commit 7b8474466e upstream.
On compat interfaces, the high order bits of nanoseconds should be zeroed
out. This is because the application code or the libc do not guarantee
zeroing of these. If used without zeroing, kernel might be at risk of using
timespec values incorrectly.
Originally it was handled correctly, but lost during is_compat_syscall()
cleanup. Revert the condition back to check CONFIG_64BIT.
Fixes: 98f76206b3 ("compat: Cleanup in_compat_syscall() callers")
Reported-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20191121000303.126523-1-dima@arista.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3ef240eaff upstream.
Oleg provided the following test case:
int main(void)
{
struct sched_param sp = {};
sp.sched_priority = 2;
assert(sched_setscheduler(0, SCHED_FIFO, &sp) == 0);
int lock = vfork();
if (!lock) {
sp.sched_priority = 1;
assert(sched_setscheduler(0, SCHED_FIFO, &sp) == 0);
_exit(0);
}
syscall(__NR_futex, &lock, FUTEX_LOCK_PI, 0,0,0);
return 0;
}
This creates an unkillable RT process spinning in futex_lock_pi() on a UP
machine or if the process is affine to a single CPU. The reason is:
parent child
set FIFO prio 2
vfork() -> set FIFO prio 1
implies wait_for_child() sched_setscheduler(...)
exit()
do_exit()
....
mm_release()
tsk->futex_state = FUTEX_STATE_EXITING;
exit_futex(); (NOOP in this case)
complete() --> wakes parent
sys_futex()
loop infinite because
tsk->futex_state == FUTEX_STATE_EXITING
The same problem can happen just by regular preemption as well:
task holds futex
...
do_exit()
tsk->futex_state = FUTEX_STATE_EXITING;
--> preemption (unrelated wakeup of some other higher prio task, e.g. timer)
switch_to(other_task)
return to user
sys_futex()
loop infinite as above
Just for the fun of it the futex exit cleanup could trigger the wakeup
itself before the task sets its futex state to DEAD.
To cure this, the handling of the exiting owner is changed so:
- A refcount is held on the task
- The task pointer is stored in a caller visible location
- The caller drops all locks (hash bucket, mmap_sem) and blocks
on task::futex_exit_mutex. When the mutex is acquired then
the exiting task has completed the cleanup and the state
is consistent and can be reevaluated.
This is not a pretty solution, but there is no choice other than returning
an error code to user space, which would break the state consistency
guarantee and open another can of problems including regressions.
For stable backports the preparatory commits ac31c7ff86 .. ba31c1a485
are required as well, but for anything older than 5.3.y the backports are
going to be provided when this hits mainline as the other dependencies for
those kernels are definitely not stable material.
Fixes: 778e9a9c3e ("pi-futex: fix exit races and locking problems")
Reported-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Stable Team <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20191106224557.041676471@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ac31c7ff86 upstream.
attach_to_pi_owner() returns -EAGAIN for various cases:
- Owner task is exiting
- Futex value has changed
The caller drops the held locks (hash bucket, mmap_sem) and retries the
operation. In case of the owner task exiting this can result in a live
lock.
As a preparatory step for seperating those cases, provide a distinct return
value (EBUSY) for the owner exiting case.
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191106224556.935606117@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3f186d9748 upstream.
The mutex will be used in subsequent changes to replace the busy looping of
a waiter when the futex owner is currently executing the exit cleanup to
prevent a potential live lock.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191106224556.845798895@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit af8cbda2cf upstream.
exec() attempts to handle potentially held futexes gracefully by running
the futex exit handling code like exit() does.
The current implementation has no protection against concurrent incoming
waiters. The reason is that the futex state cannot be set to
FUTEX_STATE_DEAD after the cleanup because the task struct is still active
and just about to execute the new binary.
While its arguably buggy when a task holds a futex over exec(), for
consistency sake the state handling can at least cover the actual futex
exit cleanup section. This provides state consistency protection accross
the cleanup. As the futex state of the task becomes FUTEX_STATE_OK after the
cleanup has been finished, this cannot prevent subsequent attempts to
attach to the task in case that the cleanup was not successfull in mopping
up all leftovers.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191106224556.753355618@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4a8e991b91 upstream.
