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Author SHA1 Message Date
Linus Torvalds 26bc672134 for-linus-2019-11-05
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Merge tag 'for-linus-2019-11-05' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux

Pull clone3 stack argument update from Christian Brauner:
 "This changes clone3() to do basic stack validation and to set up the
  stack depending on whether or not it is growing up or down.

  With clone3() the expectation is now very simply that the .stack
  argument points to the lowest address of the stack and that
  .stack_size specifies the initial stack size. This is diferent from
  legacy clone() where the "stack" argument had to point to the lowest
  or highest address of the stack depending on the architecture.

  clone3() was released with 5.3. Currently, it is not documented and
  very unclear to userspace how the stack and stack_size argument have
  to be passed. After talking to glibc folks we concluded that changing
  clone3() to determine stack direction and doing basic validation is
  the right course of action.

  Note, this is a potentially user visible change. In the very unlikely
  case, that it breaks someone's use-case we will revert. (And then e.g.
  place the new behavior under an appropriate flag.)

  Note that passing an empty stack will continue working just as before.
  Breaking someone's use-case is very unlikely. Neither glibc nor musl
  currently expose a wrapper for clone3(). There is currently also no
  real motivation for anyone to use clone3() directly. First, because
  using clone{3}() with stacks requires some assembly (see glibc and
  musl). Second, because it does not provide features that legacy
  clone() doesn't. New features for clone3() will first happen in v5.5
  which is why v5.4 is still a good time to try and make that change now
  and backport it to v5.3.

  I did a codesearch on https://codesearch.debian.net, github, and
  gitlab and could not find any software currently relying directly on
  clone3(). I expect this to change once we land CLONE_CLEAR_SIGHAND
  which was a request coming from glibc at which point they'll likely
  start using it"

* tag 'for-linus-2019-11-05' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
  clone3: validate stack arguments
2019-11-05 09:44:02 -08:00
Christian Brauner fa729c4df5
clone3: validate stack arguments
Validate the stack arguments and setup the stack depening on whether or not
it is growing down or up.

Legacy clone() required userspace to know in which direction the stack is
growing and pass down the stack pointer appropriately. To make things more
confusing microblaze uses a variant of the clone() syscall selected by
CONFIG_CLONE_BACKWARDS3 that takes an additional stack_size argument.
IA64 has a separate clone2() syscall which also takes an additional
stack_size argument. Finally, parisc has a stack that is growing upwards.
Userspace therefore has a lot nasty code like the following:

 #define __STACK_SIZE (8 * 1024 * 1024)
 pid_t sys_clone(int (*fn)(void *), void *arg, int flags, int *pidfd)
 {
         pid_t ret;
         void *stack;

         stack = malloc(__STACK_SIZE);
         if (!stack)
                 return -ENOMEM;

 #ifdef __ia64__
         ret = __clone2(fn, stack, __STACK_SIZE, flags | SIGCHLD, arg, pidfd);
 #elif defined(__parisc__) /* stack grows up */
         ret = clone(fn, stack, flags | SIGCHLD, arg, pidfd);
 #else
         ret = clone(fn, stack + __STACK_SIZE, flags | SIGCHLD, arg, pidfd);
 #endif
         return ret;
 }

or even crazier variants such as [3].

With clone3() we have the ability to validate the stack. We can check that
when stack_size is passed, the stack pointer is valid and the other way
around. We can also check that the memory area userspace gave us is fine to
use via access_ok(). Furthermore, we probably should not require
userspace to know in which direction the stack is growing. It is easy
for us to do this in the kernel and I couldn't find the original
reasoning behind exposing this detail to userspace.

/* Intentional user visible API change */
clone3() was released with 5.3. Currently, it is not documented and very
unclear to userspace how the stack and stack_size argument have to be
passed. After talking to glibc folks we concluded that trying to change
clone3() to setup the stack instead of requiring userspace to do this is
the right course of action.
Note, that this is an explicit change in user visible behavior we introduce
with this patch. If it breaks someone's use-case we will revert! (And then
e.g. place the new behavior under an appropriate flag.)
Breaking someone's use-case is very unlikely though. First, neither glibc
nor musl currently expose a wrapper for clone3(). Second, there is no real
motivation for anyone to use clone3() directly since it does not provide
features that legacy clone doesn't. New features for clone3() will first
happen in v5.5 which is why v5.4 is still a good time to try and make that
change now and backport it to v5.3. Searches on [4] did not reveal any
packages calling clone3().

[1]: https://lore.kernel.org/r/CAG48ez3q=BeNcuVTKBN79kJui4vC6nw0Bfq6xc-i0neheT17TA@mail.gmail.com
[2]: https://lore.kernel.org/r/20191028172143.4vnnjpdljfnexaq5@wittgenstein
[3]: 5238e95759/src/basic/raw-clone.h (L31)
[4]: https://codesearch.debian.net
Fixes: 7f192e3cd3 ("fork: add clone3")
Cc: Kees Cook <keescook@chromium.org>
Cc: Jann Horn <jannh@google.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-api@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: <stable@vger.kernel.org> # 5.3
Cc: GNU C Library <libc-alpha@sourceware.org>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Aleksa Sarai <cyphar@cyphar.com>
Link: https://lore.kernel.org/r/20191031113608.20713-1-christian.brauner@ubuntu.com
2019-11-05 15:50:14 +01:00
Linus Torvalds 1204c70d9d Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from David Miller:

 1) Fix free/alloc races in batmanadv, from Sven Eckelmann.

 2) Several leaks and other fixes in kTLS support of mlx5 driver, from
    Tariq Toukan.

 3) BPF devmap_hash cost calculation can overflow on 32-bit, from Toke
    Høiland-Jørgensen.

 4) Add an r8152 device ID, from Kazutoshi Noguchi.

 5) Missing include in ipv6's addrconf.c, from Ben Dooks.

 6) Use siphash in flow dissector, from Eric Dumazet. Attackers can
    easily infer the 32-bit secret otherwise etc.

 7) Several netdevice nesting depth fixes from Taehee Yoo.

 8) Fix several KCSAN reported errors, from Eric Dumazet. For example,
    when doing lockless skb_queue_empty() checks, and accessing
    sk_napi_id/sk_incoming_cpu lockless as well.

 9) Fix jumbo packet handling in RXRPC, from David Howells.

10) Bump SOMAXCONN and tcp_max_syn_backlog values, from Eric Dumazet.

11) Fix DMA synchronization in gve driver, from Yangchun Fu.

12) Several bpf offload fixes, from Jakub Kicinski.

13) Fix sk_page_frag() recursion during memory reclaim, from Tejun Heo.

14) Fix ping latency during high traffic rates in hisilicon driver, from
    Jiangfent Xiao.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (146 commits)
  net: fix installing orphaned programs
  net: cls_bpf: fix NULL deref on offload filter removal
  selftests: bpf: Skip write only files in debugfs
  selftests: net: reuseport_dualstack: fix uninitalized parameter
  r8169: fix wrong PHY ID issue with RTL8168dp
  net: dsa: bcm_sf2: Fix IMP setup for port different than 8
  net: phylink: Fix phylink_dbg() macro
  gve: Fixes DMA synchronization.
  inet: stop leaking jiffies on the wire
  ixgbe: Remove duplicate clear_bit() call
  Documentation: networking: device drivers: Remove stray asterisks
  e1000: fix memory leaks
  i40e: Fix receive buffer starvation for AF_XDP
  igb: Fix constant media auto sense switching when no cable is connected
  net: ethernet: arc: add the missed clk_disable_unprepare
  igb: Enable media autosense for the i350.
  igb/igc: Don't warn on fatal read failures when the device is removed
  tcp: increase tcp_max_syn_backlog max value
  net: increase SOMAXCONN to 4096
  netdevsim: Fix use-after-free during device dismantle
  ...
2019-11-01 17:48:11 -07:00
Linus Torvalds 0dbe6cb8f7 Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
 "Fix two scheduler topology bugs/oversights on Juno r0 2+4 big.LITTLE
  systems"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/topology: Allow sched_asym_cpucapacity to be disabled
  sched/topology: Don't try to build empty sched domains
2019-11-01 11:49:54 -07:00
Valentin Schneider e284df705c sched/topology: Allow sched_asym_cpucapacity to be disabled
While the static key is correctly initialized as being disabled, it will
remain forever enabled once turned on. This means that if we start with an
asymmetric system and hotplug out enough CPUs to end up with an SMP system,
the static key will remain set - which is obviously wrong. We should detect
this and turn off things like misfit migration and capacity aware wakeups.

