Commit Graph
28391 Commits
Author SHA1 Message Date
Greg Kroah-Hartman f21f7fa263 Merge tag 'trace-v4.19-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Steven writes:
  "Vaibhav Nagarnaik found that modifying the ring buffer size could cause
   a huge latency in the system because it does a while loop to free pages
   without releasing the CPU (on non preempt kernels). In a case where there
   are hundreds of thousands of pages to free it could actually cause a system
   stall. A properly place cond_resched() solves this issue."
2018-09-19 07:41:46 +02:00
Greg Kroah-Hartman 5211da9ca5 Merge gitolite.kernel.org:/pub/scm/linux/kernel/git/davem/net
Dave writes:
  "Various fixes, all over the place:

   1) OOB data generation fix in bluetooth, from Matias Karhumaa.

   2) BPF BTF boundary calculation fix, from Martin KaFai Lau.

   3) Don't bug on excessive frags, to be compatible in situations mixing
      older and newer kernels on each end.  From Juergen Gross.

   4) Scheduling in RCU fix in hv_netvsc, from Stephen Hemminger.

   5) Zero keying information in TLS layer before freeing copies
      of them, from Sabrina Dubroca.

   6) Fix NULL deref in act_sample, from Davide Caratti.

   7) Orphan SKB before GRO in veth to prevent crashes with XDP,
      from Toshiaki Makita.

   8) Fix use after free in ip6_xmit, from Eric Dumazet.

   9) Fix VF mac address regression in bnxt_en, from Micahel Chan.

   10) Fix MSG_PEEK behavior in TLS layer, from Daniel Borkmann.

   11) Programming adjustments to r8169 which fix not being to enter deep
       sleep states on some machines, from Kai-Heng Feng and Hans de
       Goede.

   12) Fix DST_NOCOUNT flag handling for ipv6 routes, from Peter
       Oskolkov."

* gitolite.kernel.org:/pub/scm/linux/kernel/git/davem/net: (45 commits)
  net/ipv6: do not copy dst flags on rt init
  qmi_wwan: set DTR for modems in forced USB2 mode
  clk: x86: Stop marking clocks as CLK_IS_CRITICAL
  r8169: Get and enable optional ether_clk clock
  clk: x86: add "ether_clk" alias for Bay Trail / Cherry Trail
  r8169: enable ASPM on RTL8106E
  r8169: Align ASPM/CLKREQ setting function with vendor driver
  Revert "kcm: remove any offset before parsing messages"
  kcm: remove any offset before parsing messages
  net: ethernet: Fix a unused function warning.
  net: dsa: mv88e6xxx: Fix ATU Miss Violation
  tls: fix currently broken MSG_PEEK behavior
  hv_netvsc: pair VF based on serial number
  PCI: hv: support reporting serial number as slot information
  bnxt_en: Fix VF mac address regression.
  ipv6: fix possible use-after-free in ip6_xmit()
  net: hp100: fix always-true check for link up state
  ARM: dts: at91: add new compatibility string for macb on sama5d3
  net: macb: disable scatter-gather for macb on sama5d3
  net: mvpp2: let phylink manage the carrier state
  ...
2018-09-18 09:31:53 +02:00
Vaibhav Nagarnaik 83f365554e ring-buffer: Allow for rescheduling when removing pages
When reducing ring buffer size, pages are removed by scheduling a work
item on each CPU for the corresponding CPU ring buffer. After the pages
are removed from ring buffer linked list, the pages are free()d in a
tight loop. The loop does not give up CPU until all pages are removed.
In a worst case behavior, when lot of pages are to be freed, it can
cause system stall.

After the pages are removed from the list, the free() can happen while
the work is rescheduled. Call cond_resched() in the loop to prevent the
system hangup.

Link: http://lkml.kernel.org/r/20180907223129.71994-1-vnagarnaik@google.com

Cc: stable@vger.kernel.org
Fixes: 83f40318da ("ring-buffer: Make removal of ring buffer pages atomic")
Reported-by: Jason Behmer <jbehmer@google.com>
Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-09-17 18:15:11 -04:00
David S. Miller 0376d5dce0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2018-09-16

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

The main changes are:

1) Fix end boundary calculation in BTF for the type section, from Martin.

