This patch does not impact existing functionalities.
It contains the changes in perf event area needed for
subsequent bpf_perf_event_read_value and
bpf_perf_prog_read_value helpers.
Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
If the algorithm we're parallelizing is asynchronous we might change
CPUs between padata_do_parallel() and padata_do_serial(). However, we
don't expect this to happen as we need to enqueue the padata object into
the per-cpu reorder queue we took it from, i.e. the same-cpu's parallel
queue.
Ensure we're not switching CPUs for a given padata object by tracking
the CPU within the padata object. If the serial callback gets called on
the wrong CPU, defer invoking padata_reorder() via a kernel worker on
the CPU we're expected to run on.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The reorder timer function runs on the CPU where the timer interrupt was
handled which is not necessarily one of the CPUs of the 'pcpu' CPU mask
set.
Ensure the padata_reorder() callback runs on the correct CPU, which is
one in the 'pcpu' CPU mask set and, preferrably, the next expected one.
Do so by comparing the current CPU with the expected target CPU. If they
match, call padata_reorder() right away. If they differ, schedule a work
item on the target CPU that does the padata_reorder() call for us.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The parallel queue per-cpu data structure gets initialized only for CPUs
in the 'pcpu' CPU mask set. This is not sufficient as the reorder timer
may run on a different CPU and might wrongly decide it's the target CPU
for the next reorder item as per-cpu memory gets memset(0) and we might
be waiting for the first CPU in cpumask.pcpu, i.e. cpu_index 0.
Make the '__this_cpu_read(pd->pqueue->cpu_index) == next_queue->cpu_index'
compare in padata_get_next() fail in this case by initializing the
cpu_index member of all per-cpu parallel queues. Use -1 for unused ones.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Pull watchddog clean-up and fixes from Thomas Gleixner:
"The watchdog (hard/softlockup detector) code is pretty much broken in
its current state. The patch series addresses this by removing all
duct tape and refactoring it into a workable state.
The reasons why I ask for inclusion that late in the cycle are:
1) The code causes lockdep splats vs. hotplug locking which get
reported over and over. Unfortunately there is no easy fix.
2) The risk of breakage is minimal because it's already broken
3) As 4.14 is a long term stable kernel, I prefer to have working
watchdog code in that and the lockdep issues resolved. I wouldn't
ask you to pull if 4.14 wouldn't be a LTS kernel or if the
solution would be easy to backport.
4) The series was around before the merge window opened, but then got
delayed due to the UP failure caused by the for_each_cpu()
surprise which we discussed recently.
Changes vs. V1:
- Addressed your review points
- Addressed the warning in the powerpc code which was discovered late
- Changed two function names which made sense up to a certain point
in the series. Now they match what they do in the end.
- Fixed a 'unused variable' warning, which got not detected by the
intel robot. I triggered it when trying all possible related config
combinations manually. Randconfig testing seems not random enough.
The changes have been tested by and reviewed by Don Zickus and tested
and acked by Micheal Ellerman for powerpc"
* 'core-watchdog-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits)
watchdog/core: Put softlockup_threads_initialized under ifdef guard
watchdog/core: Rename some softlockup_* functions
powerpc/watchdog: Make use of watchdog_nmi_probe()
watchdog/core, powerpc: Lock cpus across reconfiguration
watchdog/core, powerpc: Replace watchdog_nmi_reconfigure()
watchdog/hardlockup/perf: Fix spelling mistake: "permanetely" -> "permanently"
watchdog/hardlockup/perf: Cure UP damage
watchdog/hardlockup: Clean up hotplug locking mess
watchdog/hardlockup/perf: Simplify deferred event destroy
watchdog/hardlockup/perf: Use new perf CPU enable mechanism
watchdog/hardlockup/perf: Implement CPU enable replacement
watchdog/hardlockup/perf: Implement init time detection of perf
watchdog/hardlockup/perf: Implement init time perf validation
watchdog/core: Get rid of the racy update loop
watchdog/core, powerpc: Make watchdog_nmi_reconfigure() two stage
watchdog/sysctl: Clean up sysctl variable name space
watchdog/sysctl: Get rid of the #ifdeffery
watchdog/core: Clean up header mess
watchdog/core: Further simplify sysctl handling
watchdog/core: Get rid of the thread teardown/setup dance
...
If a module is loaded while tracing is enabled, then there's a possibility
that the module init functions were traced. These functions have their name
and address stored by ftrace such that it can translate the function address
that is written into the buffer into a human readable function name.