As Quentin pointed out, having separate root domains makes this slightly
trickier. We could have exclusive cpusets that create an SMP island - IOW,
the domains within this root domain will not see any asymmetry. This means
we can't just disable the key on domain destruction, we need to count how
many asymmetric root domains we have.

Consider the following example using Juno r0 which is 2+4 big.LITTLE, where
two identical cpusets are created: they both span both big and LITTLE CPUs:

    asym0    asym1
  [       ][       ]
   L  L  B  L  L  B

  $ cgcreate -g cpuset:asym0
  $ cgset -r cpuset.cpus=0,1,3 asym0
  $ cgset -r cpuset.mems=0 asym0
  $ cgset -r cpuset.cpu_exclusive=1 asym0

  $ cgcreate -g cpuset:asym1
  $ cgset -r cpuset.cpus=2,4,5 asym1
  $ cgset -r cpuset.mems=0 asym1
  $ cgset -r cpuset.cpu_exclusive=1 asym1

  $ cgset -r cpuset.sched_load_balance=0 .

(the CPU numbering may look odd because on the Juno LITTLEs are CPUs 0,3-5
and bigs are CPUs 1-2)

If we make one of those SMP (IOW remove asymmetry) by e.g. hotplugging its
big core, we would end up with an SMP cpuset and an asymmetric cpuset - the
static key must remain set, because we still have one asymmetric root domain.

With the above example, this could be done with:

  $ echo 0 > /sys/devices/system/cpu/cpu2/online

Which would result in:

    asym0   asym1
  [       ][    ]
   L  L  B  L  L

When both SMP and asymmetric cpusets are present, all CPUs will observe
sched_asym_cpucapacity being set (it is system-wide), but not all CPUs
observe asymmetry in their sched domain hierarchy:

  per_cpu(sd_asym_cpucapacity, <any CPU in asym0>) == <some SD at DIE level>
  per_cpu(sd_asym_cpucapacity, <any CPU in asym1>) == NULL

Change the simple key enablement to an increment, and decrement the key
counter when destroying domains that cover asymmetric CPUs.

Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Dietmar.Eggemann@arm.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: hannes@cmpxchg.org
Cc: lizefan@huawei.com
Cc: morten.rasmussen@arm.com
Cc: qperret@google.com
Cc: tj@kernel.org
Cc: vincent.guittot@linaro.org
Fixes: df054e8445 ("sched/topology: Add static_key for asymmetric CPU capacity optimizations")
Link: https://lkml.kernel.org/r/20191023153745.19515-3-valentin.schneider@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-29 09:58:46 +01:00
Valentin Schneider cd1cb33505 sched/topology: Don't try to build empty sched domains
Turns out hotplugging CPUs that are in exclusive cpusets can lead to the
cpuset code feeding empty cpumasks to the sched domain rebuild machinery.

This leads to the following splat:

    Internal error: Oops: 96000004 [#1] PREEMPT SMP
    Modules linked in:
    CPU: 0 PID: 235 Comm: kworker/5:2 Not tainted 5.4.0-rc1-00005-g8d495477d62e #23
    Hardware name: ARM Juno development board (r0) (DT)
    Workqueue: events cpuset_hotplug_workfn
    pstate: 60000005 (nZCv daif -PAN -UAO)
    pc : build_sched_domains (./include/linux/arch_topology.h:23 kernel/sched/topology.c:1898 kernel/sched/topology.c:1969)
    lr : build_sched_domains (kernel/sched/topology.c:1966)
    Call trace:
    build_sched_domains (./include/linux/arch_topology.h:23 kernel/sched/topology.c:1898 kernel/sched/topology.c:1969)
    partition_sched_domains_locked (kernel/sched/topology.c:2250)
    rebuild_sched_domains_locked (./include/linux/bitmap.h:370 ./include/linux/cpumask.h:538 kernel/cgroup/cpuset.c:955 kernel/cgroup/cpuset.c:978 kernel/cgroup/cpuset.c:1019)
    rebuild_sched_domains (kernel/cgroup/cpuset.c:1032)
    cpuset_hotplug_workfn (kernel/cgroup/cpuset.c:3205 (discriminator 2))
    process_one_work (./arch/arm64/include/asm/jump_label.h:21 ./include/linux/jump_label.h:200 ./include/trace/events/workqueue.h:114 kernel/workqueue.c:2274)
    worker_thread (./include/linux/compiler.h:199 ./include/linux/list.h:268 kernel/workqueue.c:2416)
    kthread (kernel/kthread.c:255)
    ret_from_fork (arch/arm64/kernel/entry.S:1167)
    Code: f860dae2 912802d6 aa1603e1 12800000 (f8616853)

The faulty line in question is:

  cap = arch_scale_cpu_capacity(cpumask_first(cpu_map));

and we're not checking the return value against nr_cpu_ids (we shouldn't
have to!), which leads to the above.

Prevent generate_sched_domains() from returning empty cpumasks, and add
some assertion in build_sched_domains() to scream bloody murder if it
happens again.

The above splat was obtained on my Juno r0 with the following reproducer:

  $ cgcreate -g cpuset:asym
  $ cgset -r cpuset.cpus=0-3 asym
  $ cgset -r cpuset.mems=0 asym
  $ cgset -r cpuset.cpu_exclusive=1 asym

  $ cgcreate -g cpuset:smp
  $ cgset -r cpuset.cpus=4-5 smp
  $ cgset -r cpuset.mems=0 smp
  $ cgset -r cpuset.cpu_exclusive=1 smp

  $ cgset -r cpuset.sched_load_balance=0 .

  $ echo 0 > /sys/devices/system/cpu/cpu4/online
  $ echo 0 > /sys/devices/system/cpu/cpu5/online

Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Dietmar.Eggemann@arm.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: hannes@cmpxchg.org
Cc: lizefan@huawei.com
Cc: morten.rasmussen@arm.com
Cc: qperret@google.com
Cc: tj@kernel.org
Cc: vincent.guittot@linaro.org
Fixes: 05484e0984 ("sched/topology: Add SD_ASYM_CPUCAPACITY flag detection")
Link: https://lkml.kernel.org/r/20191023153745.19515-2-valentin.schneider@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-29 09:58:45 +01:00
Alexander Shishkin 8c7e975667 perf/core: Start rejecting the syscall with attr.__reserved_2 set
Commit:

  1a59413124 ("perf: Add wakeup watermark control to the AUX area")

added attr.__reserved_2 padding, but forgot to add an ABI check to reject
attributes with this field set. Fix that.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: adrian.hunter@intel.com
Cc: mathieu.poirier@linaro.org
Link: https://lkml.kernel.org/r/20191025121636.75182-1-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-28 11:01:59 +01:00
Linus Torvalds 2b776b54bc 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 for time(keeping):

   - Add a missing include to prevent compiler warnings.

   - Make the VDSO implementation of clock_getres() POSIX compliant
     again. A recent change dropped the NULL pointer guard which is
     required as NULL is a valid pointer value for this function.

   - Fix two function documentation typos"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  posix-cpu-timers: Fix two trivial comments
  timers/sched_clock: Include local timekeeping.h for missing declarations
  lib/vdso: Make clock_getres() POSIX compliant again
2019-10-27 07:04:22 -04:00
Linus Torvalds a8a31fdcca Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Thomas Gleixner:
 "A set of perf fixes:

  kernel:

   - Unbreak the tracking of auxiliary buffer allocations which got
     imbalanced causing recource limit failures.

   - Fix the fallout of splitting of ToPA entries which missed to shift
     the base entry PA correctly.

   - Use the correct context to lookup the AUX event when unmapping the
     associated AUX buffer so the event can be stopped and the buffer
     reference dropped.

  tools:

   - Fix buildiid-cache mode setting in copyfile_mode_ns() when copying
     /proc/kcore

   - Fix freeing id arrays in the event list so the correct event is
     closed.

   - Sync sched.h anc kvm.h headers with the kernel sources.

   - Link jvmti against tools/lib/ctype.o to have weak strlcpy().

   - Fix multiple memory and file descriptor leaks, found by coverity in
     perf annotate.

