On 2023-06-02 10:41:57+0800, Zhangjin Wu wrote:
> Hi, Willy
>
> What about this one for 2023xxxx-nolibc-rv32+stkp6?
>
> @Thomas, welcome your Reviewed-by If it is ok for you ;-)
Indeed, good catch!
Reviewed-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
> Best regards,
> Zhangjin
>
> > running nolibc-test with glibc on x86_64 got such print issue:
> >
> > 29 execve_root = -1 EACCES [OK]
> > 30 fork30 fork = 0 [OK]
> > 31 getdents64_root = 712 [OK]
> >
> > The fork test case has three printf calls:
> >
> > (1) llen += printf("%d %s", test, #name);
> > (2) llen += printf(" = %d %s ", expr, errorname(errno));
> > (3) llen += pad_spc(llen, 64, "[FAIL]\n"); --> vfprintf()
> >
> > In the following scene, the above issue happens:
> >
> > (a) The parent calls (1)
> > (b) The parent calls fork()
> > (c) The child runs and shares the print buffer of (1)
> > (d) The child exits, flushs the print buffer and closes its own stdout/stderr
> > * "30 fork" is printed at the first time.
> > (e) The parent calls (2) and (3), with "\n" in (3), it flushs the whole buffer
> > * "30 fork = 0 ..." is printed
> >
> > Therefore, there are two "30 fork" in the stdout.
> >
> > Between (a) and (b), if flush the stdout (and the sterr), the child in
> > stage (c) will not be able to 'see' the print buffer.
> >
> > Signed-off-by: Zhangjin Wu <falcon@xxxxxxxxxxx>
> > ---
> > tools/testing/selftests/nolibc/nolibc-test.c | 8 +++++++-
> > 1 file changed, 7 insertions(+), 1 deletion(-)
> >
> > diff --git a/tools/testing/selftests/nolibc/nolibc-test.c b/tools/testing/selftests/nolibc/nolibc-test.c
> > index 7de46305f419..88323a60aa4a 100644
> > --- a/tools/testing/selftests/nolibc/nolibc-test.c
> > +++ b/tools/testing/selftests/nolibc/nolibc-test.c
> > @@ -486,7 +486,13 @@ static int test_getpagesize(void)
> > static int test_fork(void)
> > {
> > int status;
> > - pid_t pid = fork();
> > + pid_t pid;
> > +
> > + /* flush the printf buffer to avoid child flush it */
> > + fflush(stdout);
> > + fflush(stderr);
> > +
> > + pid = fork();
> >
> > switch (pid) {
> > case -1:
> > --
> > 2.25.1
> >
> >
