Commit Graph

26908 Commits

Author SHA1 Message Date
Tom Zanussi
c282a386a3 tracing: Add 'onmatch' hist trigger action support
Add an 'onmatch(matching.event).<synthetic_event_name>(param list)'
hist trigger action which is invoked with the set of variables or
event fields named in the 'param list'.  The result is the generation
of a synthetic event that consists of the values contained in those
variables and/or fields at the time the invoking event was hit.

As an example the below defines a simple synthetic event using a
variable defined on the sched_wakeup_new event, and shows the event
definition with unresolved fields, since the sched_wakeup_new event
with the testpid variable hasn't been defined yet:

    # echo 'wakeup_new_test pid_t pid; int prio' >> \
      /sys/kernel/debug/tracing/synthetic_events

    # cat /sys/kernel/debug/tracing/synthetic_events
      wakeup_new_test pid_t pid; int prio

The following hist trigger both defines a testpid variable and
specifies an onmatch() trace action that uses that variable along with
a non-variable field to generate a wakeup_new_test synthetic event
whenever a sched_wakeup_new event occurs, which because of the 'if
comm == "cyclictest"' filter only happens when the executable is
cyclictest:

    # echo 'hist:testpid=pid:keys=$testpid:\
      onmatch(sched.sched_wakeup_new).wakeup_new_test($testpid, prio) \
        if comm=="cyclictest"' >> \
      /sys/kernel/debug/tracing/events/sched/sched_wakeup_new/trigger

Creating and displaying a histogram based on those events is now just
a matter of using the fields and new synthetic event in the
tracing/events/synthetic directory, as usual:

    # echo 'hist:keys=pid,prio:sort=pid,prio' >> \
      /sys/kernel/debug/tracing/events/synthetic/wakeup_new_test/trigger

Link: http://lkml.kernel.org/r/8c2a574bcb7530c876629c901ecd23911b14afe8.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Rajvi Jingar <rajvi.jingar@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:59 -05:00
Tom Zanussi
02205a6752 tracing: Add support for 'field variables'
Users should be able to directly specify event fields in hist trigger
'actions' rather than being forced to explicitly create a variable for
that purpose.

Add support allowing fields to be used directly in actions, which
essentially does just that - creates 'invisible' variables for each
bare field specified in an action.  If a bare field refers to a field
on another (matching) event, it even creates a special histogram for
the purpose (since variables can't be defined on an existing histogram
after histogram creation).

Here's a simple example that demonstrates both.  Basically the
onmatch() action creates a list of variables corresponding to the
parameters of the synthetic event to be generated, and then uses those
values to generate the event.  So for the wakeup_latency synthetic
event 'call' below the first param, $wakeup_lat, is a variable defined
explicitly on sched_switch, where 'next_pid' is just a normal field on
sched_switch, and prio is a normal field on sched_waking.

Since the mechanism works on variables, those two normal fields just
have 'invisible' variables created internally for them.  In the case of
'prio', which is on another event, we actually need to create an
additional hist trigger and define the invisible variable on that, since
once a hist trigger is defined, variables can't be added to it later.

  echo 'wakeup_latency u64 lat; pid_t pid; int prio' >>
       /sys/kernel/debug/tracing/synthetic_events

  echo 'hist:keys=pid:ts0=common_timestamp.usecs >>
       /sys/kernel/debug/tracing/events/sched/sched_waking/trigger

echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0:
      onmatch(sched.sched_waking).wakeup_latency($wakeup_lat,next_pid,prio)
            >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger

Link: http://lkml.kernel.org/r/8e8dcdac1ea180ed7a3689e1caeeccede9dc42b3.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:59 -05:00
Tom Zanussi
4b147936fa tracing: Add support for 'synthetic' events
Synthetic events are user-defined events generated from hist trigger
variables saved from one or more other events.

To define a synthetic event, the user writes a simple specification
consisting of the name of the new event along with one or more
variables and their type(s), to the tracing/synthetic_events file.

For instance, the following creates a new event named 'wakeup_latency'
with 3 fields: lat, pid, and prio:

    # echo 'wakeup_latency u64 lat; pid_t pid; int prio' >> \
      /sys/kernel/debug/tracing/synthetic_events

Reading the tracing/synthetic_events file lists all the
currently-defined synthetic events, in this case the event we defined
above:

    # cat /sys/kernel/debug/tracing/synthetic_events
    wakeup_latency u64 lat; pid_t pid; int prio

At this point, the synthetic event is ready to use, and a histogram
can be defined using it:

    # echo 'hist:keys=pid,prio,lat.log2:sort=pid,lat' >> \
    /sys/kernel/debug/tracing/events/synthetic/wakeup_latency/trigger

The new event is created under the tracing/events/synthetic/ directory
and looks and behaves just like any other event:

    # ls /sys/kernel/debug/tracing/events/synthetic/wakeup_latency
      enable  filter  format  hist  id  trigger

Although a histogram can be defined for it, nothing will happen until
an action tracing that event via the trace_synth() function occurs.
The trace_synth() function is very similar to all the other trace_*
invocations spread throughout the kernel, except in this case the
trace_ function and its corresponding tracepoint isn't statically
generated but defined by the user at run-time.

How this can be automatically hooked up via a hist trigger 'action' is
discussed in a subsequent patch.

Link: http://lkml.kernel.org/r/c68df2284b7d172669daf9be29db62ad49bbc559.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
[fix noderef.cocci warnings, sizeof pointer for kcalloc of event->fields]
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:58 -05:00
Tom Zanussi
0212e2aa30 tracing: Add hist trigger action hook
Add a hook for executing extra actions whenever a histogram entry is
added or updated.

The default 'action' when a hist entry is added to a histogram is to
update the set of values associated with it.  Some applications may
want to perform additional actions at that point, such as generate
another event, or compare and save a maximum.

Add a simple framework for doing that; specific actions will be
implemented on top of it in later patches.

Link: http://lkml.kernel.org/r/9482ba6a3eaf5ca6e60954314beacd0e25c05b24.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:58 -05:00
Tom Zanussi
067fe038e7 tracing: Add variable reference handling to hist triggers
Add the necessary infrastructure to allow the variables defined on one
event to be referenced in another.  This allows variables set by a
previous event to be referenced and used in expressions combining the
variable values saved by that previous event and the event fields of
the current event.  For example, here's how a latency can be
calculated and saved into yet another variable named 'wakeup_lat':

    # echo 'hist:keys=pid,prio:ts0=common_timestamp ...
    # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp-$ts0 ...

In the first event, the event's timetamp is saved into the variable
ts0.  In the next line, ts0 is subtracted from the second event's
timestamp to produce the latency.

