Re: [PATCH] tools: hv: handle EINTR in hv_fcopy_daemon

From: Vitaly Kuznetsov
Date: Fri Aug 25 2017 - 08:27:37 EST


Olaf Hering <olaf@xxxxxxxxx> writes:

> If strace attaches to the daemon pread returns with EINTR, and the
> process exits. Catch this case and continue with the next iteration.
>
> Signed-off-by: Olaf Hering <olaf@xxxxxxxxx>
> ---
> tools/hv/hv_fcopy_daemon.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/tools/hv/hv_fcopy_daemon.c b/tools/hv/hv_fcopy_daemon.c
> index c273dd34d144..574e6bf5865c 100644
> --- a/tools/hv/hv_fcopy_daemon.c
> +++ b/tools/hv/hv_fcopy_daemon.c
> @@ -201,6 +201,8 @@ int main(int argc, char *argv[])
> ssize_t len;
> len = pread(fcopy_fd, &buffer, sizeof(buffer), 0);
> if (len < 0) {
> + if (errno == EINTR)
> + continue;
> syslog(LOG_ERR, "pread failed: %s", strerror(errno));
> exit(EXIT_FAILURE);
> }

Shall we request SA_RESTART with sigaction() in all three daemons instead?

--
Vitaly