On 22/05/20 18:07, Robert Foley wrote: > For example: > WARNING: ThreadSanitizer: data race (pid=35425) > Write of size 4 at 0x7bbc000000ac by main thread (mutexes: write M875): > #0 cpu_reset_interrupt hw/core/cpu.c:107:28 (qemu-system-aarch64+0x843790) > #1 arm_cpu_set_irq target/arm/cpu.c (qemu-system-aarch64+0x616265) > #2 qemu_set_irq hw/core/irq.c:44:5 (qemu-system-aarch64+0x8462ca) > Previous atomic read of size 4 at 0x7bbc000000ac by thread T6: > #0 __tsan_atomic32_load <null> (qemu-system-aarch64+0x394c1c) > #1 cpu_handle_interrupt accel/tcg/cpu-exec.c:534:9 > (qemu-system-aarch64+0x4b7e79) > #2 cpu_exec accel/tcg/cpu-exec.c:720:17 (qemu-system-aarch64+0x4b7e79) > or > WARNING: ThreadSanitizer: data race (pid=25425) > Read of size 8 at 0x7f8ad8e138d0 by thread T10: > #0 tb_lookup_cmp accel/tcg/cpu-exec.c:307:13 > (qemu-system-aarch64+0x4ac4d2) > #1 qht_do_lookup util/qht.c:502:34 (qemu-system-aarch64+0xd05264) > Previous write of size 8 at 0x7f8ad8e138d0 by thread T15 (mutexes: write > M728311726235541804): > #0 tb_link_page accel/tcg/translate-all.c:1625:26 > (qemu-system-aarch64+0x4b0bf2) > #1 tb_gen_code accel/tcg/translate-all.c:1865:19 > (qemu-system-aarch64+0x4b0bf2) > #2 tb_find accel/tcg/cpu-exec.c:407:14 (qemu-system-aarch64+0x4ad77c) > > Cc: Richard Henderson <richard.hender...@linaro.org> > Cc: Paolo Bonzini <pbonz...@redhat.com> > Signed-off-by: Robert Foley <robert.fo...@linaro.org> > --- > accel/tcg/tcg-all.c | 4 ++-- > accel/tcg/tcg-runtime.c | 7 ++++++- > accel/tcg/translate-all.c | 6 +++++- > hw/core/cpu.c | 2 +- > 4 files changed, 14 insertions(+), 5 deletions(-) > > diff --git a/accel/tcg/tcg-all.c b/accel/tcg/tcg-all.c > index 3b4fda5640..f94ea4c4b3 100644 > --- a/accel/tcg/tcg-all.c > +++ b/accel/tcg/tcg-all.c > @@ -54,8 +54,8 @@ static void tcg_handle_interrupt(CPUState *cpu, int mask) > int old_mask; > g_assert(qemu_mutex_iothread_locked()); > > - old_mask = cpu->interrupt_request; > - cpu->interrupt_request |= mask; > + old_mask = atomic_read(&cpu->interrupt_request); > + atomic_or(&cpu->interrupt_request, mask);
You can use atomic_fetch_or here. Paolo