Further users of variable references will be described in subsequent
patches, such as for instance how the 'wakeup_lat' variable above can
be displayed in a latency histogram.

Link: http://lkml.kernel.org/r/b1d3e6975374e34d501ff417c20189c3f9b2c7b8.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:58 -05:00
Tom Zanussi
19a9facd0f tracing: Add hist_field 'type' field
Future support for synthetic events requires hist_field 'type'
information, so add a field for that.

Also, make other hist_field attribute usage consistent (size,
is_signed, etc).

Link: http://lkml.kernel.org/r/3fd12a2e86316b05151ba0d7c68268e780af2c9d.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:57 -05:00
Tom Zanussi
df35d93bbf tracing: Pass tracing_map_elt to hist_field accessor functions
Some accessor functions, such as for variable references, require
access to a corrsponding tracing_map_elt.

Add a tracing_map_elt param to the function signature and update the
accessor functions accordingly.

Link: http://lkml.kernel.org/r/e0f292b068e9e4948da1d5af21b5ae0efa9b5717.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:57 -05:00
Tom Zanussi
af6a29bcaf tracing: Generalize per-element hist trigger data
Up until now, hist triggers only needed per-element support for saving
'comm' data, which was saved directly as a private data pointer.

In anticipation of the need to save other data besides 'comm', add a
new hist_elt_data struct for the purpose, and switch the current
'comm'-related code over to that.

Link: http://lkml.kernel.org/r/4502c338c965ddf5fc19fb1ec4764391e001ed4b.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:56 -05:00
Tom Zanussi
100719dcef tracing: Add simple expression support to hist triggers
Add support for simple addition, subtraction, and unary expressions
(-(expr) and expr, where expr = b-a, a+b, a+b+c) to hist triggers, in
order to support a minimal set of useful inter-event calculations.

These operations are needed for calculating latencies between events
(timestamp1-timestamp0) and for combined latencies (latencies over 3
or more events).

In the process, factor out some common code from key and value
parsing.

Link: http://lkml.kernel.org/r/9a9308ead4fe32a433d9c7e95921fb798394f6b2.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
[kbuild test robot fix, add static to parse_atom()]
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
[ Replaced '//' comments with normal /* */ comments ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:56 -05:00
Tom Zanussi
2ece94fbd2 tracing: Move get_hist_field_flags()
Move get_hist_field_flags() to make it more easily accessible for new
code (and keep the move separate from new functionality).

Link: http://lkml.kernel.org/r/32470f0a7047ec7a6e84ba5ec89d6142cc6ede7d.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:55 -05:00
Tom Zanussi
1a361dfcf2 tracing: Account for variables in named trigger compatibility
Named triggers must also have the same set of variables in order to be
considered compatible - update the trigger match test to account for
that.

The reason for this requirement is that named triggers with variables
are meant to allow one or more events to set the same variable.

Link: http://lkml.kernel.org/r/a17eae6328a99917f9d5c66129c9fcd355279ee9.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:55 -05:00
Tom Zanussi
30350d65ac tracing: Add variable support to hist triggers
Add support for saving the value of a current event's event field by
assigning it to a variable that can be read by a subsequent event.

The basic syntax for saving a variable is to simply prefix a unique
variable name not corresponding to any keyword along with an '=' sign
to any event field.

Both keys and values can be saved and retrieved in this way:

    # echo 'hist:keys=next_pid:vals=$ts0:ts0=common_timestamp ...
    # echo 'hist:timer_pid=common_pid:key=$timer_pid ...'

If a variable isn't a key variable or prefixed with 'vals=', the
associated event field will be saved in a variable but won't be summed
as a value:

    # echo 'hist:keys=next_pid:ts1=common_timestamp:...

Multiple variables can be assigned at the same time:

    # echo 'hist:keys=pid:vals=$ts0,$b,field2:ts0=common_timestamp,b=field1 ...

Multiple (or single) variables can also be assigned at the same time
using separate assignments:

    # echo 'hist:keys=pid:vals=$ts0:ts0=common_timestamp:b=field1:c=field2 ...

Variables set as above can be used by being referenced from another
event, as described in a subsequent patch.

Link: http://lkml.kernel.org/r/fc93c4944d9719dbcb1d0067be627d44e98e2adc.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Baohong Liu <baohong.liu@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:54 -05:00
Tom Zanussi
860f9f6b02 tracing: Add usecs modifier for hist trigger timestamps
Appending .usecs onto a common_timestamp field will cause the
timestamp value to be in microseconds instead of the default
nanoseconds.  A typical latency histogram using usecs would look like
this:

   # echo 'hist:keys=pid,prio:ts0=common_timestamp.usecs ...
   # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0 ...

This also adds an external trace_clock_in_ns() to trace.c for the
timestamp conversion.

Link: http://lkml.kernel.org/r/4e813705a170b3e13e97dc3135047362fb1a39f3.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:54 -05:00
Tom Zanussi
b559d003a2 tracing: Add hist_data member to hist_field
Allow hist_data access via hist_field.  Some users of hist_fields
require or will require more access to the associated hist_data.

Link: http://lkml.kernel.org/r/d04cd0768f5228ebb4ac0ba4a847bc4d14d4826f.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:53 -05:00
Tom Zanussi
2734b62952 tracing: Add per-element variable support to tracing_map
In order to allow information to be passed between trace events, add
support for per-element variables to tracing_map.  This provides a
means for histograms to associate a value or values with an entry when
it's saved or updated, and retrieved by a subsequent event occurrences.

Variables can be set using tracing_map_set_var() and read using
tracing_map_read_var().  tracing_map_var_set() returns true or false
depending on whether or not the variable has been set or not, which is
important for event-matching applications.

tracing_map_read_var_once() reads the variable and resets it to the
'unset' state, implementing read-once variables, which are also
important for event-matching uses.

Link: http://lkml.kernel.org/r/7fa001108252556f0c6dd9d63145eabfe3370d1a.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:53 -05:00
Tom Zanussi
ad42febe51 tracing: Add hist trigger timestamp support
Add support for a timestamp event field.  This is actually a 'pseudo-'
event field in that it behaves like it's part of the event record, but
is really part of the corresponding ring buffer event.

