) it was okay.
But now we have a helper cpumask_available(), which can be utilized
to check whether rcu_nocb_mask has been allocated or not without using
a variable.
This commit therefore adds a comment that states that this warning
usually triggers in response to a double call_rcu(), which is sort
of like a double free. The comment also suggests building with
CONFIG_DEBUG_OBJECTS_RCU_HEAD=y to track down the double call_rcu().
Reported-by: David Howells <dhowells@redhat.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Steven Rostedt (VMware) [Thu, 12 Oct 2017 22:16:41 +0000 (18:16 -0400)]
tracing, rcu: Hide trace event rcu_nocb_wake when not used
The trace event rcu_nocb_wake is only used when CONFIG_RCU_NOCB_CPU is
defined. But the trace event is defined regardless. As defined trace
events take up memory, it is a waste to have it defined when not used.
Surround the trace event with an #ifdef to have it only defined when it
is used.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Because READ_ONCE() now implies read_barrier_depends(), the
read_barrier_depends() in next_desc() is now redundant. This commit
therefore removes it and the related comments.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: <kvm@vger.kernel.org> Cc: <virtualization@lists.linux-foundation.org> Cc: <netdev@vger.kernel.org>
Paul E. McKenney [Mon, 27 Nov 2017 17:37:35 +0000 (09:37 -0800)]
checkpatch: Add warnings for {smp_,}read_barrier_depends()
Now that both smp_read_barrier_depends() and read_barrier_depends()
are being de-emphasized, warn if any are added.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Andy Whitcroft <apw@canonical.com> Cc: Joe Perches <joe@perches.com>
[ paulmck: Skipped checking files and handled whitespace per Joe Perches. ]
Paul E. McKenney [Mon, 27 Nov 2017 17:23:24 +0000 (09:23 -0800)]
genetlink: Remove smp_read_barrier_depends() from comment
Now that smp_read_barrier_depends() has been de-emphasized, the less
said about it, the better.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now that READ_ONCE() implies smp_read_barrier_depends(), the
__cleanup() and ioat_abort_descs() functions no longer need their
smp_read_barrier_depends() calls, which this commit removes.
It is actually not entirely clear why this driver ever included
smp_read_barrier_depends() given that it appears to be x86-only and
given that smp_read_barrier_depends() has no effect whatsoever except
on DEC Alpha.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Vinod Koul <vinod.koul@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: <dmaengine@vger.kernel.org>
This commit therefore makes Infiniband depend on !ALPHA and removes
the now-ineffective invocations of smp_read_barrier_depends() from
the InfiniBand driver.
Please note that this patch should not be construed as my saying that
InfiniBand's memory ordering is correct, but rather that this patch does
not in any way affect InfiniBand's correctness. In other words, the
result of applying this patch is bug-for-bug compatible with the original.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Doug Ledford <dledford@redhat.com> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Cc: Michael Cree <mcree@orcon.net.nz> Cc: Andrea Parri <parri.andrea@gmail.com> Cc: <linux-rdma@vger.kernel.org> Cc: <linux-alpha@vger.kernel.org>
[ paulmck: Removed drivers/dma/ioat/dma.c per Jason Gunthorpe's feedback. ] Acked-by: Jason Gunthorpe <jgg@mellanox.com>
Now that the associative-array library properly heads dependency chains,
the various smp_read_barrier_depends() calls in security/keys/keyring.c
are no longer needed. This commit therefore removes them.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: David Howells <dhowells@redhat.com> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: <keyrings@vger.kernel.org> Cc: <linux-security-module@vger.kernel.org> Reviewed-by: James Morris <james.l.morris@oracle.com>
READ_ONCE() now implies smp_read_barrier_depends(), which means that
the instances in arpt_do_table(), ipt_do_table(), and ip6t_do_table()
are now redundant. This commit removes them and adjusts the comments.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Pablo Neira Ayuso <pablo@netfilter.org> Cc: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu> Cc: Florian Westphal <fw@strlen.de> Cc: "David S. Miller" <davem@davemloft.net> Cc: <netfilter-devel@vger.kernel.org> Cc: <coreteam@netfilter.org> Cc: <netdev@vger.kernel.org>
Because READ_ONCE() now implies smp_read_barrier_depends(), the
smp_read_barrier_depends() in get_ksm_page() is now redundant.
This commit removes it and updates the comments.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Cc: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com> Cc: <linux-mm@kvack.org>
Now that smp_read_barrier_depends() is implied by READ_ONCE(), the several
smp_read_barrier_depends() calls may be removed from lib/assoc_array.c.
This commit makes this change and marks the READ_ONCE() calls that head
address dependencies.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Alexander Kuleshov <kuleshovmail@gmail.com> Cc: David Howells <dhowells@redhat.com>
Paul E. McKenney [Mon, 9 Oct 2017 18:30:11 +0000 (11:30 -0700)]
tracepoint: Remove smp_read_barrier_depends() from comment
The comment in tracepoint_add_func() mentions smp_read_barrier_depends(),
whose use should be quite restricted. This commit updates the comment
to instead mention the smp_store_release() and rcu_dereference_sched()
that the current code actually uses.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Paul E. McKenney [Mon, 9 Oct 2017 18:22:50 +0000 (11:22 -0700)]
locking: Remove smp_read_barrier_depends() from queued_spin_lock_slowpath()
Queued spinlocks are not used by DEC Alpha, and furthermore operations
such as READ_ONCE() and release/relaxed RMW atomics are being changed
to imply smp_read_barrier_depends(). This commit therefore removes the
now-redundant smp_read_barrier_depends() from queued_spin_lock_slowpath(),
and adjusts the comments accordingly.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@redhat.com>
Now that READ_ONCE() implies smp_read_barrier_depends(), the
get_xol_area() and get_trampoline_vaddr() no longer need their
smp_read_barrier_depends() calls, which this commit removes.