Instead of having a smp_mb() and an empty lock/unlock of task::pi_lock move
the state setting into to the lock section.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191106224556.645603214@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 18f694385c upstream.
Instead of relying on PF_EXITING use an explicit state for the futex exit
and set it in the futex exit function. This moves the smp barrier and the
lock/unlock serialization into the futex code.
As with the DEAD state this is restricted to the exit path as exec
continues to use the same task struct.
This allows to simplify that logic in a next step.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191106224556.539409004@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f24f22435d upstream.
Setting task::futex_state in do_exit() is rather arbitrarily placed for no
reason. Move it into the futex code.
Note, this is only done for the exit cleanup as the exec cleanup cannot set
the state to FUTEX_STATE_DEAD because the task struct is still in active
use.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191106224556.439511191@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 150d71584b upstream.
To allow separate handling of the futex exit state in the futex exit code
for exit and exec, split futex_mm_release() into two functions and invoke
them from the corresponding exit/exec_mm_release() callsites.
Preparatory only, no functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191106224556.332094221@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4610ba7ad8 upstream.
mm_release() contains the futex exit handling. mm_release() is called from
do_exit()->exit_mm() and from exec()->exec_mm().
In the exit_mm() case PF_EXITING and the futex state is updated. In the
exec_mm() case these states are not touched.
As the futex exit code needs further protections against exit races, this
needs to be split into two functions.
Preparatory only, no functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191106224556.240518241@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3d4775df0a upstream.
The futex exit handling relies on PF_ flags. That's suboptimal as it
requires a smp_mb() and an ugly lock/unlock of the exiting tasks pi_lock in
the middle of do_exit() to enforce the observability of PF_EXITING in the
futex code.
Add a futex_state member to task_struct and convert the PF_EXITPIDONE logic
over to the new state. The PF_EXITING dependency will be cleaned up in a
later step.
This prepares for handling various futex exit issues later.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191106224556.149449274@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ba31c1a485 upstream.
The futex exit handling is #ifdeffed into mm_release() which is not pretty
to begin with. But upcoming changes to address futex exit races need to add
more functionality to this exit code.
Split it out into a function, move it into futex code and make the various
futex exit functions static.
Preparatory only and no functional change.
Folded build fix from Borislav.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191106224556.049705556@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ca16d5bee5 upstream.
Robust futexes utilize the robust_list mechanism to allow the kernel to
release futexes which are held when a task exits. The exit can be voluntary
or caused by a signal or fault. This prevents that waiters block forever.
The futex operations in user space store a pointer to the futex they are
either locking or unlocking in the op_pending member of the per task robust
list.
After a lock operation has succeeded the futex is queued in the robust list
linked list and the op_pending pointer is cleared.
After an unlock operation has succeeded the futex is removed from the
robust list linked list and the op_pending pointer is cleared.
The robust list exit code checks for the pending operation and any futex
which is queued in the linked list. It carefully checks whether the futex
value is the TID of the exiting task. If so, it sets the OWNER_DIED bit and
tries to wake up a potential waiter.
This is race free for the lock operation but unlock has two race scenarios
where waiters might not be woken up. These issues can be observed with
regular robust pthread mutexes. PI aware pthread mutexes are not affected.
(1) Unlocking task is killed after unlocking the futex value in user space
before being able to wake a waiter.
pthread_mutex_unlock()
|
V
atomic_exchange_rel (&mutex->__data.__lock, 0)
<------------------------killed
lll_futex_wake () |
|
|(__lock = 0)
|(enter kernel)
|
V
do_exit()
exit_mm()
mm_release()
exit_robust_list()
handle_futex_death()
|
|(__lock = 0)
|(uval = 0)
|
V
if ((uval & FUTEX_TID_MASK) != task_pid_vnr(curr))
return 0;
The sanity check which ensures that the user space futex is owned by
the exiting task prevents the wakeup of waiters which in consequence
block infinitely.
(2) Waiting task is killed after a wakeup and before it can acquire the
futex in user space.