To make use of the timestamp field, users can specify
"common_timestamp" as a field name for any histogram.  Note that this
doesn't make much sense on its own either as either a key or value,
but needs to be supported even so, since follow-on patches will add
support for making use of this field in time deltas.  The
common_timestamp 'field' is not a bona fide event field - so you won't
find it in the event description - but rather it's a synthetic field
that can be used like a real field.

Note that the use of this field requires the ring buffer be put into
'absolute timestamp' mode, which saves the complete timestamp for each
event rather than an offset.  This mode will be enabled if and only if
a histogram makes use of the "common_timestamp" field.

Link: http://lkml.kernel.org/r/97afbd646ed146e26271f3458b4b33e16d7817c2.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Baohong Liu <baohong.liu@intel.com>
[kasan use-after-free fix]
Signed-off-by: Vedang Patel <vedang.patel@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:52 -05:00
Tom Zanussi
9b1ae035c9 tracing: Break out hist trigger assignment parsing
This will make it easier to add variables, and makes the parsing code
cleaner regardless.

Link: http://lkml.kernel.org/r/e574b3291bbe15e35a4dfc87e5395aa715701c98.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Rajvi Jingar <rajvi.jingar@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:52 -05:00
Tom Zanussi
fbd302cbeb tracing: Add ring buffer event param to hist field functions
Some events such as timestamps require access to a ring_buffer_event
struct; add a param so that hist field functions can access that.

Link: http://lkml.kernel.org/r/2ff4af18e72b6002eb86b26b2a7f39cef7d1dfe4.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:52 -05:00
Tom Zanussi
1ac4f51c0e tracing: Give event triggers access to ring_buffer_event
The ring_buffer event can provide a timestamp that may be useful to
various triggers - pass it into the handlers for that purpose.

Link: http://lkml.kernel.org/r/6de592683b59fa70ffa5d43d0109896623fc1367.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:51 -05:00
Tom Zanussi
2c1ea60b19 tracing: Add timestamp_mode trace file
Add a new option flag indicating whether or not the ring buffer is in
'absolute timestamp' mode.

Currently this is only set/unset by hist triggers that make use of a
common_timestamp.  As such, there's no reason to make this writeable
for users - its purpose is only to allow users to determine
unequivocally whether or not the ring buffer is in that mode (although
absolute timestamps can coexist with the normal delta timestamps, when
the ring buffer is in absolute mode, timestamps written while absolute
mode is in effect take up more space in the buffer, and are not as
efficient).

Link: http://lkml.kernel.org/r/e8aa7b1cde1cf15014e66545d06ac6ef2ebba456.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:51 -05:00
Tom Zanussi
dc4e2801d4 ring-buffer: Redefine the unimplemented RINGBUF_TYPE_TIME_STAMP
RINGBUF_TYPE_TIME_STAMP is defined but not used, and from what I can
gather was reserved for something like an absolute timestamp feature
for the ring buffer, if not a complete replacement of the current
time_delta scheme.

This code redefines RINGBUF_TYPE_TIME_STAMP to implement absolute time
stamps.  Another way to look at it is that it essentially forces
extended time_deltas for all events.

The motivation for doing this is to enable time_deltas that aren't
dependent on previous events in the ring buffer, making it feasible to
use the ring_buffer_event timetamps in a more random-access way, for
purposes other than serial event printing.

To set/reset this mode, use tracing_set_timestamp_abs() from the
previous interface patch.

Link: http://lkml.kernel.org/r/477b362dba1ce7fab9889a1a8e885a62c472f041.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:50 -05:00
Tom Zanussi
00b4145298 ring-buffer: Add interface for setting absolute time stamps
Define a new function, tracing_set_time_stamp_abs(), which can be used
to enable or disable the use of absolute timestamps rather than time
deltas for a trace array.

Only the interface is added here; a subsequent patch will add the
underlying implementation.

Link: http://lkml.kernel.org/r/ce96119de44c7fe0ee44786d15254e9b493040d3.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Baohong Liu <baohong.liu@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:50 -05:00
Vedang Patel
c193707dde tracing: Remove code which merges duplicates
We now have the logic to detect and remove duplicates in the
tracing_map hash table. The code which merges duplicates in the
histogram is redundant now. So, modify this code just to detect
duplicates. The duplication detection code is still kept to ensure
that any rare race condition which might cause duplicates does not go
unnoticed.

Link: http://lkml.kernel.org/r/55215cf59e2674391bdaf772fdafc4c393352b03.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Vedang Patel <vedang.patel@intel.com>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:49 -05:00
Vedang Patel
cbf4100efb tracing: Add support to detect and avoid duplicates
A duplicate in the tracing_map hash table is when 2 different entries
have the same key and, as a result, the key_hash. This is possible due
to a race condition in the algorithm. This race condition is inherent to
the algorithm and not a bug. This was fine because, until now, we were
only interested in the sum of all the values related to a particular
key (the duplicates are dealt with in tracing_map_sort_entries()). But,
with the inclusion of variables[1], we are interested in individual
values. So, it will not be clear what value to choose when
there are duplicates. So, the duplicates need to be removed.

The duplicates can occur in the code in the following scenarios:

- A thread is in the process of adding a new element. It has
successfully executed cmpxchg() and inserted the key. But, it is still
not done acquiring the trace_map_elt struct, populating it and storing
the pointer to the struct in the value field of tracing_map hash table.
If another thread comes in at this time and wants to add an element with
the same key, it will not see the current element and add a new one.

- There are multiple threads trying to execute cmpxchg at the same time,
one of the threads will succeed and the others will fail. The ones which
fail will go ahead increment 'idx' and add a new element there creating
a duplicate.

This patch detects and avoids the first condition by asking the thread
which detects the duplicate to loop one more time. There is also a
possibility of infinite loop if the thread which is trying to insert
goes to sleep indefinitely and the one which is trying to insert a new
element detects a duplicate. Which is why, the thread loops for
map_size iterations before returning NULL.

The second scenario is avoided by preventing the threads which failed
cmpxchg() from incrementing idx. This way, they will loop
around and check if the thread which succeeded in executing cmpxchg()
had the same key.

[1] http://lkml.kernel.org/r/cover.1498510759.git.tom.zanussi@linux.intel.com

Link: http://lkml.kernel.org/r/e178e89ec399240331d383bd5913d649713110f4.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Vedang Patel <vedang.patel@intel.com>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:49 -05:00
Linus Torvalds
4c4ce3022d Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Thomas Gleixner:
 "A small set of fixes from the timer departement:

   - Add a missing timer wheel clock forward when migrating timers off a
     unplugged CPU to prevent operating on a stale clock base and
     missing timer deadlines.

