From: Florian Weimer <fweimer@redhat.com>
To: libc-alpha@sourceware.org
Subject: misc/tst-bz21269 hang on i386
Date: Fri, 09 Jul 2021 11:37:28 +0200 [thread overview]
Message-ID: <87k0lzj09z.fsf@oldenburg.str.redhat.com> (raw)
Thread 1 is spinning in do_test, on line 219
214 asm volatile ("mov %0, %%ss" : : "r" (0x7));
215
216 /* Fire up thread modify_ldt call. */
217 atomic_store (&ftx, 2);
218
219 while (atomic_load (&ftx) != 0)
220 ;
And thread 2 appears to be stuck in the FUTEX_WAIT. ftx has the value
2.
I think this happens if threadproc observes ftx == 1, but the FUTEX_WAKE
has already happened, so the FUTEX_WAIT blocks indefinitely.
Is there a reason why the test doesn't use a proper barrier
for synchronization?
Thanks,
Florian
next reply other threads:[~2021-07-09 9:37 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-09 9:37 Florian Weimer [this message]
2021-07-09 12:51 ` Adhemerval Zanella
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