While we are here, convert the corresponding smp_wmb() to an
smp_store_release().
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Paul E. McKenney [Mon, 9 Oct 2017 17:20:44 +0000 (10:20 -0700)]
percpu: READ_ONCE() now implies smp_read_barrier_depends()
Because READ_ONCE() now implies smp_read_barrier_depends(), this commit
removes the now-redundant smp_read_barrier_depends() following the
READ_ONCE() in __ref_is_percpu().
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Tejun Heo <tj@kernel.org> Cc: Christoph Lameter <cl@linux.com>
Paul E. McKenney [Mon, 9 Oct 2017 17:04:27 +0000 (10:04 -0700)]
fs/dcache: Use release-acquire for name/length update
The code in __d_alloc() carefully orders filling in the NUL character
of the name (and the length, hash, and the name itself) with assigning
of the name itself. However, prepend_name() does not order the accesses
to the ->name and ->len fields, other than on TSO systems. This commit
therefore replaces prepend_name()'s READ_ONCE() of ->name with an
smp_load_acquire(), which orders against the subsequent READ_ONCE() of
->len. Because READ_ONCE() now incorporates smp_read_barrier_depends(),
prepend_name()'s smp_read_barrier_depends() is removed. Finally,
to save a line, the smp_wmb()/store pair in __d_alloc() is replaced
by smp_store_release().
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: <linux-fsdevel@vger.kernel.org>
The __qed_spq_block() function expects an smp_read_barrier_depends()
to order a prior READ_ONCE() against a later load that does not depend
on the prior READ_ONCE(), an expectation that can fail to be met.
This commit therefore replaces the READ_ONCE() with smp_load_acquire()
and removes the smp_read_barrier_depends().
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ariel Elior <Ariel.Elior@cavium.com> Cc: <everest-linux-l2@cavium.com> Cc: <netdev@vger.kernel.org>
Paul E. McKenney [Mon, 9 Oct 2017 16:17:49 +0000 (09:17 -0700)]
mn10300: READ_ONCE() now implies smp_read_barrier_depends()
Given that READ_ONCE() now implies smp_read_barrier_depends(),
there is no need for the open-coded smp_read_barrier_depends() in
mn10300_serial_receive_interrupt() and mn10300_serial_poll_get_char().
This commit therefore removes them, but replaces them with comments
calling out that carrying dependencies through non-pointers is quite
dangerous. Compilers simply know too much about integers.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: David Howells <dhowells@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: <linux-am33-list@redhat.com>
Paul E. McKenney [Mon, 9 Oct 2017 16:15:21 +0000 (09:15 -0700)]
doc: READ_ONCE() now implies smp_barrier_depends()
This commit updates an example in memory-barriers.txt to account for
the fact that READ_ONCE() now implies smp_barrier_depends().
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ paulmck: Added MEMORY_BARRIER instructions from DEC Alpha from
READ_ONCE(), per David Howells's feedback. ]
Paul E. McKenney [Sun, 5 Nov 2017 13:51:43 +0000 (05:51 -0800)]
rcu: Account for rcu_all_qs() in cond_resched()
If cond_resched() returns false, then it has already invoked
rcu_all_qs(). This is also invoked (now redundantly) by
rcu_note_voluntary_context_switch(). This commit therefore changes
cond_resched_rcu_qs() to invoke rcu_note_voluntary_context_switch_lite()
instead of rcu_note_voluntary_context_switch() to avoid the redundant
invocation of rcu_all_qs().
