Граф коммитов

996159 Коммитов

Автор SHA1 Сообщение Дата
Steven Rostedt (VMware) ee666a1855 tracing: Skip selftests if tracing is disabled
If tracing is disabled for some reason (traceoff_on_warning, command line,
etc), the ftrace selftests are guaranteed to fail, as their results are
defined by trace data in the ring buffers. If the ring buffers are turned
off, the tests will fail, due to lack of data.

Because tracing being disabled is for a specific reason (warning, user
decided to, etc), it does not make sense to enable tracing to run the self
tests, as the test output may corrupt the reason for the tracing to be
disabled.

Instead, simply skip the self tests and report that they are being skipped
due to tracing being disabled.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-03-04 09:51:25 -05:00
Vamshi K Sthambamkadi f40fc799af tracing: Fix memory leak in __create_synth_event()
kmemleak report:
unreferenced object 0xc5a6f708 (size 8):
  comm "ftracetest", pid 1209, jiffies 4294911500 (age 6.816s)
  hex dump (first 8 bytes):
    00 c1 3d 60 14 83 1f 8a                          ..=`....
  backtrace:
    [<f0aa4ac4>] __kmalloc_track_caller+0x2a6/0x460
    [<7d3d60a6>] kstrndup+0x37/0x70
    [<45a0e739>] argv_split+0x1c/0x120
    [<c17982f8>] __create_synth_event+0x192/0xb00
    [<0708b8a3>] create_synth_event+0xbb/0x150
    [<3d1941e1>] create_dyn_event+0x5c/0xb0
    [<5cf8b9e3>] trace_parse_run_command+0xa7/0x140
    [<04deb2ef>] dyn_event_write+0x10/0x20
    [<8779ac95>] vfs_write+0xa9/0x3c0
    [<ed93722a>] ksys_write+0x89/0xc0
    [<b9ca0507>] __ia32_sys_write+0x15/0x20
    [<7ce02d85>] __do_fast_syscall_32+0x45/0x80
    [<cb0ecb35>] do_fast_syscall_32+0x29/0x60
    [<2467454a>] do_SYSENTER_32+0x15/0x20
    [<9beaa61d>] entry_SYSENTER_32+0xa9/0xfc
unreferenced object 0xc5a6f078 (size 8):
  comm "ftracetest", pid 1209, jiffies 4294911500 (age 6.816s)
  hex dump (first 8 bytes):
    08 f7 a6 c5 00 00 00 00                          ........
  backtrace:
    [<bbac096a>] __kmalloc+0x2b6/0x470
    [<aa2624b4>] argv_split+0x82/0x120
    [<c17982f8>] __create_synth_event+0x192/0xb00
    [<0708b8a3>] create_synth_event+0xbb/0x150
    [<3d1941e1>] create_dyn_event+0x5c/0xb0
    [<5cf8b9e3>] trace_parse_run_command+0xa7/0x140
    [<04deb2ef>] dyn_event_write+0x10/0x20
    [<8779ac95>] vfs_write+0xa9/0x3c0
    [<ed93722a>] ksys_write+0x89/0xc0
    [<b9ca0507>] __ia32_sys_write+0x15/0x20
    [<7ce02d85>] __do_fast_syscall_32+0x45/0x80
    [<cb0ecb35>] do_fast_syscall_32+0x29/0x60
    [<2467454a>] do_SYSENTER_32+0x15/0x20
    [<9beaa61d>] entry_SYSENTER_32+0xa9/0xfc

In __create_synth_event(), while iterating field/type arguments, the
argv_split() will return array of atleast 2 elements even when zero
arguments(argc=0) are passed. for e.g. when there is double delimiter
or string ends with delimiter

To fix call argv_free() even when argc=0.

Link: https://lkml.kernel.org/r/20210304094521.GA1826@cosmos

Signed-off-by: Vamshi K Sthambamkadi <vamshi.k.sthambamkadi@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-03-04 09:45:57 -05:00
Steven Rostedt (VMware) 6549de1fe3 ring-buffer: Add a little more information and a WARN when time stamp going backwards is detected
When the CONFIG_RING_BUFFER_VALIDATE_TIME_DELTAS is enabled, and the time
stamps are detected as not being valid, it reports information about the
write stamp, but does not show the before_stamp which is still useful
information. Also, it should give a warning once, such that tests detect
this happening.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-03-04 09:45:17 -05:00
Steven Rostedt (VMware) 6f6be606e7 ring-buffer: Force before_stamp and write_stamp to be different on discard
Part of the logic of the new time stamp code depends on the before_stamp and
the write_stamp to be different if the write_stamp does not match the last
event on the buffer, as it will be used to calculate the delta of the next
event written on the buffer.