As userspace tools may be doing the same, they need a way to map function
names to their address as well. This is done through reading /proc/kallsyms.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Pull power management fix from Rafael Wysocki:
"This fixes a code ordering issue in the main suspend-to-idle loop that
causes some "low power S0 idle" conditions to be incorrectly reported
as unmet with suspend/resume debug messages enabled"
* tag 'pm-4.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM / s2idle: Invoke the ->wake() platform callback earlier
The ftrace_mod_map is a descriptor to save module init function names in
case they were traced, and the trace output needs to reference the function
name from the function address. But after the function is unloaded, it
the maps should be freed, as the rest of the function names are as well.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Allow for module init sections to be traced as well as core kernel init
sections. Now that filtering modules functions can be stored, for when they
are loaded, it makes sense to be able to trace them.
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Pull networking fixes from David Miller:
1) Check iwlwifi 9000 reorder buffer out-of-space condition properly,
from Sara Sharon.
2) Fix RCU splat in qualcomm rmnet driver, from Subash Abhinov
Kasiviswanathan.
3) Fix session and tunnel release races in l2tp, from Guillaume Nault
and Sabrina Dubroca.
4) Fix endian bug in sctp_diag_dump(), from Dan Carpenter.
5) Several mlx5 driver fixes from the Mellanox folks (max flow counters
cap check, invalid memory access in IPoIB support, etc.)
6) tun_get_user() should bail if skb->len is zero, from Alexander
Potapenko.
7) Fix RCU lookups in inetpeer, from Eric Dumazet.
8) Fix locking in packet_do_bund().
9) Handle cb->start() error properly in netlink dump code, from Jason
A. Donenfeld.
10) Handle multicast properly in UDP socket early demux code. From Paolo
Abeni.
11) Several erspan bug fixes in ip_gre, from Xin Long.
12) Fix use-after-free in socket filter code, in order to handle the
fact that listener lock is no longer taken during the three-way TCP
handshake. From Eric Dumazet.
13) Fix infoleak in RTM_GETSTATS, from Nikolay Aleksandrov.
14) Fix tail call generation in x86-64 BPF JIT, from Alexei Starovoitov.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (77 commits)
net: 8021q: skip packets if the vlan is down
bpf: fix bpf_tail_call() x64 JIT
net: stmmac: dwmac-rk: Add RK3128 GMAC support
rndis_host: support Novatel Verizon USB730L
net: rtnetlink: fix info leak in RTM_GETSTATS call
socket, bpf: fix possible use after free
mlxsw: spectrum_router: Track RIF of IPIP next hops
mlxsw: spectrum_router: Move VRF refcounting
net: hns3: Fix an error handling path in 'hclge_rss_init_hw()'
net: mvpp2: Fix clock resource by adding an optional bus clock
r8152: add Linksys USB3GIGV1 id
l2tp: fix l2tp_eth module loading
ip_gre: erspan device should keep dst
ip_gre: set tunnel hlen properly in erspan_tunnel_init
ip_gre: check packet length and mtu correctly in erspan_xmit
ip_gre: get key from session_id correctly in erspan_rcv
tipc: use only positive error codes in messages
ppp: fix __percpu annotation
udp: perform source validation for mcast early demux
IPv4: early demux can return an error code
...
with addition of tnum logic the verifier got smart enough and
we can enforce return codes at program load time.
For now do so for cgroup-bpf program types.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
introduce BPF_PROG_QUERY command to retrieve a set of either
attached programs to given cgroup or a set of effective programs
that will execute for events within a cgroup
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
for cgroup bits
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
introduce BPF_F_ALLOW_MULTI flag that can be used to attach multiple
bpf programs to a cgroup.
The difference between three possible flags for BPF_PROG_ATTACH command:
- NONE(default): No further bpf programs allowed in the subtree.
- BPF_F_ALLOW_OVERRIDE: If a sub-cgroup installs some bpf program,
the program in this cgroup yields to sub-cgroup program.
- BPF_F_ALLOW_MULTI: If a sub-cgroup installs some bpf program,
that cgroup program gets run in addition to the program in this cgroup.
NONE and BPF_F_ALLOW_OVERRIDE existed before. This patch doesn't
change their behavior. It only clarifies the semantics in relation
to new flag.
Only one program is allowed to be attached to a cgroup with
NONE or BPF_F_ALLOW_OVERRIDE flag.