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Tue, 24 Oct 2017 15:42:41 +0000 (08:42 -0700)]
doc: Eliminate cond_resched_rcu_qs() in favor of cond_resched()
Now that cond_resched() also provides RCU quiescent states when
needed, it can be used in place of cond_resched_rcu_qs(). This
commit therefore documents this change.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Tue, 24 Oct 2017 15:39:34 +0000 (08:39 -0700)]
fs: Eliminate cond_resched_rcu_qs() in favor of cond_resched()
Now that cond_resched() also provides RCU quiescent states when
needed, it can be used in place of cond_resched_rcu_qs(). This
commit therefore makes this change.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: <linux-fsdevel@vger.kernel.org>
Paul E. McKenney [Tue, 24 Oct 2017 15:31:12 +0000 (08:31 -0700)]
softirq: Eliminate cond_resched_rcu_qs() in favor of cond_resched()
Now that cond_resched() also provides RCU quiescent states when
needed, it can be used in place of cond_resched_rcu_qs(). This
commit therefore makes this change.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: NeilBrown <neilb@suse.com> Cc: Ingo Molnar <mingo@kernel.org>
Paul E. McKenney [Tue, 24 Oct 2017 15:26:32 +0000 (08:26 -0700)]
trace: Eliminate cond_resched_rcu_qs() in favor of cond_resched()
Now that cond_resched() also provides RCU quiescent states when
needed, it can be used in place of cond_resched_rcu_qs(). This
commit therefore makes this change.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Ingo Molnar <mingo@redhat.com>
Paul E. McKenney [Tue, 24 Oct 2017 15:25:02 +0000 (08:25 -0700)]
workqueue: Eliminate cond_resched_rcu_qs() in favor of cond_resched()
Now that cond_resched() also provides RCU quiescent states when
needed, it can be used in place of cond_resched_rcu_qs(). This
commit therefore makes this change.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Tejun Heo <tj@kernel.org> Reviewed-by: Lai Jiangshan <jiangshanlai@gmail.com>
Paul E. McKenney [Tue, 24 Oct 2017 15:22:18 +0000 (08:22 -0700)]
mm: Eliminate cond_resched_rcu_qs() in favor of cond_resched()
Now that cond_resched() also provides RCU quiescent states when
needed, it can be used in place of cond_resched_rcu_qs(). This
commit therefore makes this change.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Vlastimil Babka <vbabka@suse.cz>
Paul E. McKenney [Tue, 24 Oct 2017 13:48:39 +0000 (06:48 -0700)]
netfilter: Eliminate cond_resched_rcu_qs() in favor of cond_resched()
Now that cond_resched() also provides RCU quiescent states when
needed, it can be used in place of cond_resched_rcu_qs(). This
commit therefore makes this change.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Pablo Neira Ayuso <pablo@netfilter.org> Cc: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu> Cc: Florian Westphal <fw@strlen.de> Cc: "David S. Miller" <davem@davemloft.net> Cc: <netfilter-devel@vger.kernel.org>
Paul E. McKenney [Sat, 14 Oct 2017 00:00:18 +0000 (17:00 -0700)]
sched: Stop switched_to_rt() from sending IPIs to offline CPUs
The rcutorture test suite occasionally provokes a splat due to invoking
rt_mutex_lock() which needs to boost the priority of a task currently
sitting on a runqueue that belongs to an offline CPU:
But the target task's priority has already been adjusted, so the only
purpose of switched_to_rt() invoking resched_curr() is to wake up the
CPU running some task that needs to be preempted by the boosted task.
But the CPU is offline, which presumably means that the task must be
migrated to some other CPU, and that this other CPU will undertake any
needed preemption at the time of migration. Because the runqueue lock
is held when resched_curr() is invoked, we know that the boosted task
cannot go anywhere, so it is not necessary to invoke resched_curr()
in this particular case.
This commit therefore makes switched_to_rt() refrain from invoking
resched_curr() when the target CPU is offline.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org>
This splat cannot be generated by expedited grace periods because they
always invoke resched_cpu() on the current CPU, which is good because
expedited grace periods require that resched_cpu() unconditionally
succeed. However, other parts of RCU can tolerate resched_cpu() acting
as a no-op, at least as long as it doesn't happen too often.
This commit therefore makes resched_cpu() invoke resched_curr() only if
the CPU is either online or is the current CPU.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org>
Paul E. McKenney [Thu, 12 Oct 2017 18:00:33 +0000 (11:00 -0700)]
torture: Prepare scripting for shift from %p to %pK
Because %p prints "(null)" and %pK prints "0000000000000000" or (on
32-bit systems) "00000000", this commit adjusts torture-test scripting
accordingly.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Wed, 4 Oct 2017 18:23:10 +0000 (11:23 -0700)]
torture: Suppress CPU stall warnings during shutdown ftrace dump
The torture_shutdown() function directly invokes ftrace_dump(), which
can result in RCU CPU stall warnings when the ftrace buffer is large,
which it usually is. This commit therefore invoks rcu_ftrace_dump()
in place of ftrace_dump(), suppressing RCU CPU stall warnings during
this time.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Tue, 10 Oct 2017 20:52:30 +0000 (13:52 -0700)]
srcu: Prohibit call_srcu() use under raw spinlocks
Invoking queue_delayed_work() while holding a raw spinlock is forbidden
in -rt kernels, which is exactly what __call_srcu() does, indirectly via
srcu_funnel_gp_start(). This commit therefore downgrades Tree SRCU's
locking from raw to non-raw spinlocks, which works because call_srcu()
is not ever called while holding a raw spinlock.
Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Steven Rostedt (VMware) [Thu, 12 Oct 2017 22:12:57 +0000 (18:12 -0400)]
tracing, rcu: Remove no longer used trace event rcu_prep_idle
Commit c0f4dfd4f90 ("rcu: Make RCU_FAST_NO_HZ take advantage of
numbered callbacks") removed the only instances of trace_rcu_prep_idle,
but did not remove the TRACE_EVENT() that creates it. As defined trace
events take up memory within the kernel even when they are not used,
this is a waste of space. Remove the obsolete event.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The code that checks for non-idle non-nohz_idle-usermode tasks invoking
rcu_eqs_enter() and rcu_eqs_exit() prints a considerable quantity of
helpful information. However, these checks fire rarely, so the extra
complexity is no longer worth it. This commit therefore replaces this
debug code with simple WARN_ON_ONCE() statements.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Thu, 5 Oct 2017 23:56:26 +0000 (16:56 -0700)]
rcu: Fold rcu_eqs_exit_common() into rcu_eqs_exit()
There is now only one call to rcu_eqs_exit_common() and there is no other
reason to keep it separate. This commit therefore inlines it into its
sole call site, saving a few lines of code in the process.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Thu, 5 Oct 2017 23:37:03 +0000 (16:37 -0700)]
rcu: Fold rcu_eqs_enter_common() into rcu_eqs_enter()
There is now only one call to rcu_eqs_enter_common() and there is no other
reason to keep it separate. This commit therefore inlines it into its
sole call site, saving a few lines of code in the process.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Thu, 5 Oct 2017 22:03:10 +0000 (15:03 -0700)]
rcu: Avoid ->dynticks_nesting store tearing
Although ->dynticks_nesting is updated only by process level, it is
accessed from hardirq to check for interrupt-from-idle quiescent states.
Store tearing is thus possible, so this commit applies WRITE_ONCE()
to ->dynticks_nesting stores.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Wed, 4 Oct 2017 22:55:16 +0000 (15:55 -0700)]
rcu: Shrink ->dynticks_{nmi_,}nesting from long long to long
Because the ->dynticks_nesting field now only contains the process-based
nesting level instead of a value encoding both the process nesting level
and the irq "nesting" level, we no longer need a long long, even on
32-bit systems. This commit therefore changes both the ->dynticks_nesting
and ->dynticks_nmi_nesting fields to long.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Tue, 3 Oct 2017 23:51:47 +0000 (16:51 -0700)]
rcu: Eliminate rcu_irq_enter_disabled()
Now that the irq path uses the rcu_nmi_{enter,exit}() algorithm,
rcu_irq_enter() and rcu_irq_exit() may be used from any context. There is
thus no need for rcu_irq_enter_disabled() and for the checks using it.
This commit therefore eliminates rcu_irq_enter_disabled().
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Tue, 3 Oct 2017 21:43:40 +0000 (14:43 -0700)]
rcu: Make ->dynticks_nesting be a simple counter
Now that ->dynticks_nesting counts only process-level dyntick-idle
entry and exit, there is no need for the elaborate segmented counter
with its guard fields and overflow checking. This commit therefore
makes ->dynticks_nesting be a simple counter.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Tue, 3 Oct 2017 17:42:22 +0000 (10:42 -0700)]
rcu: Define rcu_irq_{enter,exit}() in terms of rcu_nmi_{enter,exit}()
RCU currently uses two different mechanisms for tracking irqs and NMIs.
This is unnecessary complexity: Given that NMIs can nest and given that
RCU's tracking handles such nesting, the NMI tracking mechanism can also
be used to track irqs. This commit therefore defines rcu_irq_enter()
in terms of rcu_nmi_enter() and rcu_irq_exit() in terms of rcu_nmi_exit().
Unfortunately, callers must still distinguish between the irq and NMI
functions because additional actions are taken when an irq interrupts
idle or nohz_full usermode execution, and these actions cannot always
be taken from NMI handlers.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Tue, 3 Oct 2017 15:28:04 +0000 (08:28 -0700)]
rcu: Clamp ->dynticks_nmi_nesting at eqs entry/exit
In preparation for merging dyntick-idle irq handling into the NMI
algorithm, clamp ->dynticks_nmi_nesting value to allow for interrupts
that enter but never leave and vice versa.
It is important that the clamping happen outside of the extended quiescent
state. Otherwise, there will be short windows where irqs and NMIs fail
to convince RCU to start watching.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Tue, 3 Oct 2017 02:45:10 +0000 (19:45 -0700)]
rcu: Reduce dyntick-idle state space
Both extended-quiescent-state entry and exit first update the nesting
counter and then adjust the dyntick-idle state. This means that there
are four states: (1) Both nesting and dyntick idle indicate idle,
(2) Nesting indicates idle but dyntick idle does not, (3) Nesting indicates
non-idle and dyntick idle does not, and (4) Both nesting and dyntick
idle indicate non-idle. This commit simplifies the state space by
eliminating #3, reversing the order of updates on exit from extended
quiescent state.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Mon, 2 Oct 2017 23:54:49 +0000 (16:54 -0700)]
rcu: Avoid ->dynticks_nmi_nesting store tearing
NMIs can nest, and store tearing could in theory happen on carries