The discard logic depends on this, as the next event to come in needs to
inject a full timestamp as it can not rely on the last event timestamp in
the buffer because it is unknown due to events after it being discarded. But
by changing the write_stamp back to the time before it, it forces the next
event to use a full time stamp, instead of relying on it.

The issue came when a full time stamp was used for the event, and
rb_time_delta() returns zero in that case. The update to the write_stamp
(which subtracts delta) made it not change. Then when the event is removed
from the buffer, because the before_stamp and write_stamp still match, the
next event written would calculate its delta from the write_stamp, but that
would be wrong as the write_stamp is of the time of the event that was
discarded.

In the case that the delta change being made to write_stamp is zero, set the
before_stamp to zero as well, and this will force the next event to inject a
full timestamp and not use the current write_stamp.

Cc: stable@vger.kernel.org
Fixes: a389d86f7f ("ring-buffer: Have nested events still record running time stamp")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-03-04 09:45:17 -05:00
Rolf Eike Beer 69268094a1 tracing: Fix help text of TRACEPOINT_BENCHMARK in Kconfig
It's "cond_resched()" not "cond_sched()".

Link: https://lkml.kernel.org/r/1863065.aFVDpXsuPd@devpool47

Signed-off-by: Rolf Eike Beer <eb@emlix.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-03-04 09:45:17 -05:00
Yordan Karadzhov (VMware) 70d443d846 tracing: Remove duplicate declaration from trace.h
A declaration of function "int trace_empty(struct trace_iterator *iter)"
shows up twice in the header file kernel/trace/trace.h

Link: https://lkml.kernel.org/r/20210304092348.208033-1-y.karadz@gmail.com

Signed-off-by: Yordan Karadzhov (VMware) <y.karadz@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-03-04 09:44:47 -05:00
Jens Axboe f01272541d io-wq: ensure all pending work is canceled on exit
If we race on shutting down the io-wq, then we should ensure that any
work that was queued after workers shutdown is canceled. Harden the
add work check a bit too, checking for IO_WQ_BIT_EXIT and cancel if
it's set.

Add a WARN_ON() for having any work before we kill the io-wq context.

Reported-by: syzbot+91b4b56ead187d35c9d3@syzkaller.appspotmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:38:10 -07:00
Jens Axboe e4b4a13f49 io_uring: ensure that threads freeze on suspend
Alex reports that his system fails to suspend using 5.12-rc1, with the
following dump:

[  240.650300] PM: suspend entry (deep)
[  240.650748] Filesystems sync: 0.000 seconds
[  240.725605] Freezing user space processes ...
[  260.739483] Freezing of tasks failed after 20.013 seconds (3 tasks refusing to freeze, wq_busy=0):
[  260.739497] task:iou-mgr-446     state:S stack:    0 pid:  516 ppid:   439 flags:0x00004224
[  260.739504] Call Trace:
[  260.739507]  ? sysvec_apic_timer_interrupt+0xb/0x81
[  260.739515]  ? pick_next_task_fair+0x197/0x1cde
[  260.739519]  ? sysvec_reschedule_ipi+0x2f/0x6a
[  260.739522]  ? asm_sysvec_reschedule_ipi+0x12/0x20
[  260.739525]  ? __schedule+0x57/0x6d6
[  260.739529]  ? del_timer_sync+0xb9/0x115
[  260.739533]  ? schedule+0x63/0xd5
[  260.739536]  ? schedule_timeout+0x219/0x356
[  260.739540]  ? __next_timer_interrupt+0xf1/0xf1
[  260.739544]  ? io_wq_manager+0x73/0xb1
[  260.739549]  ? io_wq_create+0x262/0x262
[  260.739553]  ? ret_from_fork+0x22/0x30
[  260.739557] task:iou-mgr-517     state:S stack:    0 pid:  522 ppid:   439 flags:0x00004224
[  260.739561] Call Trace:
[  260.739563]  ? sysvec_apic_timer_interrupt+0xb/0x81
[  260.739566]  ? pick_next_task_fair+0x16f/0x1cde
[  260.739569]  ? sysvec_apic_timer_interrupt+0xb/0x81
[  260.739571]  ? asm_sysvec_apic_timer_interrupt+0x12/0x20
[  260.739574]  ? __schedule+0x5b7/0x6d6
[  260.739578]  ? del_timer_sync+0x70/0x115
[  260.739581]  ? schedule_timeout+0x211/0x356
[  260.739585]  ? __next_timer_interrupt+0xf1/0xf1
[  260.739588]  ? io_wq_check_workers+0x15/0x11f
[  260.739592]  ? io_wq_manager+0x69/0xb1
[  260.739596]  ? io_wq_create+0x262/0x262
[  260.739600]  ? ret_from_fork+0x22/0x30
[  260.739603] task:iou-wrk-517     state:S stack:    0 pid:  523 ppid:   439 flags:0x00004224
[  260.739607] Call Trace:
[  260.739609]  ? __schedule+0x5b7/0x6d6
[  260.739614]  ? schedule+0x63/0xd5
[  260.739617]  ? schedule_timeout+0x219/0x356
[  260.739621]  ? __next_timer_interrupt+0xf1/0xf1
[  260.739624]  ? task_thread.isra.0+0x148/0x3af
[  260.739628]  ? task_thread_unbound+0xa/0xa
[  260.739632]  ? task_thread_bound+0x7/0x7
[  260.739636]  ? ret_from_fork+0x22/0x30
[  260.739647] OOM killer enabled.
[  260.739648] Restarting tasks ... done.
[  260.740077] PM: suspend exit