Multiple programs are allowed to be attached to a cgroup with
BPF_F_ALLOW_MULTI flag. They are executed in FIFO order
(those that were attached first, run first)
The programs of sub-cgroup are executed first, then programs of
this cgroup and then programs of parent cgroup.
All eligible programs are executed regardless of return code from
earlier programs.
To allow efficient execution of multiple programs attached to a cgroup
and to avoid penalizing cgroups without any programs attached
introduce 'struct bpf_prog_array' which is RCU protected array
of pointers to bpf programs.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
for cgroup bits
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
In order to be able to trace module init functions, the module code needs to
tell ftrace what is being freed when the init sections are freed. Use the
code that the main init calls to tell ftrace to free the main init sections.
This requires passing in a start and end address to free.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This tunable has been obsolete since 2.6.32, and writes to the
file have been failing and complaining in dmesg since then:
nr_pdflush_threads exported in /proc is scheduled for removal
That was 8 years ago. Remove the file ABI obsolete notice, and
the sysfs file.
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
log2 as currently implemented applies only to u64 trace_event_field
derived fields, and assumes that anything it's applied to is a u64
field.
To prepare for synthetic fields like latencies, log2 should be
applicable to those as well, so take the opportunity now to fix the
current problems as well as expand to more general uses.
log2 should be thought of as a chaining function rather than a field
type. To enable this as well as possible future function
implementations, add a hist_field operand array into the hist_field
definition for this purpose, and make use of it to implement the log2
'function'.
Link: http://lkml.kernel.org/r/b47f93fc0b87b36eccf716b0c018f3a71e1f1111.1506105045.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>
traceprobe_probes_write() and traceprobe_command() actually contain
nothing that ties them to kprobes - the code is generically useful for
similar types of parsing elsewhere, so separate it out and move it to
trace.c/trace.h.
Other than moving it, the only change is in naming:
traceprobe_probes_write() becomes trace_parse_run_command() and
traceprobe_command() becomes trace_run_command().
Link: http://lkml.kernel.org/r/ae5c26ea40c196a8986854d921eb6e713ede7e3f.1506105045.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>
Merge misc fixes from Andrew Morton:
"A lot of stuff, sorry about that. A week on a beach, then a bunch of
time catching up then more time letting it bake in -next. Shan't do
that again!"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (51 commits)
include/linux/fs.h: fix comment about struct address_space
checkpatch: fix ignoring cover-letter logic
m32r: fix build failure
lib/ratelimit.c: use deferred printk() version
kernel/params.c: improve STANDARD_PARAM_DEF readability
kernel/params.c: fix an overflow in param_attr_show
kernel/params.c: fix the maximum length in param_get_string
mm/memory_hotplug: define find_{smallest|biggest}_section_pfn as unsigned long
mm/memory_hotplug: change pfn_to_section_nr/section_nr_to_pfn macro to inline function
kernel/kcmp.c: drop branch leftover typo
memremap: add scheduling point to devm_memremap_pages
mm, page_alloc: add scheduling point to memmap_init_zone
mm, memory_hotplug: add scheduling point to __add_pages
lib/idr.c: fix comment for idr_replace()
mm: memcontrol: use vmalloc fallback for large kmem memcg arrays
kernel/sysctl.c: remove duplicate UINT_MAX check on do_proc_douintvec_conv()
include/linux/bitfield.h: remove 32bit from FIELD_GET comment block
lib/lz4: make arrays static const, reduces object code size
exec: binfmt_misc: kill the onstack iname[BINPRM_BUF_SIZE] array
exec: binfmt_misc: fix race between load_misc_binary() and kill_node()
...
The current method to prevent the ring buffer from entering into a recursize
loop is to use a bitmask and set the bit that maps to the current context
(normal, softirq, irq or NMI), and if that bit was already set, it is
considered a recursive loop.
New code is being added that may require the ring buffer to be entered a
second time in the current context. The recursive locking prevents that from
happening. Instead of mapping a bitmask to the current context, just allow 4
levels of nesting in the ring buffer. This matches the 4 context levels that
it can already nest. It is highly unlikely to have more than two levels,
thus it should be fine when we add the second entry into the ring buffer. If
that proves to be a problem, we can always up the number to 8.
An added benefit is that reading preempt_count() to get the current level
adds a very slight but noticeable overhead. This removes that need.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
In order to make future changes where we need to call
tracing_set_clock() from within an event command, the order of
trace_types_lock and event_mutex must be reversed, as the event command
will hold event_mutex and the trace_types_lock is taken from within
tracing_set_clock().