from one byte to the next. This commit therefore adds the WRITE_ONCE()
macros preventing this.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Linus Torvalds [Sun, 26 Nov 2017 23:03:49 +0000 (15:03 -0800)]
Merge branch 'fixes' of git://git.armlinux.org.uk/~rmk/linux-arm
Pull ARM fixes from Russell King:
- LPAE fixes for kernel-readonly regions
- Fix for get_user_pages_fast on LPAE systems
- avoid tying decompressor to a particular platform if DEBUG_LL is
enabled
- BUG if we attempt to return to userspace but the to-be-restored PSR
value keeps us in privileged mode (defeating an issue that ftracetest
found)
* 'fixes' of git://git.armlinux.org.uk/~rmk/linux-arm:
ARM: BUG if jumping to usermode address in kernel mode
ARM: 8722/1: mm: make STRICT_KERNEL_RWX effective for LPAE
ARM: 8721/1: mm: dump: check hardware RO bit for LPAE
ARM: make decompressor debug output user selectable
ARM: fix get_user_pages_fast
Linus Torvalds [Sun, 26 Nov 2017 22:39:20 +0000 (14:39 -0800)]
Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Thomas Glexiner:
- unbreak the irq trigger type check for legacy platforms
- a handful fixes for ARM GIC v3/4 interrupt controllers
- a few trivial fixes all over the place
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq/matrix: Make - vs ?: Precedence explicit
irqchip/imgpdc: Use resource_size function on resource object
irqchip/qcom: Fix u32 comparison with value less than zero
irqchip/exiu: Fix return value check in exiu_init()
irqchip/gic-v3-its: Remove artificial dependency on PCI
irqchip/gic-v4: Add forward definition of struct irq_domain_ops
irqchip/gic-v3: pr_err() strings should end with newlines
irqchip/s3c24xx: pr_err() strings should end with newlines
irqchip/gic-v3: Fix ppi-partitions lookup
irqchip/gic-v4: Clear IRQ_DISABLE_UNLAZY again if mapping fails
genirq: Track whether the trigger type has been set
Linus Torvalds [Sun, 26 Nov 2017 22:11:54 +0000 (14:11 -0800)]
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull misc x86 fixes from Ingo Molnar:
- topology enumeration fixes
- KASAN fix
- two entry fixes (not yet the big series related to KASLR)
- remove obsolete code
- instruction decoder fix
- better /dev/mem sanity checks, hopefully working better this time
- pkeys fixes
- two ACPI fixes
- 5-level paging related fixes
- UMIP fixes that should make application visible faults more debuggable
- boot fix for weird virtualization environment
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
x86/decoder: Add new TEST instruction pattern
x86/PCI: Remove unused HyperTransport interrupt support
x86/umip: Fix insn_get_code_seg_params()'s return value
x86/boot/KASLR: Remove unused variable
x86/entry/64: Add missing irqflags tracing to native_load_gs_index()
x86/mm/kasan: Don't use vmemmap_populate() to initialize shadow
x86/entry/64: Fix entry_SYSCALL_64_after_hwframe() IRQ tracing
x86/pkeys/selftests: Fix protection keys write() warning
x86/pkeys/selftests: Rename 'si_pkey' to 'siginfo_pkey'
x86/mpx/selftests: Fix up weird arrays
x86/pkeys: Update documentation about availability
x86/umip: Print a warning into the syslog if UMIP-protected instructions are used
x86/smpboot: Fix __max_logical_packages estimate
x86/topology: Avoid wasting 128k for package id array
perf/x86/intel/uncore: Cache logical pkg id in uncore driver
x86/acpi: Reduce code duplication in mp_override_legacy_irq()
x86/acpi: Handle SCI interrupts above legacy space gracefully
x86/boot: Fix boot failure when SMP MP-table is based at 0
x86/mm: Limit mmap() of /dev/mem to valid physical addresses
x86/selftests: Add test for mapping placement for 5-level paging
...
Linus Torvalds [Sun, 26 Nov 2017 21:43:25 +0000 (13:43 -0800)]
Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
"Misc fixes: a documentation fix, a Sparse warning fix and a debugging
fix"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/debug: Fix task state recording/printout
sched/deadline: Don't use dubious signed bitfields
sched/deadline: Fix the description of runtime accounting in the documentation
Linus Torvalds [Sun, 26 Nov 2017 21:41:48 +0000 (13:41 -0800)]
Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
"Misc fixes: two PMU driver fixes and a memory leak fix"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Fix memory leak triggered by perf --namespace
perf/x86/intel/uncore: Add event constraint for BDX PCU
perf/x86/intel: Hide TSX events when RTM is not supported
Linus Torvalds [Sun, 26 Nov 2017 21:11:18 +0000 (13:11 -0800)]
Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull objtool fixes from Ingo Molnar:
"A handful of objtool fixes, most of them related to making the UAPI
header-syncing warnings easier to read and easier to act upon"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tools/headers: Sync objtool UAPI header
objtool: Fix cross-build
objtool: Move kernel headers/code sync check to a script
objtool: Move synced files to their original relative locations
objtool: Make unreachable annotation inline asms explicitly volatile
objtool: Add a comment for the unreachable annotation macros
Russell King [Fri, 24 Nov 2017 23:49:34 +0000 (23:49 +0000)]
ARM: BUG if jumping to usermode address in kernel mode
Detect if we are returning to usermode via the normal kernel exit paths
but the saved PSR value indicates that we are in kernel mode. This
could occur due to corrupted stack state, which has been observed with
"ftracetest".