2) Fix and revert subtraction of pointers that was accidentally allowed
   for unprivileged programs, from Alexei.

3) Fix bpf_msg_pull_data() helper by using __GFP_COMP in order to avoid
   a warning in linearizing sg pages into a single one for large allocs,
   from Tushar.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-16 17:47:03 -07:00
Linus Torvalds 4314daa55b 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: various scheduler metrics corner case fixes, a
  sched_features deadlock fix, and a topology fix for certain NUMA
  systems"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/fair: Fix kernel-doc notation warning
  sched/fair: Fix load_balance redo for !imbalance
  sched/fair: Fix scale_rt_capacity() for SMT
  sched/fair: Fix vruntime_normalized() for remote non-migration wakeup
  sched/pelt: Fix update_blocked_averages() for RT and DL classes
  sched/topology: Set correct NUMA topology type
  sched/debug: Fix potential deadlock when writing to sched_features
2018-09-15 08:00:37 -10:00
Linus Torvalds c0be92b5b1 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Mostly tooling fixes, but also breakpoint and x86 PMU driver fixes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  perf tools: Fix maps__find_symbol_by_name()
  tools headers uapi: Update tools's copy of linux/if_link.h
  tools headers uapi: Update tools's copy of linux/vhost.h
  tools headers uapi: Update tools's copies of kvm headers
  tools headers uapi: Update tools's copy of drm/drm.h
  tools headers uapi: Update tools's copy of asm-generic/unistd.h
  tools headers uapi: Update tools's copy of linux/perf_event.h
  perf/core: Force USER_DS when recording user stack data
  perf/UAPI: Clearly mark __PERF_SAMPLE_CALLCHAIN_EARLY as internal use
  perf/x86/intel: Add support/quirk for the MISPREDICT bit on Knights Landing CPUs
  perf annotate: Fix parsing aarch64 branch instructions after objdump update
  perf probe powerpc: Ignore SyS symbols irrespective of endianness
  perf event-parse: Use fixed size string for comms
  perf util: Fix bad memory access in trace info.
  perf tools: Streamline bpf examples and headers installation
  perf evsel: Fix potential null pointer dereference in perf_evsel__new_idx()
  perf arm64: Fix include path for asm-generic/unistd.h
  perf/hw_breakpoint: Simplify breakpoint enable in perf_event_modify_breakpoint
  perf/hw_breakpoint: Enable breakpoint in modify_user_hw_breakpoint
  perf/hw_breakpoint: Remove superfluous bp->attr.disabled = 0
  ...
2018-09-15 06:44:32 -10:00
Linus Torvalds ca062f8df5 Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixes from Ingo Molnar:
 "Misc fixes: liblockdep fixes and ww_mutex fixes"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/ww_mutex: Fix spelling mistake "cylic" -> "cyclic"
  locking/lockdep: Delete unnecessary #include
  tools/lib/lockdep: Add dummy task_struct state member
  tools/lib/lockdep: Add empty nmi.h
  tools/lib/lockdep: Update Sasha Levin email to MSFT
  jump_label: Fix typo in warning message
  locking/mutex: Fix mutex debug call and ww_mutex documentation
2018-09-15 06:39:09 -10:00
Linus Torvalds a06b0c82a0 Merge tag 'printk-for-4.19-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk
Pull printk fix from Petr Mladek:
 "Revert a commit that caused "quiet", "debug", and "loglevel" early
  parameters to be ignored for early boot messages"

* tag 'printk-for-4.19-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk:
  Revert "printk: make sure to print log on console."
2018-09-13 19:37:08 -10:00
Alexei Starovoitov dd066823db bpf/verifier: disallow pointer subtraction
Subtraction of pointers was accidentally allowed for unpriv programs
by commit 82abbf8d2f. Revert that part of commit.

