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|
register: 0.370
TCG: 0.365
performance: 0.351
graphic: 0.346
KVM: 0.345
user-level: 0.340
mistranslation: 0.332
device: 0.326
virtual: 0.318
permissions: 0.316
PID: 0.311
architecture: 0.305
files: 0.294
hypervisor: 0.291
peripherals: 0.282
kernel: 0.276
assembly: 0.275
debug: 0.270
ppc: 0.268
semantic: 0.264
arm: 0.262
boot: 0.260
x86: 0.256
risc-v: 0.243
vnc: 0.241
VMM: 0.237
network: 0.231
socket: 0.231
i386: 0.216
qemu-img create results in tsan warnings
Description of problem:
Running qemu-img w/ tsan enabled results in a bunch of data races reported:
```
Formatting 'delta.img', fmt=qcow2 cluster_size=65536 extended_l2=off compression_type=zlib size=0 backing_file=base.img backing_fmt=raw lazy_refcounts=off refcount_bits=16
==================
WARNING: ThreadSanitizer: data race (pid=217825)
Atomic write of size 8 at 0x7b4800000228 by main thread:
#0 __tsan_atomic64_exchange <null> (qemu-img+0xb6a55)
#1 aio_bh_poll /usr/local/google/home/pefoley/qemu/build/../util/async.c:151:5 (qemu-img+0x239931)
#2 aio_poll /usr/local/google/home/pefoley/qemu/build/../util/aio-posix.c:707:17 (qemu-img+0x220822)
#3 bdrv_create /usr/local/google/home/pefoley/qemu/build/../block.c:549:13 (qemu-img+0xf88b1)
#4 bdrv_img_create /usr/local/google/home/pefoley/qemu/build/../block.c:6911:11 (qemu-img+0x107c1b)
#5 img_create /usr/local/google/home/pefoley/qemu/build/../qemu-img.c:585:5 (qemu-img+0xe2dad)
#6 main /usr/local/google/home/pefoley/qemu/build/../qemu-img.c:5449:20 (qemu-img+0xddfc3)
Previous read of size 8 at 0x7b4800000228 by thread T5 (mutexes: write M42):
#0 aio_bh_enqueue /usr/local/google/home/pefoley/qemu/build/../util/async.c:82:9 (qemu-img+0x239c4c)
#1 qemu_bh_schedule /usr/local/google/home/pefoley/qemu/build/../util/async.c:186:5 (qemu-img+0x239c4c)
#2 worker_thread /usr/local/google/home/pefoley/qemu/build/../util/thread-pool.c:113:9 (qemu-img+0x24fe7c)
#3 qemu_thread_start /usr/local/google/home/pefoley/qemu/build/../util/qemu-thread-posix.c:556:9 (qemu-img+0x225960)
Location is heap block of size 336 at 0x7b4800000180 allocated by main thread:
#0 calloc <null> (qemu-img+0x68ff9)
#1 g_malloc0 <null> (libglib-2.0.so.0+0x59e70)
#2 qemu_init_main_loop /usr/local/google/home/pefoley/qemu/build/../util/main-loop.c:169:24 (qemu-img+0x24bd47)
#3 main /usr/local/google/home/pefoley/qemu/build/../qemu-img.c:5397:5 (qemu-img+0xddcd7)
Mutex M42 (0x7b3800000010) created at:
#0 pthread_mutex_init <null> (qemu-img+0x6bc0f)
#1 qemu_mutex_init /usr/local/google/home/pefoley/qemu/build/../util/qemu-thread-posix.c:57:11 (qemu-img+0x223f69)
#2 thread_pool_init_one /usr/local/google/home/pefoley/qemu/build/../util/thread-pool.c:306:5 (qemu-img+0x24f24d)