   - Fix leaks in error handling paths in 'perf c2c', 'perf kmem', found
     by a static analysis tool"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/aux: Fix AUX output stopping
  perf/aux: Fix tracking of auxiliary trace buffer allocation
  perf/x86/intel/pt: Fix base for single entry topa
  perf kmem: Fix memory leak in compact_gfp_flags()
  tools headers UAPI: Sync sched.h with the kernel
  tools headers kvm: Sync kvm.h headers with the kernel sources
  tools headers kvm: Sync kvm headers with the kernel sources
  tools headers kvm: Sync kvm headers with the kernel sources
  perf c2c: Fix memory leak in build_cl_output()
  perf tools: Fix mode setting in copyfile_mode_ns()
  perf annotate: Fix multiple memory and file descriptor leaks
  perf tools: Fix resource leak of closedir() on the error paths
  perf evlist: Fix fix for freed id arrays
  perf jvmti: Link against tools/lib/ctype.h to have weak strlcpy()
2019-10-27 06:59:34 -04:00
David S. Miller 1a51a47491 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2019-10-27

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

We've added 7 non-merge commits during the last 11 day(s) which contain
a total of 7 files changed, 66 insertions(+), 16 deletions(-).

The main changes are:

1) Fix two use-after-free bugs in relation to RCU in jited symbol exposure to
   kallsyms, from Daniel Borkmann.

2) Fix NULL pointer dereference in AF_XDP rx-only sockets, from Magnus Karlsson.

3) Fix hang in netdev unregister for hash based devmap as well as another overflow
   bug on 32 bit archs in memlock cost calculation, from Toke Høiland-Jørgensen.

4) Fix wrong memory access in LWT BPF programs on reroute due to invalid dst.
   Also fix BPF selftests to use more compatible nc options, from Jiri Benc.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-26 18:30:55 -07:00
Linus Torvalds 5fa2845fd7 Power management fixes for 5.4-rc5
- Using device PM QoS of CPU devices for managing frequency limits
    in cpufreq does not work, so introduce frequency QoS (based on the
    original low-level PM QoS) for this purpose, switch cpufreq and
    related code over to using it and fix a race involving deferred
    updates of frequency limits on top of that (Rafael Wysocki, Sudeep
    Holla).
 
  - Avoid calling regulator_enable()/disable() from the OPP framework
    to avoid side-effects on boot-enabled regulators that may change their
    initial voltage due to performing initial voltage balancing without
    all restrictions from the consumers (Marek Szyprowski).
 
  - Avoid a kref management issue in the OPP library code and drop an
    incorrectly added lockdep_assert_held() from it (Viresh Kumar).
 
  - Make the recently added haltpoll cpuidle driver take the 'idle='
    override into account as appropriate (Zhenzhong Duan).
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Merge tag 'pm-5.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management fixes from Rafael Wysocki:
 "These fix problems related to frequency limits management in cpufreq
  that were introduced during the 5.3 cycle (when PM QoS had started to
  be used for that), fix a few issues in the OPP (operating performance
  points) library code and fix up the recently added haltpoll cpuidle
  driver.

  The cpufreq changes are somewhat bigger that I would like them to be
  at this stage of the cycle, but the problems fixed by them include
  crashes on boot and shutdown in some cases (among other things) and in
  my view it is better to address the root of the issue right away.

  Specifics:

   - Using device PM QoS of CPU devices for managing frequency limits in
     cpufreq does not work, so introduce frequency QoS (based on the
     original low-level PM QoS) for this purpose, switch cpufreq and
     related code over to using it and fix a race involving deferred
     updates of frequency limits on top of that (Rafael Wysocki, Sudeep
     Holla).

   - Avoid calling regulator_enable()/disable() from the OPP framework
     to avoid side-effects on boot-enabled regulators that may change
     their initial voltage due to performing initial voltage balancing
     without all restrictions from the consumers (Marek Szyprowski).

   - Avoid a kref management issue in the OPP library code and drop an
     incorrectly added lockdep_assert_held() from it (Viresh Kumar).

   - Make the recently added haltpoll cpuidle driver take the 'idle='
     override into account as appropriate (Zhenzhong Duan)"

* tag 'pm-5.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  opp: Reinitialize the list_kref before adding the static OPPs again
  cpufreq: Cancel policy update work scheduled before freeing
  cpuidle: haltpoll: Take 'idle=' override into account
  opp: core: Revert "add regulators enable and disable"
  PM: QoS: Drop frequency QoS types from device PM QoS
  cpufreq: Use per-policy frequency QoS
  PM: QoS: Introduce frequency QoS
  opp: of: drop incorrect lockdep_assert_held()
2019-10-24 15:36:11 -04:00
Linus Torvalds fa8a74de06 Two minor fixes:
- A race in perf trace initialization (missing mutexes)
 
  - Minor fix to represent gfp_t in synthetic events as properly signed
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Merge tag 'trace-v5.4-rc3-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "Two minor fixes:

   - A race in perf trace initialization (missing mutexes)

   - Minor fix to represent gfp_t in synthetic events as properly
     signed"

* tag 'trace-v5.4-rc3-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix race in perf_trace_buf initialization
  tracing: Fix "gfp_t" format for synthetic events
2019-10-23 15:43:51 -04:00
Yi Wang 7f2cbcbcaf posix-cpu-timers: Fix two trivial comments
Recent changes modified the function arguments of
thread_group_sample_cputime() and task_cputimers_expired(), but forgot to
update the comments. Fix it up.

[ tglx: Changed the argument name of task_cputimers_expired() as the pointer
  	points to an array of samples. ]

Fixes: b7be4ef136 ("posix-cpu-timers: Switch thread group sampling to array")
Fixes: 001f797143 ("posix-cpu-timers: Make expiry checks array based")
Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/1571643852-21848-1-git-send-email-wang.yi59@zte.com.cn
2019-10-23 14:48:24 +02:00
Ben Dooks (Codethink) 086ee46b08 timers/sched_clock: Include local timekeeping.h for missing declarations
Include the timekeeping.h header to get the declaration of the
sched_clock_{suspend,resume} functions. Fixes the following sparse
warnings:

kernel/time/sched_clock.c:275:5: warning: symbol 'sched_clock_suspend' was not declared. Should it be static?
kernel/time/sched_clock.c:286:6: warning: symbol 'sched_clock_resume' was not declared. Should it be static?

Signed-off-by: Ben Dooks (Codethink) <ben.dooks@codethink.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191022131226.11465-1-ben.dooks@codethink.co.uk
2019-10-23 14:48:23 +02:00
Daniel Borkmann 3b4d9eb2ee bpf: Fix use after free in bpf_get_prog_name
There is one more problematic case I noticed while recently fixing BPF kallsyms
handling in cd7455f101 ("bpf: Fix use after free in subprog's jited symbol
removal") and that is bpf_get_prog_name().

If BTF has been attached to the prog, then we may be able to fetch the function
signature type id in kallsyms through prog->aux->func_info[prog->aux->func_idx].type_id.
However, while the BTF object itself is torn down via RCU callback, the prog's
aux->func_info is immediately freed via kvfree(prog->aux->func_info) once the
prog's refcount either hit zero or when subprograms were already exposed via
kallsyms and we hit the error path added in 5482e9a93c ("bpf: Fix memleak in
aux->func_info and aux->btf").

This violates RCU as well since kallsyms could be walked in parallel where we
could access aux->func_info. Hence, defer kvfree() to after RCU grace period.
Looking at ba64e7d852 ("bpf: btf: support proper non-jit func info") there
is no reason/dependency where we couldn't defer the kvfree(aux->func_info) into
the RCU callback.