OWNER WAITER
futex_wait()
pthread_mutex_unlock() |
| |
|(__lock = 0) |
| |
V |
futex_wake() ------------> wakeup()
|
|(return to userspace)
|(__lock = 0)
|
V
oldval = mutex->__data.__lock
<-----------------killed
atomic_compare_and_exchange_val_acq (&mutex->__data.__lock, |
id | assume_other_futex_waiters, 0) |
|
|
(enter kernel)|
|
V
do_exit()
|
|
V
handle_futex_death()
|
|(__lock = 0)
|(uval = 0)
|
V
if ((uval & FUTEX_TID_MASK) != task_pid_vnr(curr))
return 0;
The sanity check which ensures that the user space futex is owned
by the exiting task prevents the wakeup of waiters, which seems to
be correct as the exiting task does not own the futex value, but
the consequence is that other waiters wont be woken up and block
infinitely.
In both scenarios the following conditions are true:
- task->robust_list->list_op_pending != NULL
- user space futex value == 0
- Regular futex (not PI)
If these conditions are met then it is reasonably safe to wake up a
potential waiter in order to prevent the above problems.
As this might be a false positive it can cause spurious wakeups, but the
waiter side has to handle other types of unrelated wakeups, e.g. signals
gracefully anyway. So such a spurious wakeup will not affect the
correctness of these operations.
This workaround must not touch the user space futex value and cannot set
the OWNER_DIED bit because the lock value is 0, i.e. uncontended. Setting
OWNER_DIED in this case would result in inconsistent state and subsequently
in malfunction of the owner died handling in user space.
The rest of the user space state is still consistent as no other task can
observe the list_op_pending entry in the exiting tasks robust list.
The eventually woken up waiter will observe the uncontended lock value and
take it over.
[ tglx: Massaged changelog and comment. Made the return explicit and not
depend on the subsequent check and added constants to hand into
handle_futex_death() instead of plain numbers. Fixed a few coding
style issues. ]
Fixes: 0771dfefc9 ("[PATCH] lightweight robust futexes: core")
Signed-off-by: Yang Tao <yang.tao172@zte.com.cn>
Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1573010582-35297-1-git-send-email-wang.yi59@zte.com.cn
Link: https://lkml.kernel.org/r/20191106224555.943191378@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull networking fixes from David Miller:
1) Validate tunnel options length in act_tunnel_key, from Xin Long.
2) Fix DMA sync bug in gve driver, from Adi Suresh.
3) TSO kills performance on some r8169 chips due to HW issues, disable
by default in that case, from Corinna Vinschen.
4) Fix clock disable mismatch in fec driver, from Chubong Yuan.
5) Fix interrupt status bits define in hns3 driver, from Huazhong Tan.
6) Fix workqueue deadlocks in qeth driver, from Julian Wiedmann.
7) Don't napi_disable() twice in r8152 driver, from Hayes Wang.
8) Fix SKB extension memory leak, from Florian Westphal.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (54 commits)
r8152: avoid to call napi_disable twice
MAINTAINERS: Add myself as maintainer of virtio-vsock
udp: drop skb extensions before marking skb stateless
net: rtnetlink: prevent underflows in do_setvfinfo()
can: m_can_platform: remove unnecessary m_can_class_resume() call
can: m_can_platform: set net_device structure as driver data
hv_netvsc: Fix send_table offset in case of a host bug
hv_netvsc: Fix offset usage in netvsc_send_table()
net-ipv6: IPV6_TRANSPARENT - check NET_RAW prior to NET_ADMIN
sfc: Only cancel the PPS workqueue if it exists
nfc: port100: handle command failure cleanly
net-sysfs: fix netdev_queue_add_kobject() breakage
r8152: Re-order napi_disable in rtl8152_close
net: qca_spi: Move reset_count to struct qcaspi
net: qca_spi: fix receive buffer size check
net/ibmvnic: Ignore H_FUNCTION return from H_EOI to tolerate XIVE mode
Revert "net/ibmvnic: Fix EOI when running in XIVE mode"
net/mlxfw: Verify FSM error code translation doesn't exceed array size
net/mlx5: Update the list of the PCI supported devices
net/mlx5: Fix auto group size calculation
...
Fix problems with switching cpufreq drivers on some x86 systems with
ACPI (and with changing the operation modes of the intel_pstate driver
on those systems) introduced by recent changes related to the
management of frequency limits in cpufreq.