Play nice and ensure that any thread we create will call try_to_freeze()
at an opportune time so that memory suspend can proceed. For the io-wq
worker threads, mark them as PF_NOFREEZE. They could potentially be
blocked for a long time.

Reported-by: Alex Xu (Hello71) <alex_y_xu@yahoo.ca>
Tested-by: Alex Xu (Hello71) <alex_y_xu@yahoo.ca>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:38:09 -07:00
Pavel Begunkov b23fcf477f io_uring: remove extra in_idle wake up
io_dismantle_req() is always followed by io_put_task(), which already do
proper in_idle wake ups, so we can skip waking the owner task in
io_dismantle_req(). The rules are simpler now, do io_put_task() shortly
after ending a request, and it will be fine.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:38:07 -07:00
Pavel Begunkov ebf9366707 io_uring: inline __io_queue_async_work()
__io_queue_async_work() is only called from io_queue_async_work(),
inline it.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:38:05 -07:00
Pavel Begunkov f85c310ac3 io_uring: inline io_req_clean_work()
Inline io_req_clean_work(), less code and easier to analyse
tctx dependencies and refs usage.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:38:04 -07:00
Pavel Begunkov 64c7212391 io_uring: choose right tctx->io_wq for try cancel
When we cancel SQPOLL, @task in io_uring_try_cancel_requests() will
differ from current. Use the right tctx from passed in @task, and don't
forget that it can be NULL when the io_uring ctx exits.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:38:03 -07:00
Jens Axboe 3e6a0d3c75 io_uring: fix -EAGAIN retry with IOPOLL
We no longer revert the iovec on -EIOCBQUEUED, see commit ab2125df92,
and this started causing issues for IOPOLL on devies that run out of
request slots. Turns out what outside of needing a revert for those, we
also had a bug where we didn't properly setup retry inside the submission
path. That could cause re-import of the iovec, if any, and that could lead
to spurious results if the application had those allocated on the stack.

Catch -EAGAIN retry and make the iovec stable for IOPOLL, just like we do
for !IOPOLL retries.

Cc: <stable@vger.kernel.org> # 5.9+
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Reported-by: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:38:01 -07:00
Jens Axboe dc7bbc9ef3 io-wq: fix error path leak of buffered write hash map
The 'err' path should include the hash put, we already grabbed a reference
once we get that far.

Fixes: e941894eae ("io-wq: make buffered file write hashed work map per-ctx")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:37:59 -07:00
Pavel Begunkov 16270893d7 io_uring: remove sqo_task
Now, sqo_task is used only for a warning that is not interesting anymore
since sqo_dead is gone, remove all of that including ctx->sqo_task.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:37:57 -07:00
Pavel Begunkov 70aacfe661 io_uring: kill sqo_dead and sqo submission halting
As SQPOLL task doesn't poke into ->sqo_task anymore, there is no need to
kill the sqo when the master task exits. Before it was necessary to
avoid races accessing sqo_task->files with removing them.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
[axboe: don't forget to enable SQPOLL before exit, if started disabled]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:37:55 -07:00
Jens Axboe 1c3b3e6527 io_uring: ignore double poll add on the same waitqueue head
syzbot reports a deadlock, attempting to lock the same spinlock twice:

============================================
WARNING: possible recursive locking detected
5.11.0-syzkaller #0 Not tainted
--------------------------------------------
swapper/1/0 is trying to acquire lock:
ffff88801b2b1130 (&runtime->sleep){..-.}-{2:2}, at: spin_lock include/linux/spinlock.h:354 [inline]
ffff88801b2b1130 (&runtime->sleep){..-.}-{2:2}, at: io_poll_double_wake+0x25f/0x6a0 fs/io_uring.c:4960

but task is already holding lock:
ffff88801b2b3130 (&runtime->sleep){..-.}-{2:2}, at: __wake_up_common_lock+0xb4/0x130 kernel/sched/wait.c:137

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&runtime->sleep);
  lock(&runtime->sleep);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