Fixes: 82abbf8d2f ("bpf: do not allow root to mangle valid pointers")
Reported-by: Jann Horn <jannh@google.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-09-12 23:30:02 +02:00
Martin KaFai Lau 4b1c5d917d bpf: btf: Fix end boundary calculation for type section
The end boundary math for type section is incorrect in
btf_check_all_metas().  It just happens that hdr->type_off
is always 0 for now because there are only two sections
(type and string) and string section must be at the end (ensured
in btf_parse_str_sec).

However, type_off may not be 0 if a new section would be added later.
This patch fixes it.

Fixes: f80442a4cd ("bpf: btf: Change how section is supported in btf_header")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-09-12 22:00:23 +02:00
Petr Mladek a6ae928c25 Revert "printk: make sure to print log on console."
This reverts commit 375899cddc.

The visibility of early messages did not longer take into account
"quiet", "debug", and "loglevel" early parameters.

It would be possible to invalidate and recompute LOG_NOCONS flag
for the affected messages. But it would be hairy.

Instead this patch just reverts the problematic commit. We could
come up with a better solution for the original problem. For example,
we could simplify the logic and just mark messages that should always
be visible or always invisible on the console.

Also this patch reverts the related build fix commit ffaa619af1
("printk: Fix warning about unused suppress_message_printing").

Finally, this patch does not put back the unused LOG_NOCONS flag.

Link: http://lkml.kernel.org/r/20180910145747.emvfzv4mzlk5dfqk@pathway.suse.cz
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Maninder Singh <maninder1.s@samsung.com>
Reported-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-09-11 10:04:34 +02:00
Yabin Cui 02e184476e perf/core: Force USER_DS when recording user stack data
Perf can record user stack data in response to a synchronous request, such
as a tracepoint firing. If this happens under set_fs(KERNEL_DS), then we
end up reading user stack data using __copy_from_user_inatomic() under
set_fs(KERNEL_DS). I think this conflicts with the intention of using
set_fs(KERNEL_DS). And it is explicitly forbidden by hardware on ARM64
when both CONFIG_ARM64_UAO and CONFIG_ARM64_PAN are used.

So fix this by forcing USER_DS when recording user stack data.

Signed-off-by: Yabin Cui <yabinc@google.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 88b0193d94 ("perf/callchain: Force USER_DS when invoking perf_callchain_user()")
Link: http://lkml.kernel.org/r/20180823225935.27035-1-yabinc@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-09-10 14:01:46 +02:00
Colin Ian King 0b405c65ad locking/ww_mutex: Fix spelling mistake "cylic" -> "cyclic"
Trivial fix to spelling mistake in pr_err() error message

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-janitors@vger.kernel.org
Link: http://lkml.kernel.org/r/20180824112235.8842-1-colin.king@canonical.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-09-10 14:00:01 +02:00
Ben Hutchings dc5591a03f locking/lockdep: Delete unnecessary #include
Commit:

  c3bc8fd637 ("tracing: Centralize preemptirq tracepoints and unify their usage")

added the inclusion of <trace/events/preemptirq.h>.

liblockdep doesn't have a stub version of that header so now fails to build.

However, commit:

  bff1b208a5 ("tracing: Partial revert of "tracing: Centralize preemptirq tracepoints and unify their usage"")

removed the use of functions declared in that header. So delete the #include.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sasha Levin <alexander.levin@verizon.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Fixes: bff1b208a5 ("tracing: Partial revert of "tracing: Centralize ...")
Fixes: c3bc8fd637 ("tracing: Centralize preemptirq tracepoints ...")
Link: http://lkml.kernel.org/r/20180828203315.GD18030@decadent.org.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-09-10 13:48:25 +02:00
Randy Dunlap 882a78a9f3 sched/fair: Fix kernel-doc notation warning
Fix kernel-doc warning for missing 'flags' parameter description:

../kernel/sched/fair.c:3371: warning: Function parameter or member 'flags' not described in 'attach_entity_load_avg'

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: ea14b57e8a ("sched/cpufreq: Provide migration hint")
Link: http://lkml.kernel.org/r/cdda0d42-880d-4229-a9f7-5899c977a063@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-09-10 10:31:37 +02:00
Borislav Petkov da260fe123 jump_label: Fix typo in warning message
There's no 'allocatote' - use the next best thing: 'allocate' :-)

Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180907103521.31344-1-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-09-10 10:15:48 +02:00
Vincent Guittot bb3485c8ac sched/fair: Fix load_balance redo for !imbalance
It can happen that load_balance() finds a busiest group and then a
busiest rq but the calculated imbalance is in fact 0.