   - Use the proper shift count to extract data from a register value to
     prevent evaluating unrelated bits

   - Make the error return check in the FSL timer driver work correctly.
     Checking an unsigned variable for less than zero does not really
     work well.

   - Clarify the confusing comments in the ARC timer code"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  timers: Forward timer base before migrating timers
  clocksource/drivers/arc_timer: Update some comments
  clocksource/drivers/mips-gic-timer: Use correct shift count to extract data
  clocksource/drivers/fsl_ftm_timer: Fix error return checking
2018-03-04 11:34:49 -08:00
Linus Torvalds
20f14172cb Merge branch 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm fixes from Dan Williams:
 "A 4.16 regression fix, three fixes for -stable, and a cleanup fix:

   - During the merge window support for the new ACPI NVDIMM Platform
     Capabilities structure disabled support for "deep flush", a
     force-unit- access like mechanism for persistent memory. Restore
     that mechanism.

   - VFIO like RDMA is yet one more memory registration / pinning
     interface that is incompatible with Filesystem-DAX. Disable long
     term pins of Filesystem-DAX mappings via VFIO.

   - The Filesystem-DAX detection to prevent long terms pins mistakenly
     also disabled Device-DAX pins which are not subject to the same
     block- map collision concerns.

   - Similar to the setup path, softlockup warnings can trigger in the
     shutdown path for large persistent memory namespaces. Teach
     for_each_device_pfn() to perform cond_resched() in all cases.

   - Boaz noticed that the might_sleep() in dax_direct_access() is stale
     as of the v4.15 kernel.

  These have received a build success notification from the 0day robot,
  and the longterm pin fixes have appeared in -next. However, I recently
  rebased the tree to remove some other fixes that need to be reworked
  after review feedback.

* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  memremap: fix softlockup reports at teardown
  libnvdimm: re-enable deep flush for pmem devices via fsync()
  vfio: disable filesystem-dax page pinning
  dax: fix vma_is_fsdax() helper
  dax: ->direct_access does not sleep anymore
2018-03-03 14:32:00 -08:00
Dan Williams
949b93250a memremap: fix softlockup reports at teardown
The cond_resched() currently in the setup path needs to be duplicated in
the teardown path. Rather than require each instance of
for_each_device_pfn() to open code the same sequence, embed it in the
helper.

Link: https://github.com/intel/ixpdimm_sw/issues/11
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: <stable@vger.kernel.org>
Fixes: 7138970383 ("mm, zone_device: Replace {get, put}_zone_device_page()...")
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-03-02 19:34:50 -08:00
Linus Torvalds
7bec4a9646 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk
Pull printk fix from Petr Mladek:
 "Make sure that we wake up userspace loggers. This fixes a race
  introduced by the console waiter logic during this merge window"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk:
  printk: Wake klogd when passing console_lock owner
2018-03-01 10:06:39 -08:00
Lingutla Chandrasekhar
c52232a49e timers: Forward timer base before migrating timers
On CPU hotunplug the enqueued timers of the unplugged CPU are migrated to a
live CPU. This happens from the control thread which initiated the unplug.

If the CPU on which the control thread runs came out from a longer idle
period then the base clock of that CPU might be stale because the control
thread runs prior to any event which forwards the clock.

In such a case the timers from the unplugged CPU are queued on the live CPU
based on the stale clock which can cause large delays due to increased
granularity of the outer timer wheels which are far away from base:;clock.

But there is a worse problem than that. The following sequence of events
illustrates it:

 - CPU0 timer1 is queued expires = 59969 and base->clk = 59131.

   The timer is queued at wheel level 2, with resulting expiry time = 60032
   (due to level granularity).

 - CPU1 enters idle @60007, with next timer expiry @60020.

 - CPU0 is hotplugged at @60009

 - CPU1 exits idle and runs the control thread which migrates the
   timers from CPU0

   timer1 is now queued in level 0 for immediate handling in the next
   softirq because the requested expiry time 59969 is before CPU1 base->clk
   60007

 - CPU1 runs code which forwards the base clock which succeeds because the
   next expiring timer. which was collected at idle entry time is still set
   to 60020.

   So it forwards beyond 60007 and therefore misses to expire the migrated
   timer1. That timer gets expired when the wheel wraps around again, which
   takes between 63 and 630ms depending on the HZ setting.

Address both problems by invoking forward_timer_base() for the control CPUs
timer base. All other places, which might run into a similar problem
(mod_timer()/add_timer_on()) already invoke forward_timer_base() to avoid
that.

[ tglx: Massaged comment and changelog ]

Fixes: a683f390b9 ("timers: Forward the wheel clock whenever possible")
Co-developed-by: Neeraj Upadhyay <neeraju@codeaurora.org>
Signed-off-by: Neeraj Upadhyay <neeraju@codeaurora.org>
Signed-off-by: Lingutla Chandrasekhar <clingutla@codeaurora.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: linux-arm-msm@vger.kernel.org
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180118115022.6368-1-clingutla@codeaurora.org
2018-02-28 23:34:33 +01:00
Petr Mladek
c14376de3a printk: Wake klogd when passing console_lock owner
wake_klogd is a local variable in console_unlock(). The information
is lost when the console_lock owner using the busy wait added by
the commit dbdda842fe ("printk: Add console owner and waiter
logic to load balance console writes"). The following race is
possible:

CPU0				CPU1
console_unlock()

  for (;;)
     /* calling console for last message */

				printk()
				  log_store()
				    log_next_seq++;

     /* see new message */
     if (seen_seq != log_next_seq) {
	wake_klogd = true;
	seen_seq = log_next_seq;
     }

     console_lock_spinning_enable();

				  if (console_trylock_spinning())
				     /* spinning */

     if (console_lock_spinning_disable_and_check()) {
	printk_safe_exit_irqrestore(flags);
	return;

				  console_unlock()
				    if (seen_seq != log_next_seq) {
				    /* already seen */
				    /* nothing to do */

Result: Nobody would wakeup klogd.

One solution would be to make a global variable from wake_klogd.
But then we would need to manipulate it under a lock or so.

This patch wakes klogd also when console_lock is passed to the
spinning waiter. It looks like the right way to go. Also userspace
should have a chance to see and store any "flood" of messages.