2 locks held by swapper/1/0:
 #0: ffff888147474908 (&group->lock){..-.}-{2:2}, at: _snd_pcm_stream_lock_irqsave+0x9f/0xd0 sound/core/pcm_native.c:170
 #1: ffff88801b2b3130 (&runtime->sleep){..-.}-{2:2}, at: __wake_up_common_lock+0xb4/0x130 kernel/sched/wait.c:137

stack backtrace:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.11.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0xfa/0x151 lib/dump_stack.c:120
 print_deadlock_bug kernel/locking/lockdep.c:2829 [inline]
 check_deadlock kernel/locking/lockdep.c:2872 [inline]
 validate_chain kernel/locking/lockdep.c:3661 [inline]
 __lock_acquire.cold+0x14c/0x3b4 kernel/locking/lockdep.c:4900
 lock_acquire kernel/locking/lockdep.c:5510 [inline]
 lock_acquire+0x1ab/0x730 kernel/locking/lockdep.c:5475
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151
 spin_lock include/linux/spinlock.h:354 [inline]
 io_poll_double_wake+0x25f/0x6a0 fs/io_uring.c:4960
 __wake_up_common+0x147/0x650 kernel/sched/wait.c:108
 __wake_up_common_lock+0xd0/0x130 kernel/sched/wait.c:138
 snd_pcm_update_state+0x46a/0x540 sound/core/pcm_lib.c:203
 snd_pcm_update_hw_ptr0+0xa75/0x1a50 sound/core/pcm_lib.c:464
 snd_pcm_period_elapsed+0x160/0x250 sound/core/pcm_lib.c:1805
 dummy_hrtimer_callback+0x94/0x1b0 sound/drivers/dummy.c:378
 __run_hrtimer kernel/time/hrtimer.c:1519 [inline]
 __hrtimer_run_queues+0x609/0xe40 kernel/time/hrtimer.c:1583
 hrtimer_run_softirq+0x17b/0x360 kernel/time/hrtimer.c:1600
 __do_softirq+0x29b/0x9f6 kernel/softirq.c:345
 invoke_softirq kernel/softirq.c:221 [inline]
 __irq_exit_rcu kernel/softirq.c:422 [inline]
 irq_exit_rcu+0x134/0x200 kernel/softirq.c:434
 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1100
 </IRQ>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:632
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:29 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline]
RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:137 [inline]
RIP: 0010:acpi_safe_halt drivers/acpi/processor_idle.c:111 [inline]
RIP: 0010:acpi_idle_do_entry+0x1c9/0x250 drivers/acpi/processor_idle.c:516
Code: dd 38 6e f8 84 db 75 ac e8 54 32 6e f8 e8 0f 1c 74 f8 e9 0c 00 00 00 e8 45 32 6e f8 0f 00 2d 4e 4a c5 00 e8 39 32 6e f8 fb f4 <9c> 5b 81 e3 00 02 00 00 fa 31 ff 48 89 de e8 14 3a 6e f8 48 85 db
RSP: 0018:ffffc90000d47d18 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff8880115c3780 RSI: ffffffff89052537 RDI: 0000000000000000
RBP: ffff888141127064 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff81794168 R11: 0000000000000000 R12: 0000000000000001
R13: ffff888141127000 R14: ffff888141127064 R15: ffff888143331804
 acpi_idle_enter+0x361/0x500 drivers/acpi/processor_idle.c:647
 cpuidle_enter_state+0x1b1/0xc80 drivers/cpuidle/cpuidle.c:237
 cpuidle_enter+0x4a/0xa0 drivers/cpuidle/cpuidle.c:351
 call_cpuidle kernel/sched/idle.c:158 [inline]
 cpuidle_idle_call kernel/sched/idle.c:239 [inline]
 do_idle+0x3e1/0x590 kernel/sched/idle.c:300
 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:397
 start_secondary+0x274/0x350 arch/x86/kernel/smpboot.c:272
 secondary_startup_64_no_verify+0xb0/0xbb

which is due to the driver doing poll_wait() twice on the same
wait_queue_head. That is perfectly valid, but from checking the rest
of the kernel tree, it's the only driver that does this.

We can handle this just fine, we just need to ignore the second addition
as we'll get woken just fine on the first one.

Cc: stable@vger.kernel.org # 5.8+
Fixes: 18bceab101 ("io_uring: allow POLL_ADD with double poll_wait() users")
Reported-by: syzbot+28abd693db9e92c160d8@syzkaller.appspotmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:37:14 -07:00
Jens Axboe 3ebba796fa io_uring: ensure that SQPOLL thread is started for exit
If we create it in a disabled state because IORING_SETUP_R_DISABLED is
set on ring creation, we need to ensure that we've kicked the thread if
we're exiting before it's been explicitly disabled. Otherwise we can run
into a deadlock where exit is waiting go park the SQPOLL thread, but the
SQPOLL thread itself is waiting to get a signal to start.