In such situation, detach_tasks() returns immediately and lets the
flag LBF_ALL_PINNED set. The busiest CPU is then wrongly assumed to
have pinned tasks and removed from the load balance mask. then, we
redo a load balance without the busiest CPU. This creates wrong load
balance situation and generates wrong task migration.

If the calculated imbalance is 0, it's useless to try to find a
busiest rq as no task will be migrated and we can return immediately.

This situation can happen with heterogeneous system or smp system when
RT tasks are decreasing the capacity of some CPUs.

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: jhugo@codeaurora.org
Link: http://lkml.kernel.org/r/1536306664-29827-1-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-09-10 10:13:49 +02:00
Vincent Guittot 287cdaac57 sched/fair: Fix scale_rt_capacity() for SMT
Since commit:

  523e979d31 ("sched/core: Use PELT for scale_rt_capacity()")

scale_rt_capacity() returns the remaining capacity and not a scale factor
to apply on cpu_capacity_orig. arch_scale_cpu() is directly called by
scale_rt_capacity() so we must take the sched_domain argument.

Reported-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 523e979d31 ("sched/core: Use PELT for scale_rt_capacity()")
Link: http://lkml.kernel.org/r/20180904093626.GA23936@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-09-10 10:13:47 +02:00
Steve Muckle d0cdb3ce88 sched/fair: Fix vruntime_normalized() for remote non-migration wakeup
When a task which previously ran on a given CPU is remotely queued to
wake up on that same CPU, there is a period where the task's state is
TASK_WAKING and its vruntime is not normalized. This is not accounted
for in vruntime_normalized() which will cause an error in the task's
vruntime if it is switched from the fair class during this time.

For example if it is boosted to RT priority via rt_mutex_setprio(),
rq->min_vruntime will not be subtracted from the task's vruntime but
it will be added again when the task returns to the fair class. The
task's vruntime will have been erroneously doubled and the effective
priority of the task will be reduced.

Note this will also lead to inflation of all vruntimes since the doubled
vruntime value will become the rq's min_vruntime when other tasks leave
the rq. This leads to repeated doubling of the vruntime and priority
penalty.

Fix this by recognizing a WAKING task's vruntime as normalized only if
sched_remote_wakeup is true. This indicates a migration, in which case
the vruntime would have been normalized in migrate_task_rq_fair().

Based on a similar patch from John Dias <joaodias@google.com>.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Steve Muckle <smuckle@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Chris Redpath <Chris.Redpath@arm.com>
Cc: John Dias <joaodias@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Miguel de Dios <migueldedios@google.com>
Cc: Morten Rasmussen <Morten.Rasmussen@arm.com>
Cc: Patrick Bellasi <Patrick.Bellasi@arm.com>
Cc: Paul Turner <pjt@google.com>
Cc: Quentin Perret <quentin.perret@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Todd Kjos <tkjos@google.com>
Cc: kernel-team@android.com
Fixes: b5179ac70d ("sched/fair: Prepare to fix fairness problems on migration")
Link: http://lkml.kernel.org/r/20180831224217.169476-1-smuckle@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-09-10 10:13:47 +02:00
Vincent Guittot 12b04875d6 sched/pelt: Fix update_blocked_averages() for RT and DL classes
update_blocked_averages() is called to periodiccally decay the stalled load
of idle CPUs and to sync all loads before running load balance.