Note that the very late klogd wake up was a historic solution.
It made sense on single CPU systems or when sys_syslog() operations
were synchronized using the big kernel lock like in v2.1.113.
But it is questionable these days.

Fixes: dbdda842fe ("printk: Add console owner and waiter logic to load balance console writes")
Link: http://lkml.kernel.org/r/20180226155734.dzwg3aovqnwtvkoy@pathway.suse.cz
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-kernel@vger.kernel.org
Cc: Tejun Heo <tj@kernel.org>
Suggested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-02-27 10:25:50 +01:00
Linus Torvalds
85a2d939c0 Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
 "Yet another pile of melted spectrum related changes:

   - sanitize the array_index_nospec protection mechanism: Remove the
     overengineered array_index_nospec_mask_check() magic and allow
     const-qualified types as index to avoid temporary storage in a
     non-const local variable.

   - make the microcode loader more robust by properly propagating error
     codes. Provide information about new feature bits after micro code
     was updated so administrators can act upon.

   - optimizations of the entry ASM code which reduce code footprint and
     make the code simpler and faster.

   - fix the {pmd,pud}_{set,clear}_flags() implementations to work
     properly on paravirt kernels by removing the address translation
     operations.

   - revert the harmful vmexit_fill_RSB() optimization

   - use IBRS around firmware calls

   - teach objtool about retpolines and add annotations for indirect
     jumps and calls.

   - explicitly disable jumplabel patching in __init code and handle
     patching failures properly instead of silently ignoring them.

   - remove indirect paravirt calls for writing the speculation control
     MSR as these calls are obviously proving the same attack vector
     which is tried to be mitigated.

   - a few small fixes which address build issues with recent compiler
     and assembler versions"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits)
  KVM/VMX: Optimize vmx_vcpu_run() and svm_vcpu_run() by marking the RDMSR path as unlikely()
  KVM/x86: Remove indirect MSR op calls from SPEC_CTRL
  objtool, retpolines: Integrate objtool with retpoline support more closely
  x86/entry/64: Simplify ENCODE_FRAME_POINTER
  extable: Make init_kernel_text() global
  jump_label: Warn on failed jump_label patching attempt
  jump_label: Explicitly disable jump labels in __init code
  x86/entry/64: Open-code switch_to_thread_stack()
  x86/entry/64: Move ASM_CLAC to interrupt_entry()
  x86/entry/64: Remove 'interrupt' macro
  x86/entry/64: Move the switch_to_thread_stack() call to interrupt_entry()
  x86/entry/64: Move ENTER_IRQ_STACK from interrupt macro to interrupt_entry
  x86/entry/64: Move PUSH_AND_CLEAR_REGS from interrupt macro to helper function
  x86/speculation: Move firmware_restrict_branch_speculation_*() from C to CPP
  objtool: Add module specific retpoline rules
  objtool: Add retpoline validation
  objtool: Use existing global variables for options
  x86/mm/sme, objtool: Annotate indirect call in sme_encrypt_execute()
  x86/boot, objtool: Annotate indirect jump in secondary_startup_64()
  x86/paravirt, objtool: Annotate indirect calls
  ...
2018-02-26 09:34:21 -08:00
Linus Torvalds
c23a757591 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
 "A small set of fixes:

   - UAPI data type correction for hyperv

   - correct the cpu cores field in /proc/cpuinfo on CPU hotplug

   - return proper error code in the resctrl file system failure path to
     avoid silent subsequent failures

   - correct a subtle accounting issue in the new vector allocation code
     which went unnoticed for a while and caused suspend/resume
     failures"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/topology: Update the 'cpu cores' field in /proc/cpuinfo correctly across CPU hotplug operations
  x86/topology: Fix function name in documentation
  x86/intel_rdt: Fix incorrect returned value when creating rdgroup sub-directory in resctrl file system
  x86/apic/vector: Handle vector release on CPU unplug correctly
  genirq/matrix: Handle CPU offlining proper
  x86/headers/UAPI: Use __u64 instead of u64 in <uapi/asm/hyperv.h>
2018-02-25 16:58:55 -08:00
Linus Torvalds
9cb9c07d6b Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Fix TTL offset calculation in mac80211 mesh code, from Peter Oh.

 2) Fix races with procfs in ipt_CLUSTERIP, from Cong Wang.

 3) Memory leak fix in lpm_trie BPF map code, from Yonghong Song.

 4) Need to use GFP_ATOMIC in BPF cpumap allocations, from Jason Wang.

 5) Fix potential deadlocks in netfilter getsockopt() code paths, from
    Paolo Abeni.

 6) Netfilter stackpointer size checks really are needed to validate
    user input, from Florian Westphal.

 7) Missing timer init in x_tables, from Paolo Abeni.

 8) Don't use WQ_MEM_RECLAIM in mac80211 hwsim, from Johannes Berg.

 9) When an ibmvnic device is brought down then back up again, it can be
    sent queue entries from a previous session, handle this properly
    instead of crashing. From Thomas Falcon.

10) Fix TCP checksum on LRO buffers in mlx5e, from Gal Pressman.

11) When we are dumping filters in cls_api, the output SKB is empty, and
    the filter we are dumping is too large for the space in the SKB, we
    should return -EMSGSIZE like other netlink dump operations do.
    Otherwise userland has no signal that is needs to increase the size
    of its read buffer. From Roman Kapl.

12) Several XDP fixes for virtio_net, from Jesper Dangaard Brouer.

13) Module refcount leak in netlink when a dump start fails, from Jason
    Donenfeld.

14) Handle sub-optimal GSO sizes better in TCP BBR congestion control,
    from Eric Dumazet.

15) Releasing bpf per-cpu arraymaps can take a long time, add a
    condtional scheduling point. From Eric Dumazet.

16) Implement retpolines for tail calls in x64 and arm64 bpf JITs. From
    Daniel Borkmann.

17) Fix page leak in gianfar driver, from Andy Spencer.