That results in the below trace of both tasks hung, waiting on each other:

INFO: task syz-executor458:8401 blocked for more than 143 seconds.
      Not tainted 5.11.0-next-20210226-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor458 state:D stack:27536 pid: 8401 ppid:  8400 flags:0x00004004
Call Trace:
 context_switch kernel/sched/core.c:4324 [inline]
 __schedule+0x90c/0x21a0 kernel/sched/core.c:5075
 schedule+0xcf/0x270 kernel/sched/core.c:5154
 schedule_timeout+0x1db/0x250 kernel/time/timer.c:1868
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x168/0x270 kernel/sched/completion.c:138
 io_sq_thread_park fs/io_uring.c:7115 [inline]
 io_sq_thread_park+0xd5/0x130 fs/io_uring.c:7103
 io_uring_cancel_task_requests+0x24c/0xd90 fs/io_uring.c:8745
 __io_uring_files_cancel+0x110/0x230 fs/io_uring.c:8840
 io_uring_files_cancel include/linux/io_uring.h:47 [inline]
 do_exit+0x299/0x2a60 kernel/exit.c:780
 do_group_exit+0x125/0x310 kernel/exit.c:922
 __do_sys_exit_group kernel/exit.c:933 [inline]
 __se_sys_exit_group kernel/exit.c:931 [inline]
 __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:931
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x43e899
RSP: 002b:00007ffe89376d48 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00000000004af2f0 RCX: 000000000043e899
RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffffffffffc0 R09: 0000000010000000
R10: 0000000000008011 R11: 0000000000000246 R12: 00000000004af2f0
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001
INFO: task iou-sqp-8401:8402 can't die for more than 143 seconds.
task:iou-sqp-8401    state:D stack:30272 pid: 8402 ppid:  8400 flags:0x00004004
Call Trace:
 context_switch kernel/sched/core.c:4324 [inline]
 __schedule+0x90c/0x21a0 kernel/sched/core.c:5075
 schedule+0xcf/0x270 kernel/sched/core.c:5154
 schedule_timeout+0x1db/0x250 kernel/time/timer.c:1868
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x168/0x270 kernel/sched/completion.c:138
 io_sq_thread+0x27d/0x1ae0 fs/io_uring.c:6717
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
INFO: task iou-sqp-8401:8402 blocked for more than 143 seconds.

Reported-by: syzbot+fb5458330b4442f2090d@syzkaller.appspotmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:37:14 -07:00
Pavel Begunkov 28c4721b80 io_uring: replace cmpxchg in fallback with xchg
io_run_ctx_fallback() can use xchg() instead of cmpxchg(). It's simpler
and faster.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:37:14 -07:00
Pavel Begunkov 2c32395d81 io_uring: fix __tctx_task_work() ctx race
There is an unlikely but possible race using a freed context. That's
because req->task_work.func() can free a request, but we won't
necessarily find a completion in submit_state.comp and so all ctx refs
may be put by the time we do mutex_lock(&ctx->uring_ctx);

There are several reasons why it can miss going through
submit_state.comp: 1) req->task_work.func() didn't complete it itself,
but punted to iowq (e.g. reissue) and it got freed later, or a similar
situation with it overflowing and getting flushed by someone else, or
being submitted to IRQ completion, 2) As we don't hold the uring_lock,
someone else can do io_submit_flush_completions() and put our ref.
3) Bugs and code obscurities, e.g. failing to propagate issue_flags
properly.

One example is as follows

  CPU1                                  |  CPU2
=======================================================================
@req->task_work.func()                  |
  -> @req overflwed,                    |
     so submit_state.comp,nr==0         |
                                        | flush overflows, and free @req
                                        | ctx refs == 0, free it
ctx is dead, but we do                  |
	lock + flush + unlock           |

So take a ctx reference for each new ctx we see in __tctx_task_work(),
and do release it until we do all our flushing.

Fixes: 65453d1efb ("io_uring: enable req cache for task_work items")
Reported-by: syzbot+a157ac7c03a56397f553@syzkaller.appspotmail.com
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
[axboe: fold in my one-liner and fix ref mismatch]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:37:05 -07:00
Jens Axboe 0d30b3e7ee io_uring: kill io_uring_flush()
This was always a weird work-around or file referencing, and we don't
need it anymore. Get rid of it.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:37:03 -07:00
Jens Axboe 914390bcfd io_uring: kill unnecessary io_run_ctx_fallback() in io_ring_exit_work()
We already run the fallback task_work in io_uring_try_cancel_requests(),
no need to duplicate at ring exit explicitly.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:36:28 -07:00
Jens Axboe 5730b27e84 io_uring: move cred assignment into io_issue_sqe()
If we move it in there, then we no longer have to care about it in io-wq.
This means we can drop the cred handling in io-wq, and we can drop the
REQ_F_WORK_INITIALIZED flag and async init functions as that was the last
user of it since we moved to the new workers. Then we can also drop
io_wq_work->creds, and just hold the personality u16 in there instead.