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Merge tag 'pm-5.4-final' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management regression fix from Rafael Wysocki:
"Fix problems with switching cpufreq drivers on some x86 systems with
ACPI (and with changing the operation modes of the intel_pstate driver
on those systems) introduced by recent changes related to the
management of frequency limits in cpufreq"
* tag 'pm-5.4-final' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM: QoS: Invalidate frequency QoS requests after removal
pidfd_poll() is defined as returning 'unsigned int' but the
.poll method is declared as returning '__poll_t', a bitwise type.
Fix this by using the proper return type and using the EPOLL
constants instead of the POLL ones, as required for __poll_t.
Fixes: b53b0b9d9a ("pidfd: add polling support")
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: stable@vger.kernel.org # 5.3
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com>
Link: https://lore.kernel.org/r/20191120003320.31138-1-luc.vanoostenryck@gmail.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Switching cpufreq drivers (or switching operation modes of the
intel_pstate driver from "active" to "passive" and vice versa)
does not work on some x86 systems with ACPI after commit
3000ce3c52 ("cpufreq: Use per-policy frequency QoS"), because
the ACPI _PPC and thermal code uses the same frequency QoS request
object for a given CPU every time a cpufreq driver is registered
and freq_qos_remove_request() does not invalidate the request after
removing it from its QoS list, so freq_qos_add_request() complains
and fails when that request is passed to it again.
Fix the issue by modifying freq_qos_remove_request() to clear the qos
and type fields of the frequency request pointed to by its argument
after removing it from its QoS list so as to invalidate it.
Fixes: 3000ce3c52 ("cpufreq: Use per-policy frequency QoS")
Reported-and-tested-by: Doug Smythies <dsmythies@telus.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Daniel Borkmann says:
====================
pull-request: bpf 2019-11-15
The following pull-request contains BPF updates for your *net* tree.
We've added 1 non-merge commits during the last 9 day(s) which contain
a total of 1 file changed, 3 insertions(+), 1 deletion(-).
The main changes are:
1) Fix a missing unlock of bpf_devs_lock in bpf_offload_dev_create()'s
error path, from Dan.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull perf fixes from Ingo Molnar:
"Misc fixes: a handful of AUX event handling related fixes, a Sparse
fix and two ABI fixes"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Fix missing static inline on perf_cgroup_switch()
perf/core: Consistently fail fork on allocation failures
perf/aux: Disallow aux_output for kernel events
perf/core: Reattach a misplaced comment
perf/aux: Fix the aux_output group inheritance fix
perf/core: Disallow uncore-cgroup events
Pull misc vfs fixes from Al Viro:
"Assorted fixes all over the place; some of that is -stable fodder,
some regressions from the last window"
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
ecryptfs_lookup_interpose(): lower_dentry->d_parent is not stable either
ecryptfs_lookup_interpose(): lower_dentry->d_inode is not stable
ecryptfs: fix unlink and rmdir in face of underlying fs modifications
audit_get_nd(): don't unlock parent too early
exportfs_decode_fh(): negative pinned may become positive without the parent locked
cgroup: don't put ERR_PTR() into fc->root
autofs: fix a leak in autofs_expire_indirect()
aio: Fix io_pgetevents() struct __compat_aio_sigset layout
fs/namespace.c: fix use-after-free of mount in mnt_warn_timestamp_expiry()
uclamp_update_active() should perform the update when
p->uclamp[clamp_id].active is true. But when the logic was inverted in
[1], the if condition wasn't inverted correctly too.
[1] https://lore.kernel.org/lkml/20190902073836.GO2369@hirez.programming.kicks-ass.net/
Reported-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Ben Segall <bsegall@google.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Patrick Bellasi <patrick.bellasi@matbug.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: babbe170e0 ("sched/uclamp: Update CPU's refcount on TG's clamp changes")
Link: https://lkml.kernel.org/r/20191114211052.15116-1-qais.yousef@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
It looks like a "static inline" has been missed in front
of the empty definition of perf_cgroup_switch() under
certain configurations.
Fixes the following sparse warning:
kernel/events/core.c:1035:1: warning: symbol 'perf_cgroup_switch' was not declared. Should it be static?