Fixes: 5482e9a93c ("bpf: Fix memleak in aux->func_info and aux->btf")
Fixes: ba64e7d852 ("bpf: btf: support proper non-jit func info")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/875f2906a7c1a0691f2d567b4d8e4ea2739b1e88.1571779205.git.daniel@iogearbox.net
2019-10-22 21:59:49 -07:00
Daniel Borkmann cd7455f101 bpf: Fix use after free in subprog's jited symbol removal
syzkaller managed to trigger the following crash:

  [...]
  BUG: unable to handle page fault for address: ffffc90001923030
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD aa551067 P4D aa551067 PUD aa552067 PMD a572b067 PTE 80000000a1173163
  Oops: 0000 [#1] PREEMPT SMP KASAN
  CPU: 0 PID: 7982 Comm: syz-executor912 Not tainted 5.4.0-rc3+ #0
  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
  RIP: 0010:bpf_jit_binary_hdr include/linux/filter.h:787 [inline]
  RIP: 0010:bpf_get_prog_addr_region kernel/bpf/core.c:531 [inline]
  RIP: 0010:bpf_tree_comp kernel/bpf/core.c:600 [inline]
  RIP: 0010:__lt_find include/linux/rbtree_latch.h:115 [inline]
  RIP: 0010:latch_tree_find include/linux/rbtree_latch.h:208 [inline]
  RIP: 0010:bpf_prog_kallsyms_find kernel/bpf/core.c:674 [inline]
  RIP: 0010:is_bpf_text_address+0x184/0x3b0 kernel/bpf/core.c:709
  [...]
  Call Trace:
   kernel_text_address kernel/extable.c:147 [inline]
   __kernel_text_address+0x9a/0x110 kernel/extable.c:102
   unwind_get_return_address+0x4c/0x90 arch/x86/kernel/unwind_frame.c:19
   arch_stack_walk+0x98/0xe0 arch/x86/kernel/stacktrace.c:26
   stack_trace_save+0xb6/0x150 kernel/stacktrace.c:123
   save_stack mm/kasan/common.c:69 [inline]
   set_track mm/kasan/common.c:77 [inline]
   __kasan_kmalloc+0x11c/0x1b0 mm/kasan/common.c:510
   kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:518
   slab_post_alloc_hook mm/slab.h:584 [inline]
   slab_alloc mm/slab.c:3319 [inline]
   kmem_cache_alloc+0x1f5/0x2e0 mm/slab.c:3483
   getname_flags+0xba/0x640 fs/namei.c:138
   getname+0x19/0x20 fs/namei.c:209
   do_sys_open+0x261/0x560 fs/open.c:1091
   __do_sys_open fs/open.c:1115 [inline]
   __se_sys_open fs/open.c:1110 [inline]
   __x64_sys_open+0x87/0x90 fs/open.c:1110
   do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:290
   entry_SYSCALL_64_after_hwframe+0x49/0xbe
  [...]

After further debugging it turns out that we walk kallsyms while in parallel
we tear down a BPF program which contains subprograms that have been JITed
though the program itself has not been fully exposed and is eventually bailing
out with error.

The bpf_prog_kallsyms_del_subprogs() in bpf_prog_load()'s error path removes
the symbols, however, bpf_prog_free() tears down the JIT memory too early via
scheduled work. Instead, it needs to properly respect RCU grace period as the
kallsyms walk for BPF is under RCU.

Fix it by refactoring __bpf_prog_put()'s tear down and reuse it in our error
path where we defer final destruction when we have subprogs in the program.

Fixes: 7d1982b4e3 ("bpf: fix panic in prog load calls cleanup")
Fixes: 1c2a088a66 ("bpf: x64: add JIT support for multi-function programs")
Reported-by: syzbot+710043c5d1d5b5013bc7@syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: syzbot+710043c5d1d5b5013bc7@syzkaller.appspotmail.com
Link: https://lore.kernel.org/bpf/55f6367324c2d7e9583fa9ccf5385dcbba0d7a6e.1571752452.git.daniel@iogearbox.net
2019-10-22 11:26:09 -07:00
Alexander Shishkin f3a519e4ad perf/aux: Fix AUX output stopping
Commit:

  8a58ddae23 ("perf/core: Fix exclusive events' grouping")

allows CAP_EXCLUSIVE events to be grouped with other events. Since all
of those also happen to be AUX events (which is not the case the other
way around, because arch/s390), this changes the rules for stopping the
output: the AUX event may not be on its PMU's context any more, if it's
grouped with a HW event, in which case it will be on that HW event's
context instead. If that's the case, munmap() of the AUX buffer can't
find and stop the AUX event, potentially leaving the last reference with
the atomic context, which will then end up freeing the AUX buffer. This
will then trip warnings:

Fix this by using the context's PMU context when looking for events
to stop, instead of the event's PMU context.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20191022073940.61814-1-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-22 14:39:37 +02:00
Prateek Sood 6b1340cc00 tracing: Fix race in perf_trace_buf initialization
A race condition exists while initialiazing perf_trace_buf from
perf_trace_init() and perf_kprobe_init().

      CPU0                                        CPU1
perf_trace_init()
  mutex_lock(&event_mutex)
    perf_trace_event_init()
      perf_trace_event_reg()
        total_ref_count == 0
	buf = alloc_percpu()
        perf_trace_buf[i] = buf
        tp_event->class->reg() //fails       perf_kprobe_init()
	goto fail                              perf_trace_event_init()
                                                 perf_trace_event_reg()
        fail:
	  total_ref_count == 0

                                                   total_ref_count == 0
                                                   buf = alloc_percpu()
                                                   perf_trace_buf[i] = buf
                                                   tp_event->class->reg()
                                                   total_ref_count++

          free_percpu(perf_trace_buf[i])
          perf_trace_buf[i] = NULL

Any subsequent call to perf_trace_event_reg() will observe total_ref_count > 0,
causing the perf_trace_buf to be always NULL. This can result in perf_trace_buf
getting accessed from perf_trace_buf_alloc() without being initialized. Acquiring
event_mutex in perf_kprobe_init() before calling perf_trace_event_init() should
fix this race.

The race caused the following bug:

 Unable to handle kernel paging request at virtual address 0000003106f2003c
 Mem abort info:
   ESR = 0x96000045
   Exception class = DABT (current EL), IL = 32 bits
   SET = 0, FnV = 0
   EA = 0, S1PTW = 0
 Data abort info:
   ISV = 0, ISS = 0x00000045
   CM = 0, WnR = 1
 user pgtable: 4k pages, 39-bit VAs, pgdp = ffffffc034b9b000
 [0000003106f2003c] pgd=0000000000000000, pud=0000000000000000
 Internal error: Oops: 96000045 [#1] PREEMPT SMP
 Process syz-executor (pid: 18393, stack limit = 0xffffffc093190000)
 pstate: 80400005 (Nzcv daif +PAN -UAO)
 pc : __memset+0x20/0x1ac
 lr : memset+0x3c/0x50
 sp : ffffffc09319fc50

  __memset+0x20/0x1ac
  perf_trace_buf_alloc+0x140/0x1a0
  perf_trace_sys_enter+0x158/0x310
  syscall_trace_enter+0x348/0x7c0
  el0_svc_common+0x11c/0x368
  el0_svc_handler+0x12c/0x198
  el0_svc+0x8/0xc

Ramdumps showed the following:
  total_ref_count = 3
  perf_trace_buf = (
      0x0 -> NULL,
      0x0 -> NULL,
      0x0 -> NULL,
      0x0 -> NULL)

Link: http://lkml.kernel.org/r/1571120245-4186-1-git-send-email-prsood@codeaurora.org

Cc: stable@vger.kernel.org
Fixes: e12f03d703 ("perf/core: Implement the 'perf_kprobe' PMU")
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Prateek Sood <prsood@codeaurora.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-21 19:38:28 -04:00
Toke Høiland-Jørgensen ce197d83a9 xdp: Handle device unregister for devmap_hash map type
It seems I forgot to add handling of devmap_hash type maps to the device
unregister hook for devmaps. This omission causes devices to not be
properly released, which causes hangs.

Fix this by adding the missing handler.

Fixes: 6f9d451ab1 ("xdp: Add devmap_hash map type for looking up devices by hashed index")
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20191019111931.2981954-1-toke@redhat.com
2019-10-21 15:51:41 -07:00
Thomas Richter 5e6c3c7b1e perf/aux: Fix tracking of auxiliary trace buffer allocation
The following commit from the v5.4 merge window:

  d44248a413 ("perf/core: Rework memory accounting in perf_mmap()")

... breaks auxiliary trace buffer tracking.