Suggested-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:36:28 -07:00
Jens Axboe 1575f21a09 io_uring: kill unnecessary REQ_F_WORK_INITIALIZED checks
We're no longer checking anything that requires the work item to be
initialized, as we're not carrying any file related state there.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:36:26 -07:00
Jens Axboe 4010fec41f io_uring: remove unused argument 'tsk' from io_req_caches_free()
We prune the full cache regardless, get rid of the dead argument.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:36:24 -07:00
Pavel Begunkov 8452d4a674 io_uring: destroy io-wq on exec
Destroy current's io-wq backend and tctx on __io_uring_task_cancel(),
aka exec(). Looks it's not strictly necessary, because it will be done
at some point when the task dies and changes of creds/files/etc. are
handled, but better to do that earlier to free io-wq and not potentially
lock previous mm and other resources for the time being.

It's safe to do because we wait for all requests of the current task to
complete, so no request will use tctx afterwards. Note, that
io_uring_files_cancel() may leave some requests for later reaping, so it
leaves tctx intact, that's ok as the task is dying anyway.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:36:22 -07:00
Pavel Begunkov ef8eaa4e65 io_uring: warn on not destroyed io-wq
Make sure that we killed an io-wq by the time a task is dead.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:35:00 -07:00
Jens Axboe 1d5f360dd1 io_uring: fix race condition in task_work add and clear
We clear the bit marking the ctx task_work as active after having run
the queued work, but we really should be clearing it before. Otherwise
we can hit a tiny race ala:

CPU0					CPU1
io_task_work_add()			tctx_task_work()
					run_work
	add_to_list
	test_and_set_bit
					clear_bit
		already set

and CPU0 will return thinking the task_work is queued, while in reality
it's already being run. If we hit the condition after __tctx_task_work()
found no more work, but before we've cleared the bit, then we'll end up
thinking it's queued and will be run. In reality it is queued, but we
didn't queue the ctx task_work to ensure that it gets run.

Fixes: 7cbf1722d5 ("io_uring: provide FIFO ordering for task_work")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:35:00 -07:00
Jens Axboe afcc4015d1 io-wq: provide an io_wq_put_and_exit() helper
If we put the io-wq from io_uring, we really want it to exit. Provide
a helper that does that for us. Couple that with not having the manager
hold a reference to the 'wq' and the normal SQPOLL exit will tear down
the io-wq context appropriate.

On the io-wq side, our wq context is per task, so only the task itself
is manipulating ->manager and hence it's safe to check and clear without
any extra locking. We just need to ensure that the manager task stays
around, in case it exits.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:34:39 -07:00
Jens Axboe 8629397e6e io_uring: don't use complete_all() on SQPOLL thread exit
We want to reuse this completion, and a single complete should do just
fine. Ensure that we park ourselves first if requested, as that is what
lead to the initial deadlock in this area. If we've got someone attempting
to park us, then we can't proceed without having them finish first.

Fixes: 37d1e2e364 ("io_uring: move SQPOLL thread io-wq forked worker")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:34:04 -07:00
Pavel Begunkov ba50a036f2 io_uring: run fallback on cancellation
io_uring_try_cancel_requests() matches not only current's requests, but
also of other exiting tasks, so we need to actively cancel them and not
just wait, especially since the function can be called on flush during
do_exit() -> exit_files().
Even if it's not a problem for now, it's much nicer to know that the
function tries to cancel everything it can.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:34:03 -07:00
Jens Axboe e54945ae94 io_uring: SQPOLL stop error handling fixes
If we fail to fork an SQPOLL worker, we can hit cancel, and hence
attempted thread stop, with the thread already being stopped. Ensure
we check for that.

Also guard thread stop fully by the sqd mutex, just like we do for
park.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:34:01 -07:00
Jens Axboe 470ec4ed8c io-wq: fix double put of 'wq' in error path
We are already freeing the wq struct in both spots, so don't put it and
get it freed twice.