#3 thread_pool_new /usr/local/google/home/pefoley/qemu/build/../util/thread-pool.c:319:5 (qemu-img+0x24f24d)
#4 aio_get_thread_pool /usr/local/google/home/pefoley/qemu/build/../util/async.c:390:28 (qemu-img+0x239fd4)
#5 raw_thread_pool_submit /usr/local/google/home/pefoley/qemu/build/../block/file-posix.c:2045:24 (qemu-img+0x1b51f7)
#6 raw_regular_truncate /usr/local/google/home/pefoley/qemu/build/../block/file-posix.c:2231:12 (qemu-img+0x1b51f7)
#7 raw_co_create /usr/local/google/home/pefoley/qemu/build/../block/file-posix.c:2519:14 (qemu-img+0x1b51f7)
#8 raw_co_create_opts /usr/local/google/home/pefoley/qemu/build/../block/file-posix.c:2635:12 (qemu-img+0x1b5678)
#9 bdrv_create_co_entry /usr/local/google/home/pefoley/qemu/build/../block.c:516:11 (qemu-img+0xf87c5)
#10 bdrv_create /usr/local/google/home/pefoley/qemu/build/../block.c:544:9 (qemu-img+0xf87c5)
#11 bdrv_create_file /usr/local/google/home/pefoley/qemu/build/../block.c:734:11 (qemu-img+0xf8d3d)
#12 qcow2_co_create_opts /usr/local/google/home/pefoley/qemu/build/../block/qcow2.c:3842:11 (qemu-img+0x170c63)
#13 bdrv_create_co_entry /usr/local/google/home/pefoley/qemu/build/../block.c:516:11 (qemu-img+0xf8975)
#14 coroutine_trampoline /usr/local/google/home/pefoley/qemu/build/../util/coroutine-ucontext.c:173:9 (qemu-img+0x23d008)
#15 <null> <null> (libc.so.6+0x51a2f)
Thread T5 'worker' (tid=217829, running) created by main thread at:
#0 pthread_create <null> (qemu-img+0x6a49d)
#1 qemu_thread_create /usr/local/google/home/pefoley/qemu/build/../util/qemu-thread-posix.c:596:11 (qemu-img+0x225800)
#2 do_spawn_thread /usr/local/google/home/pefoley/qemu/build/../util/thread-pool.c:134:5 (qemu-img+0x24fac3)
#3 spawn_thread_bh_fn /usr/local/google/home/pefoley/qemu/build/../util/thread-pool.c:142:5 (qemu-img+0x24fac3)
#4 aio_bh_call /usr/local/google/home/pefoley/qemu/build/../util/async.c:141:5 (qemu-img+0x239a96)
#5 aio_bh_poll /usr/local/google/home/pefoley/qemu/build/../util/async.c:169:13 (qemu-img+0x239a96)
#6 aio_poll /usr/local/google/home/pefoley/qemu/build/../util/aio-posix.c:707:17 (qemu-img+0x220822)
#7 bdrv_create /usr/local/google/home/pefoley/qemu/build/../block.c:549:13 (qemu-img+0xf88b1)
#8 bdrv_img_create /usr/local/google/home/pefoley/qemu/build/../block.c:6911:11 (qemu-img+0x107c1b)
#9 img_create /usr/local/google/home/pefoley/qemu/build/../qemu-img.c:585:5 (qemu-img+0xe2dad)
#10 main /usr/local/google/home/pefoley/qemu/build/../qemu-img.c:5449:20 (qemu-img+0xddfc3)
SUMMARY: ThreadSanitizer: data race (/usr/local/google/home/pefoley/qemu/build/qemu-img+0xb6a55) in __tsan_atomic64_exchange
==================
==================
WARNING: ThreadSanitizer: data race (pid=217825)
Write of size 4 at 0x7b1c000005f0 by thread T5 (mutexes: write M42):
#0 worker_thread /usr/local/google/home/pefoley/qemu/build/../util/thread-pool.c:101:20 (qemu-img+0x24fde3)