If I run command 'perf record -e rbd000' to record samples and saving
them in the **auxiliary** trace buffer then the value of 'locked_vm' becomes
negative after all trace buffers have been allocated and released:

During allocation the values increase:

  [52.250027] perf_mmap user->locked_vm:0x87 pinned_vm:0x0 ret:0
  [52.250115] perf_mmap user->locked_vm:0x107 pinned_vm:0x0 ret:0
  [52.250251] perf_mmap user->locked_vm:0x188 pinned_vm:0x0 ret:0
  [52.250326] perf_mmap user->locked_vm:0x208 pinned_vm:0x0 ret:0
  [52.250441] perf_mmap user->locked_vm:0x289 pinned_vm:0x0 ret:0
  [52.250498] perf_mmap user->locked_vm:0x309 pinned_vm:0x0 ret:0
  [52.250613] perf_mmap user->locked_vm:0x38a pinned_vm:0x0 ret:0
  [52.250715] perf_mmap user->locked_vm:0x408 pinned_vm:0x2 ret:0
  [52.250834] perf_mmap user->locked_vm:0x408 pinned_vm:0x83 ret:0
  [52.250915] perf_mmap user->locked_vm:0x408 pinned_vm:0x103 ret:0
  [52.251061] perf_mmap user->locked_vm:0x408 pinned_vm:0x184 ret:0
  [52.251146] perf_mmap user->locked_vm:0x408 pinned_vm:0x204 ret:0
  [52.251299] perf_mmap user->locked_vm:0x408 pinned_vm:0x285 ret:0
  [52.251383] perf_mmap user->locked_vm:0x408 pinned_vm:0x305 ret:0
  [52.251544] perf_mmap user->locked_vm:0x408 pinned_vm:0x386 ret:0
  [52.251634] perf_mmap user->locked_vm:0x408 pinned_vm:0x406 ret:0
  [52.253018] perf_mmap user->locked_vm:0x408 pinned_vm:0x487 ret:0
  [52.253197] perf_mmap user->locked_vm:0x408 pinned_vm:0x508 ret:0
  [52.253374] perf_mmap user->locked_vm:0x408 pinned_vm:0x589 ret:0
  [52.253550] perf_mmap user->locked_vm:0x408 pinned_vm:0x60a ret:0
  [52.253726] perf_mmap user->locked_vm:0x408 pinned_vm:0x68b ret:0
  [52.253903] perf_mmap user->locked_vm:0x408 pinned_vm:0x70c ret:0
  [52.254084] perf_mmap user->locked_vm:0x408 pinned_vm:0x78d ret:0
  [52.254263] perf_mmap user->locked_vm:0x408 pinned_vm:0x80e ret:0

The value of user->locked_vm increases to a limit then the memory
is tracked by pinned_vm.

During deallocation the size is subtracted from pinned_vm until
it hits a limit. Then a larger value is subtracted from locked_vm
leading to a large number (because of type unsigned):

  [64.267797] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x78d
  [64.267826] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x70c
  [64.267848] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x68b
  [64.267869] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x60a
  [64.267891] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x589
  [64.267911] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x508
  [64.267933] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x487
  [64.267952] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x406
  [64.268883] perf_mmap_close mmap_user->locked_vm:0x307 pinned_vm:0x406
  [64.269117] perf_mmap_close mmap_user->locked_vm:0x206 pinned_vm:0x406
  [64.269433] perf_mmap_close mmap_user->locked_vm:0x105 pinned_vm:0x406
  [64.269536] perf_mmap_close mmap_user->locked_vm:0x4 pinned_vm:0x404
  [64.269797] perf_mmap_close mmap_user->locked_vm:0xffffffffffffff84 pinned_vm:0x303
  [64.270105] perf_mmap_close mmap_user->locked_vm:0xffffffffffffff04 pinned_vm:0x202
  [64.270374] perf_mmap_close mmap_user->locked_vm:0xfffffffffffffe84 pinned_vm:0x101
  [64.270628] perf_mmap_close mmap_user->locked_vm:0xfffffffffffffe04 pinned_vm:0x0

This value sticks for the user until system is rebooted, causing
follow-on system calls using locked_vm resource limit to fail.

Note: There is no issue using the normal trace buffer.

In fact the issue is in perf_mmap_close(). During allocation auxiliary
trace buffer memory is either traced as 'extra' and added to 'pinned_vm'
or trace as 'user_extra' and added to 'locked_vm'. This applies for
normal trace buffers and auxiliary trace buffer.

However in function perf_mmap_close() all auxiliary trace buffer is
subtraced from 'locked_vm' and never from 'pinned_vm'. This breaks the
ballance.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@kernel.org
Cc: gor@linux.ibm.com
Cc: hechaol@fb.com
Cc: heiko.carstens@de.ibm.com
Cc: linux-perf-users@vger.kernel.org
Cc: songliubraving@fb.com
Fixes: d44248a413 ("perf/core: Rework memory accounting in perf_mmap()")
Link: https://lkml.kernel.org/r/20191021083354.67868-1-tmricht@linux.ibm.com
[ Minor readability edits. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-21 11:31:24 +02:00
Rafael J. Wysocki 77751a466e PM: QoS: Introduce frequency QoS
Introduce frequency QoS, based on the "raw" low-level PM QoS, to
represent min and max frequency requests and aggregate constraints.

The min and max frequency requests are to be represented by
struct freq_qos_request objects and the aggregate constraints are to
be represented by struct freq_constraints objects.  The latter are
expected to be initialized with the help of freq_constraints_init().

The freq_qos_read_value() helper is defined to retrieve the aggregate
constraints values from a given struct freq_constraints object and
there are the freq_qos_add_request(), freq_qos_update_request() and
freq_qos_remove_request() helpers to manipulate the min and max
frequency requests.  It is assumed that the the helpers will not
run concurrently with each other for the same struct freq_qos_request
object, so if that may be the case, their uses must ensure proper
synchronization between them (e.g. through locking).

In addition, freq_qos_add_notifier() and freq_qos_remove_notifier()
are provided to add and remove notifiers that will trigger on aggregate
constraint changes to and from a given struct freq_constraints object,
respectively.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2019-10-21 02:05:21 +02:00
Linus Torvalds e2ab4ef83f Kbuild fixes for v5.4 (2nd)
- fix a bashism of setlocalversion
 
  - do not use the too new --sort option of tar
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Merge tag 'kbuild-fixes-v5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull more Kbuild fixes from Masahiro Yamada:

 - fix a bashism of setlocalversion

 - do not use the too new --sort option of tar

* tag 'kbuild-fixes-v5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kheaders: substituting --sort in archive creation
  scripts: setlocalversion: fix a bashism
  kbuild: update comment about KBUILD_ALLDIRS
2019-10-20 12:36:57 -04:00
Linus Torvalds 188768f3c0 Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull hrtimer fixlet from Thomas Gleixner:
 "A single commit annotating the lockcless access to timer->base with
  READ_ONCE() and adding the WRITE_ONCE() counterparts for completeness"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  hrtimer: Annotate lockless access to timer->base
2019-10-20 06:25:12 -04:00
Linus Torvalds 589f1222e0 Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull stop-machine fix from Thomas Gleixner:
 "A single fix, amending stop machine with WRITE/READ_ONCE() to address
  the fallout of KCSAN"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  stop_machine: Avoid potential race behaviour
2019-10-20 06:22:25 -04:00
Song Liu aa5de305c9 kernel/events/uprobes.c: only do FOLL_SPLIT_PMD for uprobe register
Attaching uprobe to text section in THP splits the PMD mapped page table
into PTE mapped entries.  On uprobe detach, we would like to regroup PMD
mapped page table entry to regain performance benefit of THP.

However, the regroup is broken For perf_event based trace_uprobe.  This
is because perf_event based trace_uprobe calls uprobe_unregister twice
on close: first in TRACE_REG_PERF_CLOSE, then in
TRACE_REG_PERF_UNREGISTER.  The second call will split the PMD mapped
page table entry, which is not the desired behavior.

Fix this by only use FOLL_SPLIT_PMD for uprobe register case.

Add a WARN() to confirm uprobe unregister never work on huge pages, and
abort the operation when this WARN() triggers.

Link: http://lkml.kernel.org/r/20191017164223.2762148-6-songliubraving@fb.com
Fixes: 5a52c9df62 ("uprobe: use FOLL_SPLIT_PMD instead of FOLL_SPLIT")
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-10-19 06:32:33 -04:00
Toke Høiland-Jørgensen 05679ca6fe xdp: Prevent overflow in devmap_hash cost calculation for 32-bit builds
Tetsuo pointed out that without an explicit cast, the cost calculation for
devmap_hash type maps could overflow on 32-bit builds. This adds the
missing cast.

Fixes: 6f9d451ab1 ("xdp: Add devmap_hash map type for looking up devices by hashed index")
Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20191017105702.2807093-1-toke@redhat.com
2019-10-18 16:18:42 -07:00
Zhengjun Xing 9fa8c9c647 tracing: Fix "gfp_t" format for synthetic events
In the format of synthetic events, the "gfp_t" is shown as "signed:1",
but in fact the "gfp_t" is "unsigned", should be shown as "signed:0".