Reported-by: syzbot+7bf785eedca35ca05501@syzkaller.appspotmail.com
Fixes: 4fb6ac3262 ("io-wq: improve manager/worker handling over exec")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:34:00 -07:00
Jens Axboe d364d9e5db io-wq: wait for manager exit on wq destroy
The manager waits for the workers, hence the manager is always valid if
workers are running. Now also have wq destroy wait for the manager on
exit, so we now everything is gone.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:33:58 -07:00
Jens Axboe dbf996202e io-wq: rename wq->done completion to wq->started
This is a leftover from a different use cases, it's used to wait for
the manager to startup. Rename it as such.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:32:54 -07:00
Jens Axboe 613eeb600e io-wq: don't ask for a new worker if we're exiting
If we're in the process of shutting down the async context, then don't
create new workers if we already have at least the fixed one.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:32:53 -07:00
Jens Axboe fb3a1f6c74 io-wq: have manager wait for all workers to exit
Instead of having to wait separately on workers and manager, just have
the manager wait on the workers. We use an atomic_t for the reference
here, as we need to start at 0 and allow increment from that. Since the
number of workers is naturally capped by the allowed nr of processes,
and that uses an int, there is no risk of overflow.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-04 06:32:33 -07:00
Zenghui Yu 444d66a23c iommu/vt-d: Fix status code for Allocate/Free PASID command
As per Intel vt-d spec, Rev 3.0 (section 10.4.45 "Virtual Command Response
Register"), the status code of "No PASID available" error in response to
the Allocate PASID command is 2, not 1. The same for "Invalid PASID" error
in response to the Free PASID command.

We will otherwise see confusing kernel log under the command failure from
guest side. Fix it.

Fixes: 24f27d32ab ("iommu/vt-d: Enlightened PASID allocation")
Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Acked-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20210227073909.432-1-yuzenghui@huawei.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2021-03-04 13:32:04 +01:00
Lu Baolu 82c3cefb9f iommu: Don't use lazy flush for untrusted device
The lazy IOTLB flushing setup leaves a time window, in which the device
can still access some system memory, which has already been unmapped by
the device driver. It's not suitable for untrusted devices. A malicious
device might use this to attack the system by obtaining data that it
shouldn't obtain.

Fixes: c588072bba ("iommu/vt-d: Convert intel iommu driver to the iommu ops")
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20210225061454.2864009-1-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2021-03-04 13:22:28 +01:00
Nicolin Chen 765a9d1d02 iommu/tegra-smmu: Fix mc errors on tegra124-nyan
Commit 25938c73cd ("iommu/tegra-smmu: Rework tegra_smmu_probe_device()")
removed certain hack in the tegra_smmu_probe() by relying on IOMMU core to
of_xlate SMMU's SID per device, so as to get rid of tegra_smmu_find() and
tegra_smmu_configure() that are typically done in the IOMMU core also.

This approach works for both existing devices that have DT nodes and other
devices (like PCI device) that don't exist in DT, on Tegra210 and Tegra3
upon testing. However, Page Fault errors are reported on tegra124-Nyan:

  tegra-mc 70019000.memory-controller: display0a: read @0xfe056b40:
	 EMEM address decode error (SMMU translation error [--S])
  tegra-mc 70019000.memory-controller: display0a: read @0xfe056b40:
	 Page fault (SMMU translation error [--S])

After debugging, I found that the mentioned commit changed some function
callback sequence of tegra-smmu's, resulting in enabling SMMU for display
client before display driver gets initialized. I couldn't reproduce exact
same issue on Tegra210 as Tegra124 (arm-32) differs at arch-level code.

Actually this Page Fault is a known issue, as on most of Tegra platforms,
display gets enabled by the bootloader for the splash screen feature, so
it keeps filling the framebuffer memory. A proper fix to this issue is to
1:1 linear map the framebuffer memory to IOVA space so the SMMU will have
the same address as the physical address in its page table. Yet, Thierry
has been working on the solution above for a year, and it hasn't merged.

Therefore, let's partially revert the mentioned commit to fix the errors.

The reason why we do a partial revert here is that we can still set priv
in ->of_xlate() callback for PCI devices. Meanwhile, devices existing in
DT, like display, will go through tegra_smmu_configure() at the stage of
bus_set_iommu() when SMMU gets probed(), as what it did before we merged
the mentioned commit.

Once we have the linear map solution for framebuffer memory, this change
can be cleaned away.

[Big thank to Guillaume who reported and helped debugging/verification]

Fixes: 25938c73cd ("iommu/tegra-smmu: Rework tegra_smmu_probe_device()")
Reported-by: Guillaume Tucker <guillaume.tucker@collabora.com>
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Tested-by: Guillaume Tucker <guillaume.tucker@collabora.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20210218220702.1962-1-nicoleotsuka@gmail.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2021-03-04 13:20:54 +01:00
Andrey Ryabinin 140456f994 iommu/amd: Fix sleeping in atomic in increase_address_space()
increase_address_space() calls get_zeroed_page(gfp) under spin_lock with
disabled interrupts. gfp flags passed to increase_address_space() may allow
sleeping, so it comes to this:

 BUG: sleeping function called from invalid context at mm/page_alloc.c:4342
 in_atomic(): 1, irqs_disabled(): 1, pid: 21555, name: epdcbbf1qnhbsd8

 Call Trace:
  dump_stack+0x66/0x8b
  ___might_sleep+0xec/0x110
  __alloc_pages_nodemask+0x104/0x300
  get_zeroed_page+0x15/0x40
  iommu_map_page+0xdd/0x3e0
  amd_iommu_map+0x50/0x70
  iommu_map+0x106/0x220
  vfio_iommu_type1_ioctl+0x76e/0x950 [vfio_iommu_type1]
  do_vfs_ioctl+0xa3/0x6f0
  ksys_ioctl+0x66/0x70
  __x64_sys_ioctl+0x16/0x20
  do_syscall_64+0x4e/0x100
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fix this by moving get_zeroed_page() out of spin_lock/unlock section.