#1 qemu_thread_start /usr/local/google/home/pefoley/qemu/build/../util/qemu-thread-posix.c:556:9 (qemu-img+0x225960)
Previous read of size 4 at 0x7b1c000005f0 by main thread (mutexes: write M19):
#0 thread_pool_completion_bh /usr/local/google/home/pefoley/qemu/build/../util/thread-pool.c:170:19 (qemu-img+0x24f7ae)
#1 aio_bh_call /usr/local/google/home/pefoley/qemu/build/../util/async.c:141:5 (qemu-img+0x239a96)
#2 aio_bh_poll /usr/local/google/home/pefoley/qemu/build/../util/async.c:169:13 (qemu-img+0x239a96)
#3 aio_poll /usr/local/google/home/pefoley/qemu/build/../util/aio-posix.c:707:17 (qemu-img+0x220822)
#4 bdrv_create /usr/local/google/home/pefoley/qemu/build/../block.c:549:13 (qemu-img+0xf88b1)
#5 bdrv_img_create /usr/local/google/home/pefoley/qemu/build/../block.c:6911:11 (qemu-img+0x107c1b)
#6 img_create /usr/local/google/home/pefoley/qemu/build/../qemu-img.c:585:5 (qemu-img+0xe2dad)
#7 main /usr/local/google/home/pefoley/qemu/build/../qemu-img.c:5449:20 (qemu-img+0xddfc3)
Location is heap block of size 104 at 0x7b1c000005b0 allocated by thread T4:
#0 malloc <null> (qemu-img+0x68e0d)
#1 g_malloc <null> (libglib-2.0.so.0+0x59e18)
#2 thread_pool_submit_aio /usr/local/google/home/pefoley/qemu/build/../util/thread-pool.c:249:11 (qemu-img+0x24edc8)
#3 thread_pool_submit_co /usr/local/google/home/pefoley/qemu/build/../util/thread-pool.c:287:5 (qemu-img+0x24f0fe)
#4 raw_thread_pool_submit /usr/local/google/home/pefoley/qemu/build/../block/file-posix.c:2046:12 (qemu-img+0x1b5334)
#5 raw_regular_truncate /usr/local/google/home/pefoley/qemu/build/../block/file-posix.c:2231:12 (qemu-img+0x1b5334)
#6 raw_co_create /usr/local/google/home/pefoley/qemu/build/../block/file-posix.c:2562:14 (qemu-img+0x1b5334)
#7 raw_co_create_opts /usr/local/google/home/pefoley/qemu/build/../block/file-posix.c:2635:12 (qemu-img+0x1b5678)
#8 bdrv_create_co_entry /usr/local/google/home/pefoley/qemu/build/../block.c:516:11 (qemu-img+0xf87c5)
#9 bdrv_create /usr/local/google/home/pefoley/qemu/build/../block.c:544:9 (qemu-img+0xf87c5)
#10 bdrv_create_file /usr/local/google/home/pefoley/qemu/build/../block.c:734:11 (qemu-img+0xf8d3d)
#11 qcow2_co_create_opts /usr/local/google/home/pefoley/qemu/build/../block/qcow2.c:3842:11 (qemu-img+0x170c63)
#12 bdrv_create_co_entry /usr/local/google/home/pefoley/qemu/build/../block.c:516:11 (qemu-img+0xf8975)
#13 coroutine_trampoline /usr/local/google/home/pefoley/qemu/build/../util/coroutine-ucontext.c:173:9 (qemu-img+0x23d008)
#14 <null> <null> (libc.so.6+0x51a2f)
Mutex M42 (0x7b3800000010) created at:
#0 pthread_mutex_init <null> (qemu-img+0x6bc0f)
#1 qemu_mutex_init /usr/local/google/home/pefoley/qemu/build/../util/qemu-thread-posix.c:57:11 (qemu-img+0x223f69)