The issue can be reproduced by the following commands:

echo 'memlatency u64 lat; unsigned int order; gfp_t gfp_flags; int migratetype' > /sys/kernel/debug/tracing/synthetic_events
cat  /sys/kernel/debug/tracing/events/synthetic/memlatency/format

name: memlatency
ID: 2233
format:
        field:unsigned short common_type;       offset:0;       size:2; signed:0;
        field:unsigned char common_flags;       offset:2;       size:1; signed:0;
        field:unsigned char common_preempt_count;       offset:3;       size:1; signed:0;
        field:int common_pid;   offset:4;       size:4; signed:1;

        field:u64 lat;  offset:8;       size:8; signed:0;
        field:unsigned int order;       offset:16;      size:4; signed:0;
        field:gfp_t gfp_flags;  offset:24;      size:4; signed:1;
        field:int migratetype;  offset:32;      size:4; signed:1;

print fmt: "lat=%llu, order=%u, gfp_flags=%x, migratetype=%d", REC->lat, REC->order, REC->gfp_flags, REC->migratetype

Link: http://lkml.kernel.org/r/20191018012034.6404-1-zhengjun.xing@linux.intel.com

Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Zhengjun Xing <zhengjun.xing@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-18 14:42:53 -04:00
Linus Torvalds e59b76ff67 Power management fixes for 5.4-rc4
- Fix possible NULL pointer dereference in the ACPI processor
    scaling initialization code introduced by a recent cpufreq
    update (Rafael Wysocki).
 
  - Fix possible deadlock due to suspending cpufreq too late during
    system shutdown (Rafael Wysocki).
 
  - Make the PCI device system resume code path be more consistent
    with its PM-runtime counterpart to fix an issue with missing
    delay on transitions from D3cold to D0 during system resume from
    suspend-to-idle on some systems (Rafael Wysocki).
 
  - Drop Dell XPS13 9360 from the LPS0 Idle _DSM blacklist to make it
    use suspend-to-idle by default (Mario Limonciello).
 
  - Fix build warning in the core system suspend support code (Ben
    Dooks).
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Merge tag 'pm-5.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management fixes from Rafael Wysocki:
 "These include a fix for a recent regression in the ACPI CPU
performance scaling code, a PCI device power management fix,
a system shutdown fix related to cpufreq, a removal of an ACPI
suspend-to-idle blacklist entry and a build warning fix.

Specifics:

   - Fix possible NULL pointer dereference in the ACPI processor scaling
     initialization code introduced by a recent cpufreq update (Rafael
     Wysocki).

   - Fix possible deadlock due to suspending cpufreq too late during
     system shutdown (Rafael Wysocki).

   - Make the PCI device system resume code path be more consistent with
     its PM-runtime counterpart to fix an issue with missing delay on
     transitions from D3cold to D0 during system resume from
     suspend-to-idle on some systems (Rafael Wysocki).

   - Drop Dell XPS13 9360 from the LPS0 Idle _DSM blacklist to make it
     use suspend-to-idle by default (Mario Limonciello).

   - Fix build warning in the core system suspend support code (Ben
     Dooks)"

* tag 'pm-5.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: processor: Avoid NULL pointer dereferences at init time
  PCI: PM: Fix pci_power_up()
  PM: sleep: include <linux/pm_runtime.h> for pm_wq
  cpufreq: Avoid cpufreq_suspend() deadlock on system shutdown
  ACPI: PM: Drop Dell XPS13 9360 from LPS0 Idle _DSM blacklist
2019-10-18 08:34:04 -07:00
Rafael J. Wysocki b23eb5c74e Merge branches 'pm-cpufreq' and 'pm-sleep'
* pm-cpufreq:
  ACPI: processor: Avoid NULL pointer dereferences at init time
  cpufreq: Avoid cpufreq_suspend() deadlock on system shutdown

* pm-sleep:
  PM: sleep: include <linux/pm_runtime.h> for pm_wq
  ACPI: PM: Drop Dell XPS13 9360 from LPS0 Idle _DSM blacklist
2019-10-18 10:27:55 +02:00
Mark Rutland b1fc583335 stop_machine: Avoid potential race behaviour
Both multi_cpu_stop() and set_state() access multi_stop_data::state
racily using plain accesses. These are subject to compiler
transformations which could break the intended behaviour of the code,
and this situation is detected by KCSAN on both arm64 and x86 (splats
below).

Improve matters by using READ_ONCE() and WRITE_ONCE() to ensure that the
compiler cannot elide, replay, or tear loads and stores.

In multi_cpu_stop() the two loads of multi_stop_data::state are expected to
be a consistent value, so snapshot the value into a temporary variable to
ensure this.

The state transitions are serialized by atomic manipulation of
multi_stop_data::num_threads, and other fields in multi_stop_data are not
modified while subject to concurrent reads.

KCSAN splat on arm64:

| BUG: KCSAN: data-race in multi_cpu_stop+0xa8/0x198 and set_state+0x80/0xb0
|
| write to 0xffff00001003bd00 of 4 bytes by task 24 on cpu 3:
|  set_state+0x80/0xb0
|  multi_cpu_stop+0x16c/0x198
|  cpu_stopper_thread+0x170/0x298
|  smpboot_thread_fn+0x40c/0x560
|  kthread+0x1a8/0x1b0
|  ret_from_fork+0x10/0x18
|
| read to 0xffff00001003bd00 of 4 bytes by task 14 on cpu 1:
|  multi_cpu_stop+0xa8/0x198
|  cpu_stopper_thread+0x170/0x298
|  smpboot_thread_fn+0x40c/0x560
|  kthread+0x1a8/0x1b0
|  ret_from_fork+0x10/0x18
|
| Reported by Kernel Concurrency Sanitizer on:
| CPU: 1 PID: 14 Comm: migration/1 Not tainted 5.3.0-00007-g67ab35a199f4-dirty #3
| Hardware name: linux,dummy-virt (DT)

KCSAN splat on x86:

| write to 0xffffb0bac0013e18 of 4 bytes by task 19 on cpu 2:
|  set_state kernel/stop_machine.c:170 [inline]
|  ack_state kernel/stop_machine.c:177 [inline]
|  multi_cpu_stop+0x1a4/0x220 kernel/stop_machine.c:227
|  cpu_stopper_thread+0x19e/0x280 kernel/stop_machine.c:516
|  smpboot_thread_fn+0x1a8/0x300 kernel/smpboot.c:165
|  kthread+0x1b5/0x200 kernel/kthread.c:255
|  ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:352
|
| read to 0xffffb0bac0013e18 of 4 bytes by task 44 on cpu 7:
|  multi_cpu_stop+0xb4/0x220 kernel/stop_machine.c:213
|  cpu_stopper_thread+0x19e/0x280 kernel/stop_machine.c:516
|  smpboot_thread_fn+0x1a8/0x300 kernel/smpboot.c:165
|  kthread+0x1b5/0x200 kernel/kthread.c:255
|  ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:352
|
| Reported by Kernel Concurrency Sanitizer on:
| CPU: 7 PID: 44 Comm: migration/7 Not tainted 5.3.0+ #1
| Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Marco Elver <elver@google.com>
Link: https://lkml.kernel.org/r/20191007104536.27276-1-mark.rutland@arm.com
2019-10-17 12:47:12 +02:00
Dmitry Goldin 700dea5a0b kheaders: substituting --sort in archive creation
The option --sort=ORDER was only introduced in tar 1.28 (2014), which
is rather new and might not be available in some setups.

This patch tries to replicate the previous behaviour as closely as
possible to fix the kheaders build for older environments. It does
not produce identical archives compared to the previous version due
to minor sorting differences but produces reproducible results itself
in my tests.

Reported-by: Andreas Schwab <schwab@suse.de>
Signed-off-by: Dmitry Goldin <dgoldin+lkml@protonmail.ch>
Tested-by: Andreas Schwab <schwab@suse.de>
Tested-by: Quentin Perret <qperret@google.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-10-17 09:08:19 +09:00
Ben Dooks bc88f85c6c kthread: make __kthread_queue_delayed_work static
The __kthread_queue_delayed_work is not exported so
make it static, to avoid the following sparse warning:

  kernel/kthread.c:869:6: warning: symbol '__kthread_queue_delayed_work' was not declared. Should it be static?