Link: http://lkml.kernel.org/r/20170921162249.0dde3dca@gandalf.local.home
Requested-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Pull tracing fixlets from Steven Rostedt:
"Two updates:
- A memory fix with left over code from spliting out ftrace_ops and
function graph tracer, where the function graph tracer could reset
the trampoline pointer, leaving the old trampoline not to be freed
(memory leak).
- The update to Paul's patch that added the unnecessary READ_ONCE().
This removes the unnecessary READ_ONCE() instead of having to
rebase the branch to update the patch that added it"
* tag 'trace-v4.14-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
rcu: Remove extraneous READ_ONCE()s from rcu_irq_{enter,exit}()
ftrace: Fix kmemleak in unregister_ftrace_graph
The function names made sense up to the point where the watchdog
(re)configuration was unified to use softlockup_reconfigure_threads() for
all configuration purposes. But that includes scenarios which solely
configure the nmi watchdog.
Rename softlockup_reconfigure_threads() and softlockup_init_threads() so
the function names match the functionality.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linuxfoundation.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Don Zickus <dzickus@redhat.com>
The rework of the core hotplug code triggers the WARN_ON in start_wd_cpu()
on powerpc because it is called multiple times for the boot CPU.
The first call is via:
start_wd_on_cpu+0x80/0x2f0
watchdog_nmi_reconfigure+0x124/0x170
softlockup_reconfigure_threads+0x110/0x130
lockup_detector_init+0xbc/0xe0
kernel_init_freeable+0x18c/0x37c
kernel_init+0x2c/0x160
ret_from_kernel_thread+0x5c/0xbc
And then again via the CPU hotplug registration:
start_wd_on_cpu+0x80/0x2f0
cpuhp_invoke_callback+0x194/0x620
cpuhp_thread_fun+0x7c/0x1b0
smpboot_thread_fn+0x290/0x2a0
kthread+0x168/0x1b0
ret_from_kernel_thread+0x5c/0xbc
This can be avoided by setting up the cpu hotplug state with nocalls and
move the initialization to the watchdog_nmi_probe() function. That
initializes the hotplug callbacks without invoking the callback and the
following core initialization function then configures the watchdog for the
online CPUs (in this case CPU0) via softlockup_reconfigure_threads().
Reported-and-tested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: linuxppc-dev@lists.ozlabs.org
Function param_attr_show could overflow the buffer it is operating on.
The buffer size is PAGE_SIZE, and the string returned by
attribute->param->ops->get is generated by scnprintf(buffer, PAGE_SIZE,
...) so it could be PAGE_SIZE - 1 long, with the terminating '\0' at the
very end of the buffer. Calling strcat(..., "\n") on this isn't safe, as
the '\0' will be replaced by '\n' (OK) and then another '\0' will be added
past the end of the buffer (not OK.)
Simply add the trailing '\n' when writing the attribute contents to the
buffer originally. This is safe, and also faster.
Credits to Teradata for discovering this issue.
Link: http://lkml.kernel.org/r/20170928162602.60c379c7@endymion
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
devm_memremap_pages is initializing struct pages in for_each_device_pfn
and that can take quite some time. We have even seen a soft lockup
triggering on a non preemptive kernel
NMI watchdog: BUG: soft lockup - CPU#61 stuck for 22s! [kworker/u641:11:1808]
[...]
RIP: 0010:[<ffffffff8118b6b7>] [<ffffffff8118b6b7>] devm_memremap_pages+0x327/0x430
[...]
Call Trace:
pmem_attach_disk+0x2fd/0x3f0 [nd_pmem]
nvdimm_bus_probe+0x64/0x110 [libnvdimm]
driver_probe_device+0x1f7/0x420
bus_for_each_drv+0x52/0x80
__device_attach+0xb0/0x130
bus_probe_device+0x87/0xa0
device_add+0x3fc/0x5f0
nd_async_device_register+0xe/0x40 [libnvdimm]
async_run_entry_fn+0x43/0x150
process_one_work+0x14e/0x410
worker_thread+0x116/0x490
kthread+0xc7/0xe0
ret_from_fork+0x3f/0x70
fix this by adding cond_resched every 1024 pages.
Link: http://lkml.kernel.org/r/20170918121410.24466-4-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Johannes Thumshirn <jthumshirn@suse.de>
Tested-by: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Dan Williams <dan.j.williams@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