#2 thread_pool_init_one /usr/local/google/home/pefoley/qemu/build/../util/thread-pool.c:306:5 (qemu-img+0x24f24d)
#3 thread_pool_new /usr/local/google/home/pefoley/qemu/build/../util/thread-pool.c:319:5 (qemu-img+0x24f24d)
#4 aio_get_thread_pool /usr/local/google/home/pefoley/qemu/build/../util/async.c:390:28 (qemu-img+0x239fd4)
#5 raw_thread_pool_submit /usr/local/google/home/pefoley/qemu/build/../block/file-posix.c:2045:24 (qemu-img+0x1b51f7)
#6 raw_regular_truncate /usr/local/google/home/pefoley/qemu/build/../block/file-posix.c:2231:12 (qemu-img+0x1b51f7)
#7 raw_co_create /usr/local/google/home/pefoley/qemu/build/../block/file-posix.c:2519:14 (qemu-img+0x1b51f7)
#8 raw_co_create_opts /usr/local/google/home/pefoley/qemu/build/../block/file-posix.c:2635:12 (qemu-img+0x1b5678)
#9 bdrv_create_co_entry /usr/local/google/home/pefoley/qemu/build/../block.c:516:11 (qemu-img+0xf87c5)
#10 bdrv_create /usr/local/google/home/pefoley/qemu/build/../block.c:544:9 (qemu-img+0xf87c5)
#11 bdrv_create_file /usr/local/google/home/pefoley/qemu/build/../block.c:734:11 (qemu-img+0xf8d3d)
#12 qcow2_co_create_opts /usr/local/google/home/pefoley/qemu/build/../block/qcow2.c:3842:11 (qemu-img+0x170c63)
#13 bdrv_create_co_entry /usr/local/google/home/pefoley/qemu/build/../block.c:516:11 (qemu-img+0xf8975)
#14 coroutine_trampoline /usr/local/google/home/pefoley/qemu/build/../util/coroutine-ucontext.c:173:9 (qemu-img+0x23d008)
#15 <null> <null> (libc.so.6+0x51a2f)
Mutex M19 (0x7b48000001e0) created at:
#0 pthread_mutex_init <null> (qemu-img+0x6bc0f)
#1 qemu_rec_mutex_init /usr/local/google/home/pefoley/qemu/build/../util/qemu-thread-posix.c:120:11 (qemu-img+0x224625)
#2 aio_context_new /usr/local/google/home/pefoley/qemu/build/../util/async.c:555:5 (qemu-img+0x23a226)
#3 qemu_init_main_loop /usr/local/google/home/pefoley/qemu/build/../util/main-loop.c:169:24 (qemu-img+0x24bd47)
#4 main /usr/local/google/home/pefoley/qemu/build/../qemu-img.c:5397:5 (qemu-img+0xddcd7)
Thread T5 'worker' (tid=217829, running) created by main thread at:
#0 pthread_create <null> (qemu-img+0x6a49d)
#1 qemu_thread_create /usr/local/google/home/pefoley/qemu/build/../util/qemu-thread-posix.c:596:11 (qemu-img+0x225800)
#2 do_spawn_thread /usr/local/google/home/pefoley/qemu/build/../util/thread-pool.c:134:5 (qemu-img+0x24fac3)
#3 spawn_thread_bh_fn /usr/local/google/home/pefoley/qemu/build/../util/thread-pool.c:142:5 (qemu-img+0x24fac3)
#4 aio_bh_call /usr/local/google/home/pefoley/qemu/build/../util/async.c:141:5 (qemu-img+0x239a96)
#5 aio_bh_poll /usr/local/google/home/pefoley/qemu/build/../util/async.c:169:13 (qemu-img+0x239a96)
#6 aio_poll /usr/local/google/home/pefoley/qemu/build/../util/aio-posix.c:707:17 (qemu-img+0x220822)
#7 bdrv_create /usr/local/google/home/pefoley/qemu/build/../block.c:549:13 (qemu-img+0xf88b1)