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-10-16 09:20:58 -07:00
Linus Torvalds 02755af0f3 Merge branch 'parisc-5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux
Pull parisc fixes from Helge Deller:

 - Fix a parisc-specific fallout of Christoph's
   dma_set_mask_and_coherent() patches (Sven)

 - Fix a vmap memory leak in ioremap()/ioremap() (Helge)

 - Some minor cleanups and documentation updates (Nick, Helge)

* 'parisc-5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Remove 32-bit DMA enforcement from sba_iommu
  parisc: Fix vmap memory leak in ioremap()/iounmap()
  parisc: prefer __section from compiler_attributes.h
  parisc: sysctl.c: Use CONFIG_PARISC instead of __hppa_ define
  MAINTAINERS: Add hp_sdc drivers to parisc arch
2019-10-15 09:37:01 -07:00
Helge Deller b67114db64 parisc: sysctl.c: Use CONFIG_PARISC instead of __hppa_ define
Signed-off-by: Helge Deller <deller@gmx.de>
2019-10-14 21:43:54 +02:00
Eric Dumazet ff229eee3d hrtimer: Annotate lockless access to timer->base
Followup to commit dd2261ed45 ("hrtimer: Protect lockless access
to timer->base")

lock_hrtimer_base() fetches timer->base without lock exclusion.

Compiler is allowed to read timer->base twice (even if considered dumb)
which could end up trying to lock migration_base and return
&migration_base.

  base = timer->base;
  if (likely(base != &migration_base)) {

       /* compiler reads timer->base again, and now (base == &migration_base)

       raw_spin_lock_irqsave(&base->cpu_base->lock, *flags);
       if (likely(base == timer->base))
            return base; /* == &migration_base ! */

Similarly the write sides must use WRITE_ONCE() to avoid store tearing.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191008173204.180879-1-edumazet@google.com
2019-10-14 15:51:49 +02:00
Linus Torvalds d4615e5a46 A few tracing fixes:
- Removed locked down from tracefs itself and moved it to the trace
    directory. Having the open functions there do the lockdown checks.
 
  - Fixed a few races with opening an instance file and the instance being
    deleted (Discovered during the locked down updates). Kept separate
    from the clean up code such that they can be backported to stable
    easier.
 
  - Cleaned up and consolidated the checks done when opening a trace
    file, as there were multiple checks that need to be done, and it
    did not make sense having them done in each open instance.
 
  - Fixed a regression in the record mcount code.
 
  - Small hw_lat detector tracer fixes.
 
  - A trace_pipe read fix due to not initializing trace_seq.
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Merge tag 'trace-v5.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "A few tracing fixes:

   - Remove lockdown from tracefs itself and moved it to the trace
     directory. Have the open functions there do the lockdown checks.

   - Fix a few races with opening an instance file and the instance
     being deleted (Discovered during the lockdown updates). Kept
     separate from the clean up code such that they can be backported to
     stable easier.

   - Clean up and consolidated the checks done when opening a trace
     file, as there were multiple checks that need to be done, and it
     did not make sense having them done in each open instance.

   - Fix a regression in the record mcount code.

   - Small hw_lat detector tracer fixes.

   - A trace_pipe read fix due to not initializing trace_seq"

* tag 'trace-v5.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Initialize iter->seq after zeroing in tracing_read_pipe()
  tracing/hwlat: Don't ignore outer-loop duration when calculating max_latency
  tracing/hwlat: Report total time spent in all NMIs during the sample
  recordmcount: Fix nop_mcount() function
  tracing: Do not create tracefs files if tracefs lockdown is in effect
  tracing: Add locked_down checks to the open calls of files created for tracefs
  tracing: Add tracing_check_open_get_tr()
  tracing: Have trace events system open call tracing_open_generic_tr()
  tracing: Get trace_array reference for available_tracers files
  ftrace: Get a reference counter for the trace_array on filter files
  tracefs: Revert ccbd54ff54 ("tracefs: Restrict tracefs when the kernel is locked down")
2019-10-13 14:47:10 -07:00
Petr Mladek d303de1fcf tracing: Initialize iter->seq after zeroing in tracing_read_pipe()
A customer reported the following softlockup:

[899688.160002] NMI watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [test.sh:16464]
[899688.160002] CPU: 0 PID: 16464 Comm: test.sh Not tainted 4.12.14-6.23-azure #1 SLE12-SP4
[899688.160002] RIP: 0010:up_write+0x1a/0x30
[899688.160002] Kernel panic - not syncing: softlockup: hung tasks
[899688.160002] RIP: 0010:up_write+0x1a/0x30
[899688.160002] RSP: 0018:ffffa86784d4fde8 EFLAGS: 00000257 ORIG_RAX: ffffffffffffff12
[899688.160002] RAX: ffffffff970fea00 RBX: 0000000000000001 RCX: 0000000000000000
[899688.160002] RDX: ffffffff00000001 RSI: 0000000000000080 RDI: ffffffff970fea00
[899688.160002] RBP: ffffffffffffffff R08: ffffffffffffffff R09: 0000000000000000
[899688.160002] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8b59014720d8
[899688.160002] R13: ffff8b59014720c0 R14: ffff8b5901471090 R15: ffff8b5901470000
[899688.160002]  tracing_read_pipe+0x336/0x3c0
[899688.160002]  __vfs_read+0x26/0x140
[899688.160002]  vfs_read+0x87/0x130
[899688.160002]  SyS_read+0x42/0x90
[899688.160002]  do_syscall_64+0x74/0x160

It caught the process in the middle of trace_access_unlock(). There is
no loop. So, it must be looping in the caller tracing_read_pipe()
via the "waitagain" label.

Crashdump analyze uncovered that iter->seq was completely zeroed
at this point, including iter->seq.seq.size. It means that
print_trace_line() was never able to print anything and
there was no forward progress.

The culprit seems to be in the code:

	/* reset all but tr, trace, and overruns */
	memset(&iter->seq, 0,
	       sizeof(struct trace_iterator) -
	       offsetof(struct trace_iterator, seq));

It was added by the commit 53d0aa7730 ("ftrace:
add logic to record overruns"). It was v2.6.27-rc1.
It was the time when iter->seq looked like:

     struct trace_seq {
	unsigned char		buffer[PAGE_SIZE];
	unsigned int		len;
     };

There was no "size" variable and zeroing was perfectly fine.

The solution is to reinitialize the structure after or without
zeroing.

Link: http://lkml.kernel.org/r/20191011142134.11997-1-pmladek@suse.com

Signed-off-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12 20:49:34 -04:00
Srivatsa S. Bhat (VMware) fc64e4ad80 tracing/hwlat: Don't ignore outer-loop duration when calculating max_latency
max_latency is intended to record the maximum ever observed hardware
latency, which may occur in either part of the loop (inner/outer). So
we need to also consider the outer-loop sample when updating
max_latency.

Link: http://lkml.kernel.org/r/157073345463.17189.18124025522664682811.stgit@srivatsa-ubuntu

Fixes: e7c15cd8a1 ("tracing: Added hardware latency tracer")
Cc: stable@vger.kernel.org
Signed-off-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12 20:49:33 -04:00
Srivatsa S. Bhat (VMware) 98dc19c114 tracing/hwlat: Report total time spent in all NMIs during the sample
nmi_total_ts is supposed to record the total time spent in *all* NMIs
that occur on the given CPU during the (active portion of the)
sampling window. However, the code seems to be overwriting this
variable for each NMI, thereby only recording the time spent in the
most recent NMI. Fix it by accumulating the duration instead.

Link: http://lkml.kernel.org/r/157073343544.17189.13911783866738671133.stgit@srivatsa-ubuntu

Fixes: 7b2c862501 ("tracing: Add NMI tracing in hwlat detector")
Cc: stable@vger.kernel.org
Signed-off-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12 20:49:33 -04:00
Steven Rostedt (VMware) 17911ff38a tracing: Add locked_down checks to the open calls of files created for tracefs
Added various checks on open tracefs calls to see if tracefs is in lockdown
mode, and if so, to return -EPERM.

Note, the event format files (which are basically standard on all machines)
as well as the enabled_functions file (which shows what is currently being
traced) are not lockde down. Perhaps they should be, but it seems counter
intuitive to lockdown information to help you know if the system has been
modified.

Link: http://lkml.kernel.org/r/CAHk-=wj7fGPKUspr579Cii-w_y60PtRaiDgKuxVtBAMK0VNNkA@mail.gmail.com

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12 20:48:06 -04:00
Steven Rostedt (VMware) 8530dec63e tracing: Add tracing_check_open_get_tr()
Currently, most files in the tracefs directory test if tracing_disabled is
set. If so, it should return -ENODEV. The tracing_disabled is called when
tracing is found to be broken. Originally it was done in case the ring
buffer was found to be corrupted, and we wanted to prevent reading it from
crashing the kernel. But it's also called if a tracing selftest fails on
boot. It's a one way switch. That is, once it is triggered, tracing is
disabled until reboot.