This ensures that we catch the problem case before we get to user code.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Linus Torvalds [Sat, 25 Nov 2017 18:21:54 +0000 (08:21 -1000)]
Merge tag 'arc-4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc
Pull ARC updates from Vineet Gupta:
- more changes for HS48 cores: supporting MMUv5, detecting new
micro-arch gizmos
- axs10x platform wiring up reset driver merged in this cycle
- ARC perf driver optimizations
* tag 'arc-4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
ARC: perf: avoid vmalloc backed mmap
ARCv2: perf: optimize given that num counters <= 32
ARCv2: perf: tweak overflow interrupt
ARC: [plat-axs10x] DTS: Add reset controller node to manage ethernet reset
ARCv2: boot log: updates for HS48: dual-issue, ECC, Loop Buffer
ARCv2: Accomodate HS48 MMUv5 by relaxing MMU ver checking
ARC: [plat-axs10x] auto-select AXS101 or AXS103 given the ISA config
Linus Torvalds [Sat, 25 Nov 2017 18:06:30 +0000 (08:06 -1000)]
Merge tag 'kbuild-v4.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull more Kbuild updates from Masahiro Yamada:
- use 'pwd' instead of '/bin/pwd' for portability
- clean up Makefiles
- fix ld-option for clang
- fix malloc'ed data size in Kconfig
- fix parallel building along with coccicheck
- fix a minor issue of package building
- prompt to use "rpm-pkg" instead of "rpm"
- clean up *.i and *.lst patterns by "make clean"
* tag 'kbuild-v4.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kbuild: drop $(extra-y) from real-objs-y
kbuild: clean up *.i and *.lst patterns by make clean
kbuild: rpm: prompt to use "rpm-pkg" if "rpm" target is used
kbuild: pkg: use --transform option to prefix paths in tar
coccinelle: fix parallel build with CHECK=scripts/coccicheck
kconfig/symbol.c: use correct pointer type argument for sizeof
kbuild: Set KBUILD_CFLAGS before incl. arch Makefile
kbuild: remove all dummy assignments to obj-
kbuild: create built-in.o automatically if parent directory wants it
kbuild: /bin/pwd -> pwd
Linus Torvalds [Sat, 25 Nov 2017 17:58:25 +0000 (07:58 -1000)]
Merge tag 'afs-fixes-20171124' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
Pull AFS fixes from David Howells:
- Make AFS file locking work again.
- Don't write to a page that's being written out, but wait for it to
complete.
- Do d_drop() and d_add() in the right places.
- Put keys on error paths.
- Remove some redundant code.
* tag 'afs-fixes-20171124' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
afs: remove redundant assignment of dvnode to itself
afs: cell: Remove unnecessary code in afs_lookup_cell
afs: Fix signal handling in some file ops
afs: Fix some dentry handling in dir ops and missing key_puts
afs: Make afs_write_begin() avoid writing to a page that's being stored
afs: Fix file locking
Linus Torvalds [Sat, 25 Nov 2017 05:44:25 +0000 (19:44 -1000)]
Merge tag 'kvm-4.15-2' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Radim Krčmář:
"Trimmed second batch of KVM changes for Linux 4.15:
- GICv4 Support for KVM/ARM
- re-introduce support for CPUs without virtual NMI (cc stable) and
allow testing of KVM without virtual NMI on available CPUs
- fix long-standing performance issues with assigned devices on AMD
(cc stable)"
* tag 'kvm-4.15-2' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (30 commits)
kvm: vmx: Allow disabling virtual NMI support
kvm: vmx: Reinstate support for CPUs without virtual NMI
KVM: SVM: obey guest PAT
KVM: arm/arm64: Don't queue VLPIs on INV/INVALL
KVM: arm/arm64: Fix GICv4 ITS initialization issues
KVM: arm/arm64: GICv4: Theory of operations
KVM: arm/arm64: GICv4: Enable VLPI support
KVM: arm/arm64: GICv4: Prevent userspace from changing doorbell affinity
KVM: arm/arm64: GICv4: Prevent a VM using GICv4 from being saved
KVM: arm/arm64: GICv4: Enable virtual cpuif if VLPIs can be delivered
KVM: arm/arm64: GICv4: Hook vPE scheduling into vgic flush/sync
KVM: arm/arm64: GICv4: Use the doorbell interrupt as an unblocking source
KVM: arm/arm64: GICv4: Add doorbell interrupt handling
KVM: arm/arm64: GICv4: Use pending_last as a scheduling hint
KVM: arm/arm64: GICv4: Handle INVALL applied to a vPE
KVM: arm/arm64: GICv4: Propagate property updates to VLPIs
KVM: arm/arm64: GICv4: Handle MOVALL applied to a vPE
KVM: arm/arm64: GICv4: Handle CLEAR applied to a VLPI
KVM: arm/arm64: GICv4: Propagate affinity changes to the physical ITS
KVM: arm/arm64: GICv4: Unmap VLPI when freeing an LPI
...
Linus Torvalds [Sat, 25 Nov 2017 05:40:12 +0000 (19:40 -1000)]
Merge tag 'powerpc-4.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
"A small batch of fixes, about 50% tagged for stable and the rest for
recently merged code.
There's one more fix for the >128T handling on hash. Once a process
had requested a single mmap above 128T we would then always search
above 128T. The correct behaviour is to consider the hint address in
isolation for each mmap request.
Then a couple of fixes for the IMC PMU, a missing EXPORT_SYMBOL in
VAS, a fix for STRICT_KERNEL_RWX on 32-bit, and a fix to correctly
identify P9 DD2.1 but in code that is currently not used by default.