Signed-off-by: Ben Dooks (Codethink) <ben.dooks@codethink.co.uk>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
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>
Link: https://lkml.kernel.org/r/20191106132527.19977-1-ben.dooks@codethink.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commit:
313ccb9615 ("perf: Allocate context task_ctx_data for child event")
makes the inherit path skip over the current event in case of task_ctx_data
allocation failure. This, however, is inconsistent with allocation failures
in perf_event_alloc(), which would abort the fork.
Correct this by returning an error code on task_ctx_data allocation
failure and failing the fork in that case.
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: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
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>
Link: https://lkml.kernel.org/r/20191105075702.60319-1-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commit
ab43762ef0 ("perf: Allow normal events to output AUX data")
added 'aux_output' bit to the attribute structure, which relies on AUX
events and grouping, neither of which is supported for the kernel events.
This notwithstanding, attempts have been made to use it in the kernel
code, suggesting the necessity of an explicit hard -EINVAL.
Fix this by rejecting attributes with aux_output set for kernel events.
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: David Ahern <dsahern@gmail.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>
Link: https://lkml.kernel.org/r/20191030134731.5437-3-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
A comment is in a wrong place in perf_event_create_kernel_counter().
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: David Ahern <dsahern@gmail.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>
Link: https://lkml.kernel.org/r/20191030134731.5437-2-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
While discussing uncore event scheduling, I noticed we do not in fact
seem to dis-allow making uncore-cgroup events. Such events make no
sense what so ever because the cgroup is a CPU local state where
uncore counts across a number of CPUs.
Disallow them.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.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>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
While seemingly harmless, __sched_fork() does hrtimer_init(), which,
when DEBUG_OBJETS, can end up doing allocations.
This then results in the following lock order:
rq->lock
zone->lock.rlock
batched_entropy_u64.lock
Which in turn causes deadlocks when we do wakeups while holding that
batched_entropy lock -- as the random code does.
Solve this by moving __sched_fork() out from under rq->lock. This is
safe because nothing there relies on rq->lock, as also evident from the
other __sched_fork() callsite.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Qian Cai <cai@lca.pw>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akpm@linux-foundation.org
Cc: bigeasy@linutronix.de
Cc: cl@linux.com
Cc: keescook@chromium.org
Cc: penberg@kernel.org
Cc: rientjes@google.com
Cc: thgarnie@google.com
Cc: tytso@mit.edu
Cc: will@kernel.org
Fixes: b7d5dc2107 ("random: add a spinlock_t to struct batched_entropy")
Link: https://lkml.kernel.org/r/20191001091837.GK4536@hirez.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull x86 TSX Async Abort and iTLB Multihit mitigations from Thomas Gleixner:
"The performance deterioration departement is not proud at all of
presenting the seventh installment of speculation mitigations and
hardware misfeature workarounds:
1) TSX Async Abort (TAA) - 'The Annoying Affair'
TAA is a hardware vulnerability that allows unprivileged
speculative access to data which is available in various CPU
internal buffers by using asynchronous aborts within an Intel TSX
transactional region.
The mitigation depends on a microcode update providing a new MSR
which allows to disable TSX in the CPU. CPUs which have no
microcode update can be mitigated by disabling TSX in the BIOS if
the BIOS provides a tunable.
Newer CPUs will have a bit set which indicates that the CPU is not
vulnerable, but the MSR to disable TSX will be available
nevertheless as it is an architected MSR. That means the kernel
provides the ability to disable TSX on the kernel command line,
which is useful as TSX is a truly useful mechanism to accelerate
side channel attacks of all sorts.
2) iITLB Multihit (NX) - 'No eXcuses'
iTLB Multihit is an erratum where some Intel processors may incur
a machine check error, possibly resulting in an unrecoverable CPU
lockup, when an instruction fetch hits multiple entries in the
instruction TLB. This can occur when the page size is changed
along with either the physical address or cache type. A malicious
guest running on a virtualized system can exploit this erratum to
perform a denial of service attack.
The workaround is that KVM marks huge pages in the extended page
tables as not executable (NX). If the guest attempts to execute in
such a page, the page is broken down into 4k pages which are
marked executable. The workaround comes with a mechanism to
recover these shattered huge pages over time.
Both issues come with full documentation in the hardware
vulnerabilities section of the Linux kernel user's and administrator's
guide.
