Re: [Qemu-devel