* tag 'powerpc-4.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/64s: Fix Power9 DD2.1 logic in DT CPU features
powerpc/perf: Fix IMC_MAX_PMU macro
powerpc/perf: Fix pmu_count to count only nest imc pmus
powerpc: Fix boot on BOOK3S_32 with CONFIG_STRICT_KERNEL_RWX
powerpc/perf/imc: Use cpu_to_node() not topology_physical_package_id()
powerpc/vas: Export chip_to_vas_id()
powerpc/64s/slice: Use addr limit when computing slice mask
Linus Torvalds [Sat, 25 Nov 2017 05:19:20 +0000 (19:19 -1000)]
Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
Pull SCSI target updates from Nicholas Bellinger:
"This series is predominantly bug-fixes, with a few small improvements
that have been outstanding over the last release cycle.
As usual, the associated bug-fixes have CC' tags for stable.
Also, things have been particularly quiet wrt new developments the
last months, with most folks continuing to focus on stability atop 4.x
stable kernels for their respective production configurations.
Also at this point, the stable trees have been synced up with
mainline. This will continue to be a priority, as production users
tend to run exclusively atop stable kernels, a few releases behind
mainline.
- Fix quiese during transport_write_pending_qf endless loop (nab)
- Avoid early CMD_T_PRE_EXECUTE failures during ABORT_TASK in 3.14+
(Don White + nab)"
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (35 commits)
tcmu: Add a missing unlock on an error path
tcmu: Fix some memory corruption
iscsi-target: Fix non-immediate TMR reference leak
iscsi-target: Make TASK_REASSIGN use proper se_cmd->cmd_kref
target: Avoid early CMD_T_PRE_EXECUTE failures during ABORT_TASK
target: Fix quiese during transport_write_pending_qf endless loop
target: Fix caw_sem leak in transport_generic_request_failure
target: Fix QUEUE_FULL + SCSI task attribute handling
iSCSI-target: Use common error handling code in iscsi_decode_text_input()
target/iscsi: Detect conn_cmd_list corruption early
target/iscsi: Fix a race condition in iscsit_add_reject_from_cmd()
target/iscsi: Modify iscsit_do_crypto_hash_buf() prototype
target/iscsi: Fix endianness in an error message
target/iscsi: Use min() in iscsit_dump_data_payload() instead of open-coding it
target/iscsi: Define OFFLOAD_BUF_SIZE once
target: Inline transport_put_cmd()
target: Suppress gcc 7 fallthrough warnings
target: Move a declaration of a global variable into a header file
tcmu: fix double se_cmd completion
target: return SAM_STAT_TASK_SET_FULL for TCM_OUT_OF_RESOURCES
...
Colin Ian King [Mon, 20 Nov 2017 13:58:20 +0000 (13:58 +0000)]
afs: remove redundant assignment of dvnode to itself
The assignment of dvnode to itself is redundant and can be removed.
Cleans up warning detected by cppcheck:
fs/afs/dir.c:975: (warning) Redundant assignment of 'dvnode' to itself.
Fixes: d2ddc776a458 ("afs: Overhaul volume and server record caching and fileserver rotation") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: David Howells <dhowells@redhat.com>
David Howells [Mon, 20 Nov 2017 22:41:00 +0000 (22:41 +0000)]
afs: Fix signal handling in some file ops
afs_mkdir(), afs_create(), afs_link() and afs_symlink() all need to drop
the target dentry if a signal causes the operation to be killed immediately
before we try to contact the server.
Signed-off-by: David Howells <dhowells@redhat.com>
David Howells [Mon, 20 Nov 2017 23:04:08 +0000 (23:04 +0000)]
afs: Fix some dentry handling in dir ops and missing key_puts
Fix some of dentry handling in AFS directory ops:
(1) Do d_drop() on the new_dentry before assigning a new inode to it in
afs_vnode_new_inode(). It's fine to do this before calling afs_iget()
because the operation has taken place on the server.
(2) Replace d_instantiate()/d_rehash() with d_add().
(3) Don't d_drop() the new_dentry in afs_rename() on error.
Also fix afs_link() and afs_rename() to call key_put() on all error paths
where the key is taken.
Signed-off-by: David Howells <dhowells@redhat.com>
David Howells [Sat, 18 Nov 2017 00:13:30 +0000 (00:13 +0000)]
afs: Make afs_write_begin() avoid writing to a page that's being stored
Make afs_write_begin() wait for a page that's marked PG_writeback because:
(1) We need to avoid interference with the data being stored so that the
data on the server ends up in a defined state.
(2) page->private is used to track the window of dirty data within a page,
but it's also used by the storage code to track what's being written,
being cleared by the completion notification. Ownership can't be
relinquished by the storage code until completion because it a store
fails, the data must be remarked dirty.
Tracing shows something like the following (edited):
The clear (completion) corresponding to the store+ (store continuation from
a previous page) happens between the second begin (afs_write_begin) and the
store corresponding to that. This results in the second store not seeing
any data to write back, leading to the following warning:
Thomas Gleixner [Wed, 22 Nov 2017 12:05:48 +0000 (13:05 +0100)]
sched/debug: Fix task state recording/printout
The recent conversion of the task state recording to use task_state_index()
broke the sched_switch tracepoint task state output.
task_state_index() returns surprisingly an index (0-7) which is then
printed with __print_flags() applying bitmasks. Not really working and
resulting in weird states like 'prev_state=t' instead of 'prev_state=I'.