When cfs rq is idle, it trigs a load balance during pick_next_task_fair()
in order to potentially pull tasks and to use this newly idle CPU. This
load balance happens whereas prev task from another class has not been put
and its utilization updated yet. This may lead to wrongly account running
time as idle time for RT or DL classes.

Test that no RT or DL task is running when updating their utilization in
update_blocked_averages().

We still update RT and DL utilization instead of simply skipping them to
make sure that all metrics are synced when used during load balance.

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 371bf42732 ("sched/rt: Add rt_rq utilization tracking")
Fixes: 3727e0e163 ("sched/dl: Add dl_rq utilization tracking")
Link: http://lkml.kernel.org/r/1535728975-22799-1-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-09-10 10:13:46 +02:00
Srikar Dronamraju e5e96fafd9 sched/topology: Set correct NUMA topology type
With the following commit:

  051f3ca02e ("sched/topology: Introduce NUMA identity node sched domain")

the scheduler introduced a new NUMA level. However this leads to the NUMA topology
on 2 node systems to not be marked as NUMA_DIRECT anymore.

After this commit, it gets reported as NUMA_BACKPLANE, because
sched_domains_numa_level is now 2 on 2 node systems.

Fix this by allowing setting systems that have up to 2 NUMA levels as
NUMA_DIRECT.

While here remove code that assumes that level can be 0.

Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andre Wild <wild@linux.vnet.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linuxppc-dev <linuxppc-dev@lists.ozlabs.org>
Fixes: 051f3ca02e "Introduce NUMA identity node sched domain"
Link: http://lkml.kernel.org/r/1533920419-17410-1-git-send-email-srikar@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-09-10 10:13:45 +02:00
Jiada Wang e73e81975f sched/debug: Fix potential deadlock when writing to sched_features
The following lockdep report can be triggered by writing to /sys/kernel/debug/sched_features:

