Re: [Qemu-devel] [PULL 1/4] curl: do not use aio_context_acquire/release

["Richard W.M. Jones" <rjones@redhat.com>]

Same backtrace, but with some more symbols:

__lll_lock_wait () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:135
135		2: movl	%edx, %eax

(gdb) t a a bt

Thread 3 (Thread 0x7f1d49967700 (LWP 29949)):
#0  0x00007f1d53a39bf9 in syscall ()
    at ../sysdeps/unix/sysv/linux/x86_64/syscall.S:38
#1  0x000055ea5c358856 in qemu_event_wait (val=<optimized out>, f=<optimized out>) at /home/rjones/d/qemu/include/qemu/futex.h:26
#2  0x000055ea5c358856 in qemu_event_wait (ev=ev@entry=0x55ea5cde4ac4 <rcu_call_ready_event>) at util/qemu-thread-posix.c:399
#3  0x000055ea5c3680fe in call_rcu_thread (opaque=<optimized out>)
    at util/rcu.c:249
#4  0x00007f1d57f7fdc5 in start_thread (arg=0x7f1d49967700)
    at pthread_create.c:308
#5  0x00007f1d53a3f73d in clone ()
    at ../sysdeps/unix/sysv/linux/x86_64/clone.S:113

Thread 2 (Thread 0x7f1d46987700 (LWP 29955)):
#0  0x00007f1d57f861bd in __lll_lock_wait ()
    at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:135
#1  0x00007f1d57f81d02 in _L_lock_791 () at /lib64/libpthread.so.0
#2  0x00007f1d57f81c08 in __GI___pthread_mutex_lock (mutex=mutex@entry=0x55ea5c9a2400 <qemu_global_mutex>) at pthread_mutex_lock.c:64
#3  0x000055ea5c3583e9 in qemu_mutex_lock (mutex=mutex@entry=0x55ea5c9a2400 <qemu_global_mutex>) at util/qemu-thread-posix.c:60
#4  0x000055ea5bff512c in qemu_mutex_lock_iothread ()
    at /home/rjones/d/qemu/cpus.c:1565
#5  0x000055ea5c0081c7 in kvm_cpu_exec (cpu=cpu@entry=0x55ea5e7df020)
    at /home/rjones/d/qemu/kvm-all.c:2096
#6  0x000055ea5bff5332 in qemu_kvm_cpu_thread_fn (arg=0x55ea5e7df020)
    at /home/rjones/d/qemu/cpus.c:1118
#7  0x00007f1d57f7fdc5 in start_thread (arg=0x7f1d46987700)
    at pthread_create.c:308
#8  0x00007f1d53a3f73d in clone ()
    at ../sysdeps/unix/sysv/linux/x86_64/clone.S:113

Thread 1 (Thread 0x7f1d5a4e2c00 (LWP 29947)):
#0  0x00007f1d57f861bd in __lll_lock_wait ()
    at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:135
#1  0x00007f1d57f81d02 in _L_lock_791 () at /lib64/libpthread.so.0
#2  0x00007f1d57f81c08 in __GI___pthread_mutex_lock (mutex=mutex@entry=0x55ea5e5ac178) at pthread_mutex_lock.c:64
#3  0x000055ea5c3583e9 in qemu_mutex_lock (mutex=mutex@entry=0x55ea5e5ac178)
    at util/qemu-thread-posix.c:60
#4  0x000055ea5c2fb2d1 in curl_readv_bh_cb (p=0x55ea6013c620)
    at block/curl.c:824
#5  0x000055ea5c352fe1 in aio_bh_poll (bh=0x55ea60eb99d0) at util/async.c:90
#6  0x000055ea5c352fe1 in aio_bh_poll (ctx=ctx@entry=0x55ea5e555970)
    at util/async.c:118
#7  0x000055ea5c3563c4 in aio_poll (ctx=0x55ea5e555970, blocking=blocking@entry=true) at util/aio-posix.c:682
#8  0x000055ea5c2fb09e in curl_init_state (bs=0x55ea5e5a56b0, s=s@entry=0x55ea5e5ab100) at block/curl.c:470
#9  0x000055ea5c2fb39b in curl_readv_bh_cb (p=0x55ea5f650c30)
    at block/curl.c:839
#10 0x000055ea5c352fe1 in aio_bh_poll (bh=0x55ea60eb1910) at util/async.c:90
#11 0x000055ea5c352fe1 in aio_bh_poll (ctx=ctx@entry=0x55ea5e555970)
    at util/async.c:118
#12 0x000055ea5c355f80 in aio_dispatch (ctx=0x55ea5e555970)
    at util/aio-posix.c:429
#13 0x000055ea5c352ebe in aio_ctx_dispatch (source=<optimized out>, callback=<optimized out>, user_data=<optimized out>) at util/async.c:261
#14 0x00007f1d55489d7a in g_main_context_dispatch (context=0x55ea5e555d40)
    at gmain.c:3152
#15 0x00007f1d55489d7a in g_main_context_dispatch (context=context@entry=0x55ea5e555d40) at gmain.c:3767
#16 0x000055ea5c35523c in main_loop_wait () at util/main-loop.c:213
#17 0x000055ea5c35523c in main_loop_wait (timeout=<optimized out>)
    at util/main-loop.c:261
#18 0x000055ea5c35523c in main_loop_wait (nonblocking=nonblocking@entry=0)
    at util/main-loop.c:517
#19 0x000055ea5bfb44a7 in main () at vl.c:1899
#20 0x000055ea5bfb44a7 in main (argc=<optimized out>, argv=<optimized out>, envp=<optimized out>) at vl.c:4717


-- 
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