Use TASK_REPORT_MAX instead of TASK_STATE_MAX to report preemption. Build a
bitmask from the return value of task_state_index() and store it in
entry->prev_state, which makes __print_flags() work as expected.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: stable@vger.kernel.org Fixes: efb40f588b43 ("sched/tracing: Fix trace_sched_switch task-state printing") Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1711221304180.1751@nanos Signed-off-by: Ingo Molnar <mingo@kernel.org>
Masami Hiramatsu [Fri, 24 Nov 2017 04:56:30 +0000 (13:56 +0900)]
x86/decoder: Add new TEST instruction pattern
The kbuild test robot reported this build warning:
Warning: arch/x86/tools/test_get_len found difference at <jump_table>:ffffffff8103dd2c
Warning: ffffffff8103dd82: f6 09 d8 testb $0xd8,(%rcx)
Warning: objdump says 3 bytes, but insn_get_length() says 2
Warning: decoded and checked 1569014 instructions with 1 warnings
This sequence seems to be a new instruction not in the opcode map in the Intel SDM.
The instruction sequence is "F6 09 d8", means Group3(F6), MOD(00)REG(001)RM(001), and 0xd8.
Intel SDM vol2 A.4 Table A-6 said the table index in the group is "Encoding of Bits 5,4,3 of
the ModR/M Byte (bits 2,1,0 in parenthesis)"
In that table, opcodes listed by the index REG bits as:
1) Fix PCI IDs of 9000 series iwlwifi devices, from Luca Coelho.
2) bpf offload bug fixes from Jakub Kicinski.
3) Fix bpf verifier to NOP out code which is dead at run time because
due to branch pruning the verifier will not explore such
instructions. From Alexei Starovoitov.
4) Fix crash when deleting secondary chains in packet scheduler
classifier. From Roman Kapl.
5) Fix buffer management bugs in smc, from Ursula Braun.
6) Fix regression in anycast route handling, from David Ahern.
7) Fix link settings regression in r8169, from Tobias Jakobi.
8) Add back enough UFO support so that live migration still works, from
Willem de Bruijn.
9) Linearize enough packet data for the full extent to which the ipvlan
code will inspect the packet headers, from Gao Feng.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (46 commits)
ipvlan: Fix insufficient skb linear check for ipv6 icmp
ipvlan: Fix insufficient skb linear check for arp
geneve: only configure or fill UDP_ZERO_CSUM6_RX/TX info when CONFIG_IPV6
net: dsa: bcm_sf2: Clear IDDQ_GLOBAL_PWR bit for PHY
net: accept UFO datagrams from tuntap and packet
net: realtek: r8169: implement set_link_ksettings()
net: ipv6: Fixup device for anycast routes during copy
net/smc: Fix preinitialization of buf_desc in __smc_buf_create()
net/smc: use sk_rcvbuf as start for rmb creation
ipv6: Do not consider linkdown nexthops during multipath
net: sched: fix crash when deleting secondary chains
net: phy: cortina: add missing MODULE_DESCRIPTION/AUTHOR/LICENSE
bpf: fix branch pruning logic
bpf: change bpf_perf_event_output arg5 type to ARG_CONST_SIZE_OR_ZERO
bpf: change bpf_probe_read_str arg2 type to ARG_CONST_SIZE_OR_ZERO
bpf: remove explicit handling of 0 for arg2 in bpf_probe_read
bpf: introduce ARG_PTR_TO_MEM_OR_NULL
i40evf: Use smp_rmb rather than read_barrier_depends
fm10k: Use smp_rmb rather than read_barrier_depends
igb: Use smp_rmb rather than read_barrier_depends
...
Linus Torvalds [Fri, 24 Nov 2017 07:14:30 +0000 (21:14 -1000)]
Merge tag 'platform-drivers-x86-v4.15-2' of git://git.infradead.org/linux-platform-drivers-x86
Pull x86 platform driver fixes from Darren Hart:
"Fix two issues resulting from the dell-smbios refactoring and
introduction of the dell-smbios-wmi dispatcher.
The first ensures a proper error code is returned when kzalloc fails.
The second avoids an issue in older Dell BIOS implementations which
would fail if the more complex calls were made by limiting those
platforms to the simple calls such as those used by the existing
dell-laptop and dell-wmi drivers, preserving their functionality prior
to the addition of the dell-smbios-wmi dispatcher"
* tag 'platform-drivers-x86-v4.15-2' of git://git.infradead.org/linux-platform-drivers-x86:
platform/x86: dell-laptop: fix error return code in dell_init()
platform/x86: dell-smbios-wmi: Disable userspace interface if missing hotfix
Linus Torvalds [Fri, 24 Nov 2017 07:12:58 +0000 (21:12 -1000)]
Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"Two basic fixes: one for the sparse problem with the blacklist flags
and another for a hang forever in bnx2i"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: Use 'blist_flags_t' for scsi_devinfo flags
scsi: bnx2fc: Fix hung task messages when a cleanup response is not received during abort