18) Missed clearing of estimator scratch buffer, from Eric Dumazet.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (76 commits)
  net_sched: gen_estimator: fix broken estimators based on percpu stats
  gianfar: simplify FCS handling and fix memory leak
  ipv6 sit: work around bogus gcc-8 -Wrestrict warning
  macvlan: fix use-after-free in macvlan_common_newlink()
  bpf, arm64: fix out of bounds access in tail call
  bpf, x64: implement retpoline for tail call
  rxrpc: Fix send in rxrpc_send_data_packet()
  net: aquantia: Fix error handling in aq_pci_probe()
  bpf: fix rcu lockdep warning for lpm_trie map_free callback
  bpf: add schedule points in percpu arrays management
  regulatory: add NUL to request alpha2
  ibmvnic: Fix early release of login buffer
  net/smc9194: Remove bogus CONFIG_MAC reference
  net: ipv4: Set addr_type in hash_keys for forwarded case
  tcp_bbr: better deal with suboptimal GSO
  smsc75xx: fix smsc75xx_set_features()
  netlink: put module reference if dump start fails
  selftests/bpf/test_maps: exit child process without error in ENOMEM case
  selftests/bpf: update gitignore with test_libbpf_open
  selftests/bpf: tcpbpf_kern: use in6_* macros from glibc
  ..
2018-02-23 15:14:17 -08:00
Linus Torvalds
2eb02aa94f Merge branch 'fixes-v4.16-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem fixes from James Morris:

 - keys fixes via David Howells:
      "A collection of fixes for Linux keyrings, mostly thanks to Eric
       Biggers:

        - Fix some PKCS#7 verification issues.

        - Fix handling of unsupported crypto in X.509.

        - Fix too-large allocation in big_key"

 - Seccomp updates via Kees Cook:
      "These are fixes for the get_metadata interface that landed during
       -rc1. While the new selftest is strictly not a bug fix, I think
       it's in the same spirit of avoiding bugs"

 - an IMA build fix from Randy Dunlap

* 'fixes-v4.16-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  integrity/security: fix digsig.c build error with header file
  KEYS: Use individual pages in big_key for crypto buffers
  X.509: fix NULL dereference when restricting key with unsupported_sig
  X.509: fix BUG_ON() when hash algorithm is unsupported
  PKCS#7: fix direct verification of SignerInfo signature
  PKCS#7: fix certificate blacklisting
  PKCS#7: fix certificate chain verification
  seccomp: add a selftest for get_metadata
  ptrace, seccomp: tweak get_metadata behavior slightly
  seccomp, ptrace: switch get_metadata types to arch independent
2018-02-23 15:04:24 -08:00
Linus Torvalds
8961ca441b exynos, meson, ipuv3, secondary gpu, cirrus, edid quirk fixes
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Merge tag 'drm-fixes-for-v4.16-rc3' of git://people.freedesktop.org/~airlied/linux

Pull drm fixes from Dave Airlie:
 "A bunch of fixes for rc3:

  Exynos:
   - fixes for using monotonic timestamps
   - register definitions
   - removal of unused file

  ipu-v3L
   - minor changes
   - make some register arrays const+static
   - fix some leaks

  meson:
   - fix for vsync

  atomic:
   - fix for memory leak

  EDID parser:
   - add quirks for some more non-desktop devices
   - 6-bit panel fix.

  drm_mm:
   - fix a bug in the core drm mm hole handling

  cirrus:
   - fix lut loading regression

  Lastly there is a deadlock fix around runtime suspend for secondary
  GPUs.

  There was a deadlock between one thread trying to wait for a workqueue
  job to finish in the runtime suspend path, and the workqueue job it
  was waiting for in turn waiting for a runtime_get_sync to return.

  The fixes avoids it by not doing the runtime sync in the workqueue as
  then we always wait for all those tasks to complete before we runtime
  suspend"

* tag 'drm-fixes-for-v4.16-rc3' of git://people.freedesktop.org/~airlied/linux: (25 commits)
  drm/tve200: fix kernel-doc documentation comment include
  drm/edid: quirk Sony PlayStation VR headset as non-desktop
  drm/edid: quirk Windows Mixed Reality headsets as non-desktop
  drm/edid: quirk Oculus Rift headsets as non-desktop
  drm/meson: fix vsync buffer update
  drm: Handle unexpected holes in color-eviction
  drm: exynos: Use proper macro definition for HDMI_I2S_PIN_SEL_1
  drm/exynos: remove exynos_drm_rotator.h
  drm/exynos: g2d: Delete an error message for a failed memory allocation in two functions
  drm/exynos: fix comparison to bitshift when dealing with a mask
  drm/exynos: g2d: use monotonic timestamps
  drm/edid: Add 6 bpc quirk for CPT panel in Asus UX303LA
  gpu: ipu-csi: add 10/12-bit grayscale support to mbus_code_to_bus_cfg
  gpu: ipu-cpmem: add 16-bit grayscale support to ipu_cpmem_set_image
  gpu: ipu-v3: prg: fix device node leak in ipu_prg_lookup_by_phandle
  gpu: ipu-v3: pre: fix device node leak in ipu_pre_lookup_by_phandle
  drm/amdgpu: Fix deadlock on runtime suspend
  drm/radeon: Fix deadlock on runtime suspend
  drm/nouveau: Fix deadlock on runtime suspend
  drm: Allow determining if current task is output poll worker
  ...
2018-02-23 10:31:31 -08:00
Thomas Gleixner
651ca2c004 genirq/matrix: Handle CPU offlining proper
At CPU hotunplug the corresponding per cpu matrix allocator is shut down and
the allocated interrupt bits are discarded under the assumption that all
allocated bits have been either migrated away or shut down through the
managed interrupts mechanism.

This is not true because interrupts which are not started up might have a
vector allocated on the outgoing CPU. When the interrupt is started up
later or completely shutdown and freed then the allocated vector is handed
back, triggering warnings or causing accounting issues which result in
suspend failures and other issues.

Change the CPU hotplug mechanism of the matrix allocator so that the
remaining allocations at unplug time are preserved and global accounting at
hotplug is correctly readjusted to take the dormant vectors into account.

