Commit f3575af1 authored by Marc-André Lureau's avatar Marc-André Lureau Committed by Paolo Bonzini
Browse files

hw/char/serial: retry write if EAGAIN 



If the chardev returns -1 with EAGAIN errno on write(), it should try
to send it again (EINTR is handled by the chardev itself).

This fixes commit 019288bf
"hw/char/serial: Only retry if qemu_chr_fe_write returns 0"

Tested-by: default avatarIgor Mammedov <imammedo@redhat.com>
Signed-off-by: default avatarMarc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20180716110755.12499-1-marcandre.lureau@redhat.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 01478834

hw/char/serial.c

+14 −9
Original line number Diff line number Diff line
@@ -260,7 +260,11 @@ static void serial_xmit(SerialState *s) 
        if (s->mcr & UART_MCR_LOOP) {

            /* in loopback mode, say that we just received a char */

            serial_receive1(s, &s->tsr, 1);

        } else if (qemu_chr_fe_write(&s->chr, &s->tsr, 1) == 0 &&

        } else {

            int rc = qemu_chr_fe_write(&s->chr, &s->tsr, 1);



            if ((rc == 0 ||

                 (rc == -1 && errno == EAGAIN)) &&

                s->tsr_retry < MAX_XMIT_RETRY) {

                assert(s->watch_tag == 0);

                s->watch_tag =
@@ -271,6 +275,7 @@ static void serial_xmit(SerialState *s) 
                    return;

                }

            }

        }

        s->tsr_retry = 0;



        /* Transmit another byte if it is already available. It is only