Fixes: 754265bcab ("iommu/amd: Fix race in increase_address_space()")
Signed-off-by: Andrey Ryabinin <arbn@yandex-team.com>
Acked-by: Will Deacon <will@kernel.org>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210217143004.19165-1-arbn@yandex-team.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2021-03-04 13:15:56 +01:00
Kevin Wang 1aa46901ee drm/amdgpu: fix parameter error of RREG32_PCIE() in amdgpu_regs_pcie
the register offset isn't needed division by 4 to pass RREG32_PCIE()

Signed-off-by: Kevin Wang <kevin1.wang@amd.com>
Reviewed-by: Lijo Lazar <lijo.lazar@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
2021-03-03 23:05:16 -05:00
Colin Ian King b934dd9b44 drm/amd/display: fix the return of the uninitialized value in ret
Currently if stream->signal is neither SIGNAL_TYPE_DISPLAY_PORT_MST or
SIGNAL_TYPE_DISPLAY_PORT then variable ret is uninitialized and this is
checked for > 0 at the end of the function.  Ret should be initialized,
I believe setting it to zero is a correct default.

Addresses-Coverity: ("Uninitialized scalar variable")
Fixes: bd0c064c16 ("drm/amd/display: Add return code instead of boolean for future use")
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2021-03-03 23:05:16 -05:00
Alex Deucher 25951362db drm/amdgpu: enable BACO runpm by default on sienna cichlid and navy flounder
It works fine and was only disabled because primary GPUs
don't enter runpm if there is a console bound to the fbdev due
to the kmap.  This will at least allow runpm on secondary cards.

Reviewed-by: Evan Quan <evan.quan@amd.com>
Reviewed-by: Rajneesh Bhardwaj <rajneesh.bhardwaj@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2021-03-03 23:05:16 -05:00
Evan Quan 6efda16713 drm/amd/pm: correct Arcturus mmTHM_BACO_CNTL register address
Arcturus has a different register address from other SMU V11
ASICs.

Signed-off-by: Evan Quan <evan.quan@amd.com>
Acked-by: Guchun Chen <guchun.chen@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
2021-03-03 23:05:02 -05:00
Alex Deucher 992ace410c drm/amdgpu/swsmu/vangogh: Only use RLCPowerNotify msg for disable
Per discussions with PMFW team, the driver only needs to
notify the PMFW when the RLC is disabled.  The RLC FW will notify
the PMFW directly when it's enabled.

Acked-by: Evan Quan <evan.quan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2021-03-03 22:50:26 -05:00
Alex Deucher e3746696e7 drm/amdgpu/pm: make unsupported power profile messages debug
Making them an error confuses users and the errors are harmless
as not all asics support all profiles.

Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/1488
Acked-by: Nirmoy Das <nirmoy.das@amd.com>
Reviewed-by: Evan Quan <evan.quan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2021-03-03 22:49:44 -05:00
Asher.Song 0c61ac8134 drm/amdgpu:disable VCN for Navi12 SKU
Navi12 0x7360/C7 SKU has no video support, so remove it.

Reviewed-by: Guchun Chen <guchun.chen@amd.com>
Signed-off-by: Asher.Song <Asher.Song@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
2021-03-03 22:48:33 -05:00
Alex Deucher 31ada99bdd drm/amdgpu: Only check for S0ix if AMD_PMC is configured
The S0ix check only makes sense if the AMD PMC driver is
present.  We need to use the legacy S3 pathes when the
PMC driver is not present.

Reviewed-by: Prike Liang <Prike.Liang@amd.com>
Reviewed-by: Rajneesh Bhardwaj <rajneesh.bhardwaj@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
2021-03-03 22:46:55 -05:00
Andy Shevchenko ff70784ab9 ACPI: bus: Constify is_acpi_node() and friends (part 2)
Commit 8b9d680258 ("ACPI: Constify acpi_bus helper functions,
switch to macros") only changed functions for CONFIG_ACPI=y case.
This part adjusts the rest.

Fixes: 8b9d680258 ("ACPI: Constify acpi_bus helper functions, switch to macros")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-03-03 19:50:47 +01:00