Fixes: 2f75d9e1c9 ("genirq: Implement bitmap matrix allocator")
Reported-by: Yuriy Vostrikov <delamonpansie@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Yuriy Vostrikov <delamonpansie@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180222112316.849980972@linutronix.de
2018-02-22 22:05:43 +01:00
Yonghong Song
6c5f61023c bpf: fix rcu lockdep warning for lpm_trie map_free callback
Commit 9a3efb6b66 ("bpf: fix memory leak in lpm_trie map_free callback function")
fixed a memory leak and removed unnecessary locks in map_free callback function.
Unfortrunately, it introduced a lockdep warning. When lockdep checking is turned on,
running tools/testing/selftests/bpf/test_lpm_map will have:

  [   98.294321] =============================
  [   98.294807] WARNING: suspicious RCU usage
  [   98.295359] 4.16.0-rc2+ #193 Not tainted
  [   98.295907] -----------------------------
  [   98.296486] /home/yhs/work/bpf/kernel/bpf/lpm_trie.c:572 suspicious rcu_dereference_check() usage!
  [   98.297657]
  [   98.297657] other info that might help us debug this:
  [   98.297657]
  [   98.298663]
  [   98.298663] rcu_scheduler_active = 2, debug_locks = 1
  [   98.299536] 2 locks held by kworker/2:1/54:
  [   98.300152]  #0:  ((wq_completion)"events"){+.+.}, at: [<00000000196bc1f0>] process_one_work+0x157/0x5c0
  [   98.301381]  #1:  ((work_completion)(&map->work)){+.+.}, at: [<00000000196bc1f0>] process_one_work+0x157/0x5c0

Since actual trie tree removal happens only after no other
accesses to the tree are possible, replacing
  rcu_dereference_protected(*slot, lockdep_is_held(&trie->lock))
with
  rcu_dereference_protected(*slot, 1)
fixed the issue.

Fixes: 9a3efb6b66 ("bpf: fix memory leak in lpm_trie map_free callback function")
Reported-by: Eric Dumazet <edumazet@google.com>
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-02-22 21:29:12 +01:00
Eric Dumazet
32fff239de bpf: add schedule points in percpu arrays management
syszbot managed to trigger RCU detected stalls in
bpf_array_free_percpu()

It takes time to allocate a huge percpu map, but even more time to free
it.

Since we run in process context, use cond_resched() to yield cpu if
needed.

Fixes: a10423b87a ("bpf: introduce BPF_MAP_TYPE_PERCPU_ARRAY map")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-02-22 21:27:06 +01:00
James Morris
645ae5c51e - Fix seccomp GET_METADATA to deal with field sizes correctly (Tycho Andersen)
- Add selftest to make sure GET_METADATA doesn't regress (Tycho Andersen)
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Merge tag 'seccomp-v4.16-rc3' of https://git.kernel.org/pub/scm/linux/kernel/git/kees/linux into fixes-v4.16-rc3

- Fix seccomp GET_METADATA to deal with field sizes correctly (Tycho Andersen)
- Add selftest to make sure GET_METADATA doesn't regress (Tycho Andersen)
2018-02-22 10:50:24 -08:00
Linus Torvalds
238ca35707 Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
 "16 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm: don't defer struct page initialization for Xen pv guests
  lib/Kconfig.debug: enable RUNTIME_TESTING_MENU
  vmalloc: fix __GFP_HIGHMEM usage for vmalloc_32 on 32b systems
  selftests/memfd: add run_fuse_test.sh to TEST_FILES
  bug.h: work around GCC PR82365 in BUG()
  mm/swap.c: make functions and their kernel-doc agree (again)
  mm/zpool.c: zpool_evictable: fix mismatch in parameter name and kernel-doc
  ida: do zeroing in ida_pre_get()
  mm, swap, frontswap: fix THP swap if frontswap enabled
  certs/blacklist_nohashes.c: fix const confusion in certs blacklist
  kernel/relay.c: limit kmalloc size to KMALLOC_MAX_SIZE
  mm, mlock, vmscan: no more skipping pagevecs
  mm: memcontrol: fix NR_WRITEBACK leak in memcg and system stats
  Kbuild: always define endianess in kconfig.h
  include/linux/sched/mm.h: re-inline mmdrop()
  tools: fix cross-compile var clobbering
2018-02-22 10:45:46 -08:00
Luck, Tony
bef3efbeb8 efivarfs: Limit the rate for non-root to read files
Each read from a file in efivarfs results in two calls to EFI
(one to get the file size, another to get the actual data).

On X86 these EFI calls result in broadcast system management
interrupts (SMI) which affect performance of the whole system.
A malicious user can loop performing reads from efivarfs bringing
the system to its knees.

Linus suggested per-user rate limit to solve this.

So we add a ratelimit structure to "user_struct" and initialize
it for the root user for no limit. When allocating user_struct for
other users we set the limit to 100 per second. This could be used
for other places that want to limit the rate of some detrimental
user action.

In efivarfs if the limit is exceeded when reading, we take an
interruptible nap for 50ms and check the rate limit again.

Signed-off-by: Tony Luck <tony.luck@intel.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-22 10:21:02 -08:00
Tycho Andersen
63bb0045b9 ptrace, seccomp: tweak get_metadata behavior slightly
Previously if users passed a small size for the input structure size, they
would get get odd behavior. It doesn't make sense to pass a structure
smaller than at least filter_off size, so let's just give -EINVAL in this
case.

This changes userspace visible behavior, but was only introduced in commit
26500475ac ("ptrace, seccomp: add support for retrieving seccomp
metadata") in 4.16-rc2, so should be safe to change if merged before then.

Reported-by: Eugene Syromiatnikov <esyr@redhat.com>
Signed-off-by: Tycho Andersen <tycho@tycho.ws>
CC: Kees Cook <keescook@chromium.org>
CC: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
2018-02-21 16:56:03 -08:00
David Rientjes
88913bd8ea kernel/relay.c: limit kmalloc size to KMALLOC_MAX_SIZE
chan->n_subbufs is set by the user and relay_create_buf() does a kmalloc()
of chan->n_subbufs * sizeof(size_t *).

kmalloc_slab() will generate a warning when this fails if
chan->subbufs * sizeof(size_t *) > KMALLOC_MAX_SIZE.

Limit chan->n_subbufs to the maximum allowed kmalloc() size.

Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1802061216100.122576@chino.kir.corp.google.com
Fixes: f6302f1bcd ("relay: prevent integer overflow in relay_open()")
Signed-off-by: David Rientjes <rientjes@google.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-21 15:35:43 -08:00
Andrew Morton
d34bc48f82 include/linux/sched/mm.h: re-inline mmdrop()
As Peter points out, Doing a CALL+RET for just the decrement is a bit silly.

Fixes: d70f2a14b7 ("include/linux/sched/mm.h: uninline mmdrop_async(), etc")
Acked-by: Peter Zijlstra (Intel) <peterz@infraded.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-21 15:35:42 -08:00
Dave Airlie
dfe8db2237 Fixes for 4.16. I contains fixes for deadlock on runtime suspend on few
drivers, a memory leak on non-blocking commits, a crash on color-eviction.
 The is also meson and edid fixes, plus a fix for a doc warning.
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Merge tag 'drm-misc-fixes-2018-02-21' of git://anongit.freedesktop.org/drm/drm-misc into drm-fixes

Fixes for 4.16. I contains fixes for deadlock on runtime suspend on few
drivers, a memory leak on non-blocking commits, a crash on color-eviction.
The is also meson and edid fixes, plus a fix for a doc warning.