#8 bdrv_img_create /usr/local/google/home/pefoley/qemu/build/../block.c:6911:11 (qemu-img+0x107c1b)
#9 img_create /usr/local/google/home/pefoley/qemu/build/../qemu-img.c:585:5 (qemu-img+0xe2dad)
#10 main /usr/local/google/home/pefoley/qemu/build/../qemu-img.c:5449:20 (qemu-img+0xddfc3)
Thread T4 (tid=0, running) created by main thread at:
#0 on_new_fiber /usr/local/google/home/pefoley/qemu/build/../util/coroutine-ucontext.c:90:25 (qemu-img+0x23cead)
#1 qemu_coroutine_new /usr/local/google/home/pefoley/qemu/build/../util/coroutine-ucontext.c:219:5 (qemu-img+0x23cead)
#2 qemu_coroutine_create /usr/local/google/home/pefoley/qemu/build/../util/qemu-coroutine.c:75:14 (qemu-img+0x24c7be)
#3 bdrv_create /usr/local/google/home/pefoley/qemu/build/../block.c:546:14 (qemu-img+0xf8884)
#4 bdrv_img_create /usr/local/google/home/pefoley/qemu/build/../block.c:6911:11 (qemu-img+0x107c1b)
#5 img_create /usr/local/google/home/pefoley/qemu/build/../qemu-img.c:585:5 (qemu-img+0xe2dad)
#6 main /usr/local/google/home/pefoley/qemu/build/../qemu-img.c:5449:20 (qemu-img+0xddfc3)
SUMMARY: ThreadSanitizer: data race /usr/local/google/home/pefoley/qemu/build/../util/thread-pool.c:101:20 in worker_thread
==================
==================
WARNING: ThreadSanitizer: data race (pid=217825)
Atomic write of size 4 at 0x7b0c000000e8 by thread T5 (mutexes: write M42):
#0 __tsan_atomic32_fetch_or <null> (qemu-img+0xb9ec1)
#1 aio_bh_enqueue /usr/local/google/home/pefoley/qemu/build/../util/async.c:80:17 (qemu-img+0x239c23)
#2 qemu_bh_schedule /usr/local/google/home/pefoley/qemu/build/../util/async.c:186:5 (qemu-img+0x239c23)
#3 worker_thread /usr/local/google/home/pefoley/qemu/build/../util/thread-pool.c:113:9 (qemu-img+0x24fe7c)
#4 qemu_thread_start /usr/local/google/home/pefoley/qemu/build/../util/qemu-thread-posix.c:556:9 (qemu-img+0x225960)
Previous read of size 4 at 0x7b0c000000e8 by main thread:
#0 aio_compute_bh_timeout /usr/local/google/home/pefoley/qemu/build/../util/async.c:209:18 (qemu-img+0x239e7f)
#1 aio_compute_timeout /usr/local/google/home/pefoley/qemu/build/../util/async.c:232:15 (qemu-img+0x239e7f)
#2 aio_poll /usr/local/google/home/pefoley/qemu/build/../util/aio-posix.c:624:26 (qemu-img+0x21f9c2)
#3 bdrv_create /usr/local/google/home/pefoley/qemu/build/../block.c:549:13 (qemu-img+0xf88b1)
#4 bdrv_img_create /usr/local/google/home/pefoley/qemu/build/../block.c:6911:11 (qemu-img+0x107c1b)
#5 img_create /usr/local/google/home/pefoley/qemu/build/../qemu-img.c:585:5 (qemu-img+0xe2dad)
#6 main /usr/local/google/home/pefoley/qemu/build/../qemu-img.c:5449:20 (qemu-img+0xddfc3)
Location is heap block of size 48 at 0x7b0c000000c0 allocated by thread T4:
#0 malloc <null> (qemu-img+0x68e0d)
#1 g_malloc <null> (libglib-2.0.so.0+0x59e18)