As most tracefs files can also be used by instances in the tracefs
directory, they need to be carefully done. Each instance has a trace_array
associated to it, and when the instance is removed, the trace_array is
freed. But if an instance is opened with a reference to the trace_array,
then it requires looking up the trace_array to get its ref counter (as there
could be a race with it being deleted and the open itself). Once it is
found, a reference is added to prevent the instance from being removed (and
the trace_array associated with it freed).

Combine the two checks (tracing_disabled and trace_array_get()) into a
single helper function. This will also make it easier to add lockdown to
tracefs later.

Link: http://lkml.kernel.org/r/20191011135458.7399da44@gandalf.local.home

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12 20:44:07 -04:00
Steven Rostedt (VMware) aa07d71f1b tracing: Have trace events system open call tracing_open_generic_tr()
Instead of having the trace events system open call open code the taking of
the trace_array descriptor (with trace_array_get()) and then calling
trace_open_generic(), have it use the tracing_open_generic_tr() that does
the combination of the two. This requires making tracing_open_generic_tr()
global.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12 20:43:00 -04:00
Steven Rostedt (VMware) 194c2c74f5 tracing: Get trace_array reference for available_tracers files
As instances may have different tracers available, we need to look at the
trace_array descriptor that shows the list of the available tracers for the
instance. But there's a race between opening the file and an admin
deleting the instance. The trace_array_get() needs to be called before
accessing the trace_array.

Cc: stable@vger.kernel.org
Fixes: 607e2ea167 ("tracing: Set up infrastructure to allow tracers for instances")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12 20:40:50 -04:00
Steven Rostedt (VMware) 9ef16693af ftrace: Get a reference counter for the trace_array on filter files
The ftrace set_ftrace_filter and set_ftrace_notrace files are specific for
an instance now. They need to take a reference to the instance otherwise
there could be a race between accessing the files and deleting the instance.

It wasn't until the :mod: caching where these file operations started
referencing the trace_array directly.

Cc: stable@vger.kernel.org
Fixes: 673feb9d76 ("ftrace: Add :mod: caching infrastructure to trace_array")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12 20:40:21 -04:00
Linus Torvalds 328fefadd9 Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
 "Two fixes: a guest-cputime accounting fix, and a cgroup bandwidth
  quota precision fix"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/vtime: Fix guest/system mis-accounting on task switch
  sched/fair: Scale bandwidth quota and period without losing quota/period ratio precision
2019-10-12 15:29:54 -07:00
Linus Torvalds 465a7e291f 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 a couple of updates for new Intel
  models (which are technically hw-enablement, but to users it's a fix
  to perf behavior on those new CPUs - hope this is fine), an AUX
  inheritance fix, event time-sharing fix, and a fix for lost non-perf
  NMI events on AMD systems"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits)
  perf/x86/cstate: Add Tiger Lake CPU support
  perf/x86/msr: Add Tiger Lake CPU support
  perf/x86/intel: Add Tiger Lake CPU support
  perf/x86/cstate: Update C-state counters for Ice Lake
  perf/x86/msr: Add new CPU model numbers for Ice Lake
  perf/x86/cstate: Add Comet Lake CPU support
  perf/x86/msr: Add Comet Lake CPU support
  perf/x86/intel: Add Comet Lake CPU support
  perf/x86/amd: Change/fix NMI latency mitigation to use a timestamp
  perf/core: Fix corner case in perf_rotate_context()
  perf/core: Rework memory accounting in perf_mmap()
  perf/core: Fix inheritance of aux_output groups
  perf annotate: Don't return -1 for error when doing BPF disassembly
  perf annotate: Return appropriate error code for allocation failures
  perf annotate: Fix arch specific ->init() failure errors
  perf annotate: Propagate the symbol__annotate() error return
  perf annotate: Fix the signedness of failure returns
  perf annotate: Propagate perf_env__arch() error
  perf evsel: Fall back to global 'perf_env' in perf_evsel__env()
  perf tools: Propagate get_cpuid() error
  ...
2019-10-12 15:15:17 -07:00
Linus Torvalds 297cbcccc2 for-linus-20191010
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Merge tag 'for-linus-20191010' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:

 - Fix wbt performance regression introduced with the blk-rq-qos
   refactoring (Harshad)

 - Fix io_uring fileset removal inadvertently killing the workqueue (me)

 - Fix io_uring typo in linked command nonblock submission (Pavel)

 - Remove spurious io_uring wakeups on request free (Pavel)

 - Fix null_blk zoned command error return (Keith)

 - Don't use freezable workqueues for backing_dev, also means we can
   revert a previous libata hack (Mika)

 - Fix nbd sysfs mutex dropped too soon at removal time (Xiubo)

* tag 'for-linus-20191010' of git://git.kernel.dk/linux-block:
  nbd: fix possible sysfs duplicate warning
  null_blk: Fix zoned command return code
  io_uring: only flush workqueues on fileset removal
  io_uring: remove wait loop spurious wakeups
  blk-wbt: fix performance regression in wbt scale_up/scale_down
  Revert "libata, freezer: avoid block device removal while system is frozen"
  bdi: Do not use freezable workqueue
  io_uring: fix reversed nonblock flag for link submission
2019-10-11 08:45:32 -07:00
Ben Dooks f49249d58a PM: sleep: include <linux/pm_runtime.h> for pm_wq
Include the <linux/runtime_pm.h> for the definition of
pm_wq to avoid the following warning:

kernel/power/main.c:890:25: warning: symbol 'pm_wq' was not declared. Should it be static?

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-10-10 11:11:56 +02:00
Song Liu 7fa343b7fd perf/core: Fix corner case in perf_rotate_context()
In perf_rotate_context(), when the first cpu flexible event fail to
schedule, cpu_rotate is 1, while cpu_event is NULL. Since cpu_event is
NULL, perf_rotate_context will _NOT_ call cpu_ctx_sched_out(), thus
cpuctx->ctx.is_active will have EVENT_FLEXIBLE set. Then, the next
perf_event_sched_in() will skip all cpu flexible events because of the
EVENT_FLEXIBLE bit.

In the next call of perf_rotate_context(), cpu_rotate stays 1, and
cpu_event stays NULL, so this process repeats. The end result is, flexible
events on this cpu will not be scheduled (until another event being added
to the cpuctx).

Here is an easy repro of this issue. On Intel CPUs, where ref-cycles
could only use one counter, run one pinned event for ref-cycles, one
flexible event for ref-cycles, and one flexible event for cycles. The
flexible ref-cycles is never scheduled, which is expected. However,
because of this issue, the cycles event is never scheduled either.

 $ perf stat -e ref-cycles:D,ref-cycles,cycles -C 5 -I 1000

           time             counts unit events
    1.000152973         15,412,480      ref-cycles:D
    1.000152973      <not counted>      ref-cycles     (0.00%)
    1.000152973      <not counted>      cycles         (0.00%)
    2.000486957         18,263,120      ref-cycles:D
    2.000486957      <not counted>      ref-cycles     (0.00%)
    2.000486957      <not counted>      cycles         (0.00%)

To fix this, when the flexible_active list is empty, try rotate the
first event in the flexible_groups. Also, rename ctx_first_active() to
ctx_event_to_rotate(), which is more accurate.

Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <kernel-team@fb.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 8d5bce0c37 ("perf/core: Optimize perf_rotate_context() event scheduling")
Link: https://lkml.kernel.org/r/20191008165949.920548-1-songliubraving@fb.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-09 12:44:13 +02:00
Song Liu d44248a413 perf/core: Rework memory accounting in perf_mmap()
perf_mmap() always increases user->locked_vm. As a result, "extra" could
grow bigger than "user_extra", which doesn't make sense. Here is an
example case:

(Note: Assume "user_lock_limit" is very small.)

  | # of perf_mmap calls |vma->vm_mm->pinned_vm|user->locked_vm|
  | 0                    | 0                   | 0             |
  | 1                    | user_extra          | user_extra    |
  | 2                    | 3 * user_extra      | 2 * user_extra|
  | 3                    | 6 * user_extra      | 3 * user_extra|
  | 4                    | 10 * user_extra     | 4 * user_extra|

Fix this by maintaining proper user_extra and extra.

Reviewed-By: Hechao Li <hechaol@fb.com>
Reported-by: Hechao Li <hechaol@fb.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <kernel-team@fb.com>
Cc: Jie Meng <jmeng@fb.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190904214618.3795672-1-songliubraving@fb.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-09 12:44:12 +02:00