* tag 'drm-misc-fixes-2018-02-21' of git://anongit.freedesktop.org/drm/drm-misc:
  drm/tve200: fix kernel-doc documentation comment include
  drm/meson: fix vsync buffer update
  drm: Handle unexpected holes in color-eviction
  drm/edid: Add 6 bpc quirk for CPT panel in Asus UX303LA
  drm/amdgpu: Fix deadlock on runtime suspend
  drm/radeon: Fix deadlock on runtime suspend
  drm/nouveau: Fix deadlock on runtime suspend
  drm: Allow determining if current task is output poll worker
  workqueue: Allow retrieval of current task's work struct
  drm/atomic: Fix memleak on ERESTARTSYS during non-blocking commits
2018-02-22 08:39:26 +10:00
David S. Miller
bf006d18b7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2018-02-20

The following pull-request contains BPF updates for your *net* tree.

The main changes are:

1) Fix a memory leak in LPM trie's map_free() callback function, where
   the trie structure itself was not freed since initial implementation.
   Also a synchronize_rcu() was needed in order to wait for outstanding
   programs accessing the trie to complete, from Yonghong.

2) Fix sock_map_alloc()'s error path in order to correctly propagate
   the -EINVAL error in case of too large allocation requests. This
   was just recently introduced when fixing close hooks via ULP layer,
   fix from Eric.

3) Do not use GFP_ATOMIC in __cpu_map_entry_alloc(). Reason is that this
   will not work with the recent __ptr_ring_init_queue_alloc() conversion
   to kvmalloc_array(), where in case of fallback to vmalloc() that GFP
   flag is invalid, from Jason.

4) Fix two recent syzkaller warnings: i) fix bpf_prog_array_copy_to_user()
   when a prog query with a big number of ids was performed where we'd
   otherwise trigger a warning from allocator side, ii) fix a missing
   mlock precharge on arraymaps, from Daniel.

5) Two fixes for bpftool in order to avoid breaking JSON output when used
   in batch mode, from Quentin.

6) Move a pr_debug() in libbpf in order to avoid having an otherwise
   uninitialized variable in bpf_program__reloc_text(), from Jeremy.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-21 15:37:37 -05:00
Josh Poimboeuf
9fbcc57aa1 extable: Make init_kernel_text() global
Convert init_kernel_text() to a global function and use it in a few
places instead of manually comparing _sinittext and _einittext.

Note that kallsyms.h has a very similar function called
is_kernel_inittext(), but its end check is inclusive.  I'm not sure
whether that's intentional behavior, so I didn't touch it.

Suggested-by: Jason Baron <jbaron@akamai.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/4335d02be8d45ca7d265d2f174251d0b7ee6c5fd.1519051220.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-21 16:54:06 +01:00
Josh Poimboeuf
dc1dd184c2 jump_label: Warn on failed jump_label patching attempt
Currently when the jump label code encounters an address which isn't
recognized by kernel_text_address(), it just silently fails.

This can be dangerous because jump labels are used in a variety of
places, and are generally expected to work.  Convert the silent failure
to a warning.

This won't warn about attempted writes to tracepoints in __init code
after initmem has been freed, as those are already guarded by the
entry->code check.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/de3a271c93807adb7ed48f4e946b4f9156617680.1519051220.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-21 16:54:06 +01:00
Josh Poimboeuf
3335224470 jump_label: Explicitly disable jump labels in __init code
After initmem has been freed, any jump labels in __init code are
prevented from being written to by the kernel_text_address() check in
__jump_label_update().  However, this check is quite broad.  If
kernel_text_address() were to return false for any other reason, the
jump label write would fail silently with no warning.

For jump labels in module init code, entry->code is set to zero to
indicate that the entry is disabled.  Do the same thing for core kernel
init code.  This makes the behavior more consistent, and will also make
it more straightforward to detect non-init jump label write failures in
the next patch.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/c52825c73f3a174e8398b6898284ec20d4deb126.1519051220.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-21 16:54:05 +01:00
Linus Torvalds
9ca2c16f3b Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Thomas Gleixner:
 "Perf tool updates and kprobe fixes:

   - perf_mmap overwrite mode fixes/overhaul, prep work to get 'perf
     top' using it, making it bearable to use it in large core count
     systems such as Knights Landing/Mill Intel systems (Kan Liang)

   - s/390 now uses syscall.tbl, just like x86-64 to generate the
     syscall table id -> string tables used by 'perf trace' (Hendrik
     Brueckner)

   - Use strtoull() instead of home grown function (Andy Shevchenko)

   - Synchronize kernel ABI headers, v4.16-rc1 (Ingo Molnar)

   - Document missing 'perf data --force' option (Sangwon Hong)

   - Add perf vendor JSON metrics for ARM Cortex-A53 Processor (William
     Cohen)

   - Improve error handling and error propagation of ftrace based
     kprobes so failures when installing kprobes are not silently
     ignored and create disfunctional tracepoints"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits)
  kprobes: Propagate error from disarm_kprobe_ftrace()
  kprobes: Propagate error from arm_kprobe_ftrace()
  Revert "tools include s390: Grab a copy of arch/s390/include/uapi/asm/unistd.h"
  perf s390: Rework system call table creation by using syscall.tbl
  perf s390: Grab a copy of arch/s390/kernel/syscall/syscall.tbl
  tools/headers: Synchronize kernel ABI headers, v4.16-rc1
  perf test: Fix test trace+probe_libc_inet_pton.sh for s390x
  perf data: Document missing --force option
  perf tools: Substitute yet another strtoull()
  perf top: Check the latency of perf_top__mmap_read()
  perf top: Switch default mode to overwrite mode
  perf top: Remove lost events checking
  perf hists browser: Add parameter to disable lost event warning
  perf top: Add overwrite fall back
  perf evsel: Expose the perf_missing_features struct
  perf top: Check per-event overwrite term
  perf mmap: Discard legacy interface for mmap read
  perf test: Update mmap read functions for backward-ring-buffer test
  perf mmap: Introduce perf_mmap__read_event()
  perf mmap: Introduce perf_mmap__read_done()
  ...
2018-02-18 12:38:40 -08:00