#2 thread_pool_init_one /usr/local/google/home/pefoley/qemu/build/../util/thread-pool.c:305:27 (qemu-img+0x24f235)
#3 thread_pool_new /usr/local/google/home/pefoley/qemu/build/../util/thread-pool.c:319:5 (qemu-img+0x24f235)
#4 aio_get_thread_pool /usr/local/google/home/pefoley/qemu/build/../util/async.c:390:28 (qemu-img+0x239fd4)
#5 raw_thread_pool_submit /usr/local/google/home/pefoley/qemu/build/../block/file-posix.c:2045:24 (qemu-img+0x1b51f7)
#6 raw_regular_truncate /usr/local/google/home/pefoley/qemu/build/../block/file-posix.c:2231:12 (qemu-img+0x1b51f7)
#7 raw_co_create /usr/local/google/home/pefoley/qemu/build/../block/file-posix.c:2519:14 (qemu-img+0x1b51f7)
#8 raw_co_create_opts /usr/local/google/home/pefoley/qemu/build/../block/file-posix.c:2635:12 (qemu-img+0x1b5678)
#9 bdrv_create_co_entry /usr/local/google/home/pefoley/qemu/build/../block.c:516:11 (qemu-img+0xf87c5)
#10 bdrv_create /usr/local/google/home/pefoley/qemu/build/../block.c:544:9 (qemu-img+0xf87c5)
#11 bdrv_create_file /usr/local/google/home/pefoley/qemu/build/../block.c:734:11 (qemu-img+0xf8d3d)
#12 qcow2_co_create_opts /usr/local/google/home/pefoley/qemu/build/../block/qcow2.c:3842:11 (qemu-img+0x170c63)
#13 bdrv_create_co_entry /usr/local/google/home/pefoley/qemu/build/../block.c:516:11 (qemu-img+0xf8975)
#14 coroutine_trampoline /usr/local/google/home/pefoley/qemu/build/../util/coroutine-ucontext.c:173:9 (qemu-img+0x23d008)
#15 <null> <null> (libc.so.6+0x51a2f)
Mutex M42 (0x7b3800000010) created at:
#0 pthread_mutex_init <null> (qemu-img+0x6bc0f)
#1 qemu_mutex_init /usr/local/google/home/pefoley/qemu/build/../util/qemu-thread-posix.c:57:11 (qemu-img+0x223f69)
#2 thread_pool_init_one /usr/local/google/home/pefoley/qemu/build/../util/thread-pool.c:306:5 (qemu-img+0x24f24d)
#3 thread_pool_new /usr/local/google/home/pefoley/qemu/build/../util/thread-pool.c:319:5 (qemu-img+0x24f24d)
#4 aio_get_thread_pool /usr/local/google/home/pefoley/qemu/build/../util/async.c:390:28 (qemu-img+0x239fd4)
#5 raw_thread_pool_submit /usr/local/google/home/pefoley/qemu/build/../block/file-posix.c:2045:24 (qemu-img+0x1b51f7)
#6 raw_regular_truncate /usr/local/google/home/pefoley/qemu/build/../block/file-posix.c:2231:12 (qemu-img+0x1b51f7)
#7 raw_co_create /usr/local/google/home/pefoley/qemu/build/../block/file-posix.c:2519:14 (qemu-img+0x1b51f7)
#8 raw_co_create_opts /usr/local/google/home/pefoley/qemu/build/../block/file-posix.c:2635:12 (qemu-img+0x1b5678)
#9 bdrv_create_co_entry /usr/local/google/home/pefoley/qemu/build/../block.c:516:11 (qemu-img+0xf87c5)
#10 bdrv_create /usr/local/google/home/pefoley/qemu/build/../block.c:544:9 (qemu-img+0xf87c5)
#11 bdrv_create_file /usr/local/google/home/pefoley/qemu/build/../block.c:734:11 (qemu-img+0xf8d3d)
