| Message ID | CAJwJo6YK_QU0SGC34M8bkvj3o8QHxxT1sZvXV5dkm=_LkThutw@mail.gmail.com |
|---|---|
| State | New |
| Series | "zdtm/static/fd failure on aarch64" |
| Headers | show |
diff --git a/test/zdtm/lib/lock.h b/test/zdtm/lib/lock.h index 9c0831d461c1..68f922e9025c 100644 --- a/test/zdtm/lib/lock.h +++ b/test/zdtm/lib/lock.h @@ -145,7 +145,8 @@ static void inline mutex_lock(mutex_t *m) while ((c = atomic_inc(&m->raw)) != 0) { ret = sys_futex(&m->raw, FUTEX_WAIT, c + 1, NULL, NULL, 0); if (ret < 0) - pr_perror("futex"); + pr_perror("futex *%p = %d, c = %u", + &m->raw, atomic_get(&m->raw), c); BUG_ON(ret < 0 && errno != EWOULDBLOCK); } }
On Mon, Jun 11, 2018 at 09:55:53PM +0100, Dmitry Safonov wrote: > 2018-06-11 21:34 GMT+01:00 Adrian Reber <adrian@lisas.de>: > > On Mon, Jun 11, 2018 at 09:19:21PM +0100, Dmitry Safonov wrote: > >> I'm awfully sorry about asking you so many times.. > >> Maybe the thing is in sizeof(unsigned int) != 4 on arm64? > >> > >> Returning back to the first version + correcting definition for syscall. > > > > This was also something I was suspecting, that the syscall is not done > > correctly, but your patch does not help. Same result: > > > > 5085 dup3(4, 0, 0) = 0 > > 5085 close(4) = 0 > > 5085 mmap(NULL, 65536, PROT_READ|PROT_WRITE, MAP_SHARED|MAP_ANONYMOUS, 0, 0) = 0xffff97050000 > > 5085 clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0xffff970b2dd0) = 5086 > > 5085 futex(0xffff97050000, FUTEX_WAIT, 0, NULL <unfinished ...> > > 5086 setsid() = 5086 > > 5086 rt_sigaction(SIGCHLD, {SIG_DFL, [], SA_RESTART}, NULL, 8) = 0 > > 5086 mmap(NULL, 65536, PROT_READ|PROT_WRITE, MAP_SHARED|MAP_ANONYMOUS, -1, 0) = 0xffff96eb0000 > > 5086 futex(0xffff96eb0000, FUTEX_WAIT, 2531983361, NULL) = -1 EAGAIN (Resource temporarily unavailable) > > 5086 brk(NULL) = 0x2e920000 > > 5086 brk(0x2e950000) = 0x2e950000 > > 5086 brk(NULL) = 0x2e950000 > > 5086 openat(AT_FDCWD, "/etc/localtime", O_RDONLY|O_CLOEXEC) = 4 > > 5086 fstat(4, {st_mode=S_IFREG|0644, st_size=3519, ...}) = 0 > > 5086 fstat(4, {st_mode=S_IFREG|0644, st_size=3519, ...}) = 0 > > 5086 mmap(NULL, 65536, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xffff96ea0000 > > 5086 read(4, "TZif2\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\4\0\0\0\4\0\0\0\0"..., 8192) = 3519 > > 5086 lseek(4, -2252, SEEK_CUR) = 1267 > > 5086 read(4, "TZif2\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\5\0\0\0\5\0\0\0\0"..., 8192) = 2252 > > 5086 close(4) = 0 > > 5086 munmap(0xffff96ea0000, 65536) = 0 > > 5086 write(2, "16:31:33.969: 5086: ERR: ../lib"..., 99) = 99 > > 5086 futex(0xffff96eb0000, FUTEX_WAIT, 2531983361, NULL) = -1 EAGAIN (Resource temporarily unavailable) > > 5086 newfstatat(AT_FDCWD, "/etc/localtime", {st_mode=S_IFREG|0644, st_size=3519, ...}, 0) = 0 > > 5086 write(2, "16:31:33.971: 5086: ERR: ../lib"..., 99) = 99 > > 5086 futex(0xffff96eb0000, FUTEX_WAIT, 2531983361, NULL) = -1 EAGAIN (Resource temporarily unavailable) > > 5086 newfstatat(AT_FDCWD, "/etc/localtime", {st_mode=S_IFREG|0644, st_size=3519, ...}, 0) = 0 > > 5086 write(2, "16:31:33.971: 5086: ERR: ../lib"..., 99) = 99 > > On the top of the last one - let's add some debugging. > It looks like the third parameter of futex() has lower bits set correctly, > but the upper contains a garbage. > It might happen if futex is not aligned on 4 bytes in memory, IIRC.. > Let's see what will debug patch result in. Output is always like this: 02:20:50.173: 11691: ERR: ../lib/lock.h:149: futex *0xffff86100000 = 0, c = 2249195520 (errno = 11 (Resource temporarily unavailable)) 11691 mmap(NULL, 65536, PROT_READ|PROT_WRITE, MAP_SHARED|MAP_ANONYMOUS, -1, 0) = 0xffff86100000 11691 futex(0xffff86100000, FUTEX_WAIT, 2249195521, NULL) = -1 EAGAIN (Resource temporarily unavailable) 11691 brk(NULL) = 0x149f0000 11691 brk(0x14a20000) = 0x14a20000 11691 brk(NULL) = 0x14a20000 11691 openat(AT_FDCWD, "/etc/localtime", O_RDONLY|O_CLOEXEC) = 4 11691 fstat(4, {st_mode=S_IFREG|0644, st_size=3519, ...}) = 0 11691 fstat(4, {st_mode=S_IFREG|0644, st_size=3519, ...}) = 0 11691 mmap(NULL, 65536, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xffff860f0000 11691 read(4, "TZif2\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\4\0\0\0\4\0\0\0\0"..., 8192) = 3519 11691 lseek(4, -2252, SEEK_CUR) = 1267 11691 read(4, "TZif2\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\5\0\0\0\5\0\0\0\0"..., 8192) = 2252 11691 close(4) = 0 11691 munmap(0xffff860f0000, 65536) = 0 11691 write(2, "02:20:50.173: 11691: ERR: ../lib"..., 135) = 135 11691 futex(0xffff86100000, FUTEX_WAIT, 2249195521, NULL) = -1 EAGAIN (Resource temporarily unavailable) 11691 newfstatat(AT_FDCWD, "/etc/localtime", {st_mode=S_IFREG|0644, st_size=3519, ...}, 0) = 0 11691 write(2, "02:20:50.175: 11691: ERR: ../lib"..., 135) = 135 How I understand it is that atomic_inc() should return the new value but the returned value is completely different from what atomic_get() returns, right? Adrian