  ======================================================
  WARNING: possible circular locking dependency detected
  4.18.0-rc6-00152-gcd3f77d74ac3-dirty #18 Not tainted
  ------------------------------------------------------
  sh/3358 is trying to acquire lock:
  000000004ad3989d (cpu_hotplug_lock.rw_sem){++++}, at: static_key_enable+0x14/0x30
  but task is already holding lock:
  00000000c1b31a88 (&sb->s_type->i_mutex_key#3){+.+.}, at: sched_feat_write+0x160/0x428
  which lock already depends on the new lock.
  the existing dependency chain (in reverse order) is:
  -> #3 (&sb->s_type->i_mutex_key#3){+.+.}:
         lock_acquire+0xb8/0x148
         down_write+0xac/0x140
         start_creating+0x5c/0x168
         debugfs_create_dir+0x18/0x220
         opp_debug_register+0x8c/0x120
         _add_opp_dev+0x104/0x1f8
         dev_pm_opp_get_opp_table+0x174/0x340
         _of_add_opp_table_v2+0x110/0x760
         dev_pm_opp_of_add_table+0x5c/0x240
         dev_pm_opp_of_cpumask_add_table+0x5c/0x100
         cpufreq_init+0x160/0x430
         cpufreq_online+0x1cc/0xe30
         cpufreq_add_dev+0x78/0x198
         subsys_interface_register+0x168/0x270
         cpufreq_register_driver+0x1c8/0x278
         dt_cpufreq_probe+0xdc/0x1b8
         platform_drv_probe+0xb4/0x168
         driver_probe_device+0x318/0x4b0
         __device_attach_driver+0xfc/0x1f0
         bus_for_each_drv+0xf8/0x180
         __device_attach+0x164/0x200
         device_initial_probe+0x10/0x18
         bus_probe_device+0x110/0x178
         device_add+0x6d8/0x908
         platform_device_add+0x138/0x3d8
         platform_device_register_full+0x1cc/0x1f8
         cpufreq_dt_platdev_init+0x174/0x1bc
         do_one_initcall+0xb8/0x310
         kernel_init_freeable+0x4b8/0x56c
         kernel_init+0x10/0x138
         ret_from_fork+0x10/0x18
  -> #2 (opp_table_lock){+.+.}:
         lock_acquire+0xb8/0x148
         __mutex_lock+0x104/0xf50
         mutex_lock_nested+0x1c/0x28
         _of_add_opp_table_v2+0xb4/0x760
         dev_pm_opp_of_add_table+0x5c/0x240
         dev_pm_opp_of_cpumask_add_table+0x5c/0x100
         cpufreq_init+0x160/0x430
         cpufreq_online+0x1cc/0xe30
         cpufreq_add_dev+0x78/0x198
         subsys_interface_register+0x168/0x270
         cpufreq_register_driver+0x1c8/0x278
         dt_cpufreq_probe+0xdc/0x1b8
         platform_drv_probe+0xb4/0x168
         driver_probe_device+0x318/0x4b0
         __device_attach_driver+0xfc/0x1f0
         bus_for_each_drv+0xf8/0x180
         __device_attach+0x164/0x200
         device_initial_probe+0x10/0x18
         bus_probe_device+0x110/0x178
         device_add+0x6d8/0x908
         platform_device_add+0x138/0x3d8
         platform_device_register_full+0x1cc/0x1f8
         cpufreq_dt_platdev_init+0x174/0x1bc
         do_one_initcall+0xb8/0x310
         kernel_init_freeable+0x4b8/0x56c
         kernel_init+0x10/0x138
         ret_from_fork+0x10/0x18
  -> #1 (subsys mutex#6){+.+.}:
         lock_acquire+0xb8/0x148
         __mutex_lock+0x104/0xf50
         mutex_lock_nested+0x1c/0x28
         subsys_interface_register+0xd8/0x270
         cpufreq_register_driver+0x1c8/0x278
         dt_cpufreq_probe+0xdc/0x1b8
         platform_drv_probe+0xb4/0x168
         driver_probe_device+0x318/0x4b0
         __device_attach_driver+0xfc/0x1f0
         bus_for_each_drv+0xf8/0x180
         __device_attach+0x164/0x200
         device_initial_probe+0x10/0x18
         bus_probe_device+0x110/0x178
         device_add+0x6d8/0x908
         platform_device_add+0x138/0x3d8
         platform_device_register_full+0x1cc/0x1f8
         cpufreq_dt_platdev_init+0x174/0x1bc
         do_one_initcall+0xb8/0x310
         kernel_init_freeable+0x4b8/0x56c
         kernel_init+0x10/0x138
         ret_from_fork+0x10/0x18
  -> #0 (cpu_hotplug_lock.rw_sem){++++}:
         __lock_acquire+0x203c/0x21d0
         lock_acquire+0xb8/0x148
         cpus_read_lock+0x58/0x1c8
         static_key_enable+0x14/0x30
         sched_feat_write+0x314/0x428
         full_proxy_write+0xa0/0x138
         __vfs_write+0xd8/0x388
         vfs_write+0xdc/0x318
         ksys_write+0xb4/0x138
         sys_write+0xc/0x18
         __sys_trace_return+0x0/0x4
  other info that might help us debug this:
  Chain exists of:
    cpu_hotplug_lock.rw_sem --> opp_table_lock --> &sb->s_type->i_mutex_key#3
   Possible unsafe locking scenario:
         CPU0                    CPU1
         ----                    ----
    lock(&sb->s_type->i_mutex_key#3);
                                 lock(opp_table_lock);
                                 lock(&sb->s_type->i_mutex_key#3);
    lock(cpu_hotplug_lock.rw_sem);
   *** DEADLOCK ***
  2 locks held by sh/3358:
   #0: 00000000a8c4b363 (sb_writers#10){.+.+}, at: vfs_write+0x238/0x318
   #1: 00000000c1b31a88 (&sb->s_type->i_mutex_key#3){+.+.}, at: sched_feat_write+0x160/0x428
  stack backtrace:
  CPU: 5 PID: 3358 Comm: sh Not tainted 4.18.0-rc6-00152-gcd3f77d74ac3-dirty #18
  Hardware name: Renesas H3ULCB Kingfisher board based on r8a7795 ES2.0+ (DT)
  Call trace:
   dump_backtrace+0x0/0x288
   show_stack+0x14/0x20
   dump_stack+0x13c/0x1ac
   print_circular_bug.isra.10+0x270/0x438
   check_prev_add.constprop.16+0x4dc/0xb98
   __lock_acquire+0x203c/0x21d0
   lock_acquire+0xb8/0x148
   cpus_read_lock+0x58/0x1c8
   static_key_enable+0x14/0x30
   sched_feat_write+0x314/0x428
   full_proxy_write+0xa0/0x138
   __vfs_write+0xd8/0x388
   vfs_write+0xdc/0x318
   ksys_write+0xb4/0x138
   sys_write+0xc/0x18
   __sys_trace_return+0x0/0x4