Thanks to all patch authors and reviewers who had the extraordinary
priviledge to be exposed to this nuisance.
Special thanks to Borislav Petkov for polishing the final TAA patch
set and to Paolo Bonzini for shepherding the KVM iTLB workarounds and
providing also the backports to stable kernels for those!"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/speculation/taa: Fix printing of TAA_MSG_SMT on IBRS_ALL CPUs
Documentation: Add ITLB_MULTIHIT documentation
kvm: x86: mmu: Recovery of shattered NX large pages
kvm: Add helper function for creating VM worker threads
kvm: mmu: ITLB_MULTIHIT mitigation
cpu/speculation: Uninline and export CPU mitigations helpers
x86/cpu: Add Tremont to the cpu vulnerability whitelist
x86/bugs: Add ITLB_MULTIHIT bug infrastructure
x86/tsx: Add config options to set tsx=on|off|auto
x86/speculation/taa: Add documentation for TSX Async Abort
x86/tsx: Add "auto" option to the tsx= cmdline parameter
kvm/x86: Export MDS_NO=0 to guests when TSX is enabled
x86/speculation/taa: Add sysfs reporting for TSX Async Abort
x86/speculation/taa: Add mitigation for TSX Async Abort
x86/cpu: Add a "tsx=" cmdline option with TSX disabled by default
x86/cpu: Add a helper function x86_read_arch_cap_msr()
x86/msr: Add the IA32_TSX_CTRL MSR
A cast to 'time_t' was accidentally left in place during the
conversion of __do_adjtimex() to 64-bit timestamps, so the
resulting value is incorrectly truncated.
Remove the cast so the 64-bit time gets propagated correctly.
Fixes: ead25417f8 ("timex: use __kernel_timex internally")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20191108203435.112759-2-arnd@arndb.de
Pull cgroup fix from Tejun Heo:
"There's an inadvertent preemption point in ptrace_stop() which was
reliably triggering for a test scenario significantly slowing it down.
This contains Oleg's fix to remove the unwanted preemption point"
* 'for-5.4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup: freezer: call cgroup_enter_frozen() with preemption disabled in ptrace_stop()
Pull timer fixes from Thomas Gleixner:
"A small set of fixes for timekeepoing and clocksource drivers:
- VDSO data was updated conditional on the availability of a VDSO
capable clocksource. This causes the VDSO functions which do not
depend on a VDSO capable clocksource to operate on stale data.
Always update unconditionally.
- Prevent a double free in the mediatek driver
- Use the proper helper in the sh_mtu2 driver so it won't attempt to
initialize non-existing interrupts"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
timekeeping/vsyscall: Update VDSO data unconditionally
clocksource/drivers/sh_mtu2: Do not loop using platform_get_irq_by_name()
clocksource/drivers/mediatek: Fix error handling
Pull scheduler fixes from Thomas Gleixner:
"Two fixes for scheduler regressions:
- Plug a subtle race condition which was introduced with the rework
of the next task selection functionality. The change of task
properties became unprotected which can be observed inconsistently
causing state corruption.
- A trivial compile fix for CONFIG_CGROUPS=n"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched: Fix pick_next_task() vs 'change' pattern race
sched/core: Fix compilation error when cgroup not selected
Pull irq fixlet from Thomas Gleixner:
"A trivial fix for a kernel doc regression where an argument change was
not reflected in the documentation"
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irq/irqdomain: Update __irq_domain_alloc_fwnode() function documentation
Pull stacktrace fix from Thomas Gleixner:
"A small fix for a stacktrace regression.
Saving a stacktrace for a foreign task skipped an extra entry which
makes e.g. the output of /proc/$PID/stack incomplete"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
stacktrace: Don't skip first entry on noncurrent tasks
if the child has been negative and just went positive
under us, we want coherent d_is_positive() and ->d_inode.
Don't unlock the parent until we'd done that work...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
the caller of ->get_tree() expects NULL left there on error...
Reported-by: Thibaut Sautereau <thibaut@sautereau.fr>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull networking fixes from David Miller:
1) BPF sample build fixes from Björn Töpel
2) Fix powerpc bpf tail call implementation, from Eric Dumazet.
3) DCCP leaks jiffies on the wire, fix also from Eric Dumazet.