#12 qcow2_co_create_opts /usr/local/google/home/pefoley/qemu/build/../block/qcow2.c:3842:11 (qemu-img+0x170c63)
#13 bdrv_create_co_entry /usr/local/google/home/pefoley/qemu/build/../block.c:516:11 (qemu-img+0xf8975)
#14 coroutine_trampoline /usr/local/google/home/pefoley/qemu/build/../util/coroutine-ucontext.c:173:9 (qemu-img+0x23d008)
#15 <null> <null> (libc.so.6+0x51a2f)
Thread T5 'worker' (tid=217829, running) created by main thread at:
#0 pthread_create <null> (qemu-img+0x6a49d)
#1 qemu_thread_create /usr/local/google/home/pefoley/qemu/build/../util/qemu-thread-posix.c:596:11 (qemu-img+0x225800)
#2 do_spawn_thread /usr/local/google/home/pefoley/qemu/build/../util/thread-pool.c:134:5 (qemu-img+0x24fac3)
#3 spawn_thread_bh_fn /usr/local/google/home/pefoley/qemu/build/../util/thread-pool.c:142:5 (qemu-img+0x24fac3)
#4 aio_bh_call /usr/local/google/home/pefoley/qemu/build/../util/async.c:141:5 (qemu-img+0x239a96)
#5 aio_bh_poll /usr/local/google/home/pefoley/qemu/build/../util/async.c:169:13 (qemu-img+0x239a96)
#6 aio_poll /usr/local/google/home/pefoley/qemu/build/../util/aio-posix.c:707:17 (qemu-img+0x220822)
#7 bdrv_create /usr/local/google/home/pefoley/qemu/build/../block.c:549:13 (qemu-img+0xf88b1)
#8 bdrv_img_create /usr/local/google/home/pefoley/qemu/build/../block.c:6911:11 (qemu-img+0x107c1b)
#9 img_create /usr/local/google/home/pefoley/qemu/build/../qemu-img.c:585:5 (qemu-img+0xe2dad)
#10 main /usr/local/google/home/pefoley/qemu/build/../qemu-img.c:5449:20 (qemu-img+0xddfc3)
Thread T4 (tid=0, running) created by main thread at:
#0 on_new_fiber /usr/local/google/home/pefoley/qemu/build/../util/coroutine-ucontext.c:90:25 (qemu-img+0x23cead)
#1 qemu_coroutine_new /usr/local/google/home/pefoley/qemu/build/../util/coroutine-ucontext.c:219:5 (qemu-img+0x23cead)
#2 qemu_coroutine_create /usr/local/google/home/pefoley/qemu/build/../util/qemu-coroutine.c:75:14 (qemu-img+0x24c7be)
#3 bdrv_create /usr/local/google/home/pefoley/qemu/build/../block.c:546:14 (qemu-img+0xf8884)
#4 bdrv_img_create /usr/local/google/home/pefoley/qemu/build/../block.c:6911:11 (qemu-img+0x107c1b)
#5 img_create /usr/local/google/home/pefoley/qemu/build/../qemu-img.c:585:5 (qemu-img+0xe2dad)
#6 main /usr/local/google/home/pefoley/qemu/build/../qemu-img.c:5449:20 (qemu-img+0xddfc3)
SUMMARY: ThreadSanitizer: data race (/usr/local/google/home/pefoley/qemu/build/qemu-img+0xb9ec1) in __tsan_atomic32_fetch_or
==================
ThreadSanitizer: reported 3 warnings
```
Steps to reproduce:
1. ./configure --target-list=x86_64-softmmu --enable-tsan --cc=clang --cxx=clang++
2. make -j12
3. touch base.img
4. build/qemu-img create -b base.img -f qcow2 -F raw delta.img
./configure --target-list=x86_64-softmmu --enable-tsan --cc=clang --cxx=clang++
touch base.img
build/qemu-img create -b base.img -f qcow2 -F raw delta.img
|