This is because when loading the cpufreq_dt module we first acquire
cpu_hotplug_lock.rw_sem lock, then in cpufreq_init(), we are taking
the &sb->s_type->i_mutex_key lock.

But when writing to /sys/kernel/debug/sched_features, the
cpu_hotplug_lock.rw_sem lock depends on the &sb->s_type->i_mutex_key lock.

To fix this bug, reverse the lock acquisition order when writing to
sched_features, this way cpu_hotplug_lock.rw_sem no longer depends on
&sb->s_type->i_mutex_key.

Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Eugeniu Rosca <erosca@de.adit-jv.com>
Cc: George G. Davis <george_davis@mentor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180731121222.26195-1-jiada_wang@mentor.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-09-10 10:13:45 +02:00
Thomas Hellstrom e13e2366d8 locking/mutex: Fix mutex debug call and ww_mutex documentation
The following commit:

  08295b3b5b ("Implement an algorithm choice for Wound-Wait mutexes")

introduced a reference in the documentation to a function that was
removed in an earlier commit.

It also forgot to remove a call to debug_mutex_add_waiter() which is now
unconditionally called by __mutex_add_waiter().

Fix those bugs.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dri-devel@lists.freedesktop.org
Fixes: 08295b3b5b ("Implement an algorithm choice for Wound-Wait mutexes")
Link: http://lkml.kernel.org/r/20180903140708.2401-1-thellstrom@vmware.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-09-10 10:05:10 +02:00
Ingo Molnar fa94351b56 Merge tag 'perf-urgent-for-mingo-4.19-20180903' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent
Pull perf/urgent fixes from Arnaldo Carvalho de Melo:

Kernel:

- Modify breakpoint fixes (Jiri Olsa)

perf annotate:

- Fix parsing aarch64 branch instructions after objdump update (Kim Phillips)

- Fix parsing indirect calls in 'perf annotate' (Martin Liška)

perf probe:

- Ignore SyS symbols irrespective of endianness on PowerPC (Sandipan Das)

perf trace:

- Fix include path for asm-generic/unistd.h on arm64 (Kim Phillips)

Core libraries:

- Fix potential null pointer dereference in perf_evsel__new_idx() (Hisao Tanabe)

- Use fixed size string for comms instead of scanf("%m"), that is
  not present in the bionic libc and leads to a crash (Chris Phlipot)

- Fix bad memory access in trace info on 32-bit systems, we were reading
  8 bytes from a 4-byte long variable when saving the command line in the
  perf.data file.  (Chris Phlipot)

Build system:

- Streamline bpf examples and headers installation, clarifying
  some install messages. (Arnaldo Carvalho de Melo)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-09-09 21:36:31 +02:00
Linus Torvalds 3567994a05 Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timekeeping fixes from Thomas Gleixner:
 "Two fixes for timekeeping:

   - Revert to the previous kthread based update, which is unfortunately
     required due to lock ordering issues. The removal caused boot
     failures on old Core2 machines. Add a proper comment why the thread
     needs to stay to prevent accidental removal in the future.

   - Fix a silly typo in a function declaration"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clocksource: Revert "Remove kthread"
  timekeeping: Fix declaration of read_persistent_wall_and_boot_offset()
2018-09-09 06:55:27 -07:00