4) Fix crash in ebtables when using dnat target, from Florian Westphal.
5) Fix port disable handling whne removing bcm_sf2 driver, from Florian
Fainelli.
6) Fix kTLS sk_msg trim on fallback to copy mode, from Jakub Kicinski.
7) Various KCSAN fixes all over the networking, from Eric Dumazet.
8) Memory leaks in mlx5 driver, from Alex Vesker.
9) SMC interface refcounting fix, from Ursula Braun.
10) TSO descriptor handling fixes in stmmac driver, from Jose Abreu.
11) Add a TX lock to synchonize the kTLS TX path properly with crypto
operations. From Jakub Kicinski.
12) Sock refcount during shutdown fix in vsock/virtio code, from Stefano
Garzarella.
13) Infinite loop in Intel ice driver, from Colin Ian King.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (108 commits)
ixgbe: need_wakeup flag might not be set for Tx
i40e: need_wakeup flag might not be set for Tx
igb/igc: use ktime accessors for skb->tstamp
i40e: Fix for ethtool -m issue on X722 NIC
iavf: initialize ITRN registers with correct values
ice: fix potential infinite loop because loop counter being too small
qede: fix NULL pointer deref in __qede_remove()
net: fix data-race in neigh_event_send()
vsock/virtio: fix sock refcnt holding during the shutdown
net: ethernet: octeon_mgmt: Account for second possible VLAN header
mac80211: fix station inactive_time shortly after boot
net/fq_impl: Switch to kvmalloc() for memory allocation
mac80211: fix ieee80211_txq_setup_flows() failure path
ipv4: Fix table id reference in fib_sync_down_addr
ipv6: fixes rt6_probe() and fib6_nh->last_probe init
net: hns: Fix the stray netpoll locks causing deadlock in NAPI path
net: usb: qmi_wwan: add support for DW5821e with eSIM support
CDC-NCM: handle incomplete transfer of MTU
nfc: netlink: fix double device reference drop
NFC: st21nfca: fix double free
...
Commit 67692435c4 ("sched: Rework pick_next_task() slow-path")
inadvertly introduced a race because it changed a previously
unexplored dependency between dropping the rq->lock and
sched_class::put_prev_task().
The comments about dropping rq->lock, in for example
newidle_balance(), only mentions the task being current and ->on_cpu
being set. But when we look at the 'change' pattern (in for example
sched_setnuma()):
queued = task_on_rq_queued(p); /* p->on_rq == TASK_ON_RQ_QUEUED */
running = task_current(rq, p); /* rq->curr == p */
if (queued)
dequeue_task(...);
if (running)
put_prev_task(...);
/* change task properties */
if (queued)
enqueue_task(...);
if (running)
set_next_task(...);
It becomes obvious that if we do this after put_prev_task() has
already been called on @p, things go sideways. This is exactly what
the commit in question allows to happen when it does:
prev->sched_class->put_prev_task(rq, prev, rf);
if (!rq->nr_running)
newidle_balance(rq, rf);
The newidle_balance() call will drop rq->lock after we've called
put_prev_task() and that allows the above 'change' pattern to
interleave and mess up the state.
Furthermore, it turns out we lost the RT-pull when we put the last DL
task.
Fix both problems by extracting the balancing from put_prev_task() and
doing a multi-class balance() pass before put_prev_task().
Fixes: 67692435c4 ("sched: Rework pick_next_task() slow-path")
Reported-by: Quentin Perret <qperret@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Quentin Perret <qperret@google.com>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
When cgroup is disabled the following compilation error was hit
kernel/sched/core.c: In function ‘uclamp_update_active_tasks’:
kernel/sched/core.c:1081:23: error: storage size of ‘it’ isn’t known
struct css_task_iter it;
^~
kernel/sched/core.c:1084:2: error: implicit declaration of function ‘css_task_iter_start’; did you mean ‘__sg_page_iter_start’? [-Werror=implicit-function-declaration]
css_task_iter_start(css, 0, &it);
^~~~~~~~~~~~~~~~~~~
__sg_page_iter_start
kernel/sched/core.c:1085:14: error: implicit declaration of function ‘css_task_iter_next’; did you mean ‘__sg_page_iter_next’? [-Werror=implicit-function-declaration]
while ((p = css_task_iter_next(&it))) {
^~~~~~~~~~~~~~~~~~
__sg_page_iter_next
kernel/sched/core.c:1091:2: error: implicit declaration of function ‘css_task_iter_end’; did you mean ‘get_task_cred’? [-Werror=implicit-function-declaration]
css_task_iter_end(&it);
^~~~~~~~~~~~~~~~~
get_task_cred
kernel/sched/core.c:1081:23: warning: unused variable ‘it’ [-Wunused-variable]
struct css_task_iter it;
^~
cc1: some warnings being treated as errors
make[2]: *** [kernel/sched/core.o] Error 1
Fix by protetion uclamp_update_active_tasks() with
CONFIG_UCLAMP_TASK_GROUP
Fixes: babbe170e0 ("sched/uclamp: Update CPU's refcount on TG's clamp changes")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Patrick Bellasi <patrick.bellasi@matbug.net>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Ben Segall <bsegall@google.com>
Link: https://lkml.kernel.org/r/20191105112212.596-1-qais.yousef@arm.com
We need to drop the bpf_devs_lock on error before returning.
Fixes: 9fd7c55591 ("bpf: offload: aggregate offloads per-device")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Link: https://lore.kernel.org/bpf/20191104091536.GB31509@mwanda
Daniel Borkmann says:
====================
pull-request: bpf 2019-11-02
The following pull-request contains BPF updates for your *net* tree.
We've added 6 non-merge commits during the last 6 day(s) which contain
a total of 8 files changed, 35 insertions(+), 9 deletions(-).
The main changes are:
1) Fix ppc BPF JIT's tail call implementation by performing a second pass
to gather a stable JIT context before opcode emission, from Eric Dumazet.
2) Fix build of BPF samples sys_perf_event_open() usage to compiled out
unavailable test_attr__{enabled,open} checks. Also fix potential overflows
in bpf_map_{area_alloc,charge_init} on 32 bit archs, from Björn Töpel.
3) Fix narrow loads of bpf_sysctl context fields with offset > 0 on big endian
archs like s390x and also improve the test coverage, from Ilya Leoshkevich.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
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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
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
A recent commit changed a parameter of __irq_domain_alloc_fwnode(), but
did not update the documentation comment. Fix it up.
Fixes: b977fcf477 ("irqdomain/debugfs: Use PAs to generate fwnode names")
Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/1571476047-29463-1-git-send-email-wang.yi59@zte.com.cn
The update of the VDSO data is depending on __arch_use_vsyscall() returning
True. This is a leftover from the attempt to map the features of various
architectures 1:1 into generic code.
The usage of __arch_use_vsyscall() in the actual vsyscall implementations
got dropped and replaced by the requirement for the architecture code to
return U64_MAX if the global clocksource is not usable in the VDSO.
But the __arch_use_vsyscall() check in the update code stayed which causes
the VDSO data to be stale or invalid when an architecture actually
implements that function and returns False when the current clocksource is
not usable in the VDSO.
As a consequence the VDSO implementations of clock_getres(), time(),
clock_gettime(CLOCK_.*_COARSE) operate on invalid data and return bogus
information.
Remove the __arch_use_vsyscall() check from the VDSO update function and
update the VDSO data unconditionally.
[ tglx: Massaged changelog and removed the now useless implementations in
asm-generic/ARM64/MIPS ]
Fixes: 44f57d788e ("timekeeping: Provide a generic update_vsyscall() implementation")
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1571887709-11447-1-git-send-email-chenhc@lemote.com
When doing cat /proc/<PID>/stack, the output is missing the first entry.
When the current code walks the stack starting in stack_trace_save_tsk,
it skips all scheduler functions (that's OK) plus one more function. But
this one function should be skipped only for the 'current' task as it is
stack_trace_save_tsk proper.
The original code (before the common infrastructure) skipped one
function only for the 'current' task -- see save_stack_trace_tsk before
3599fe12a1. So do so also in the new infrastructure now.
Fixes: 214d8ca6ee ("stacktrace: Provide common infrastructure")
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Michal Suchanek <msuchanek@suse.de>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20191030072545.19462-1-jslaby@suse.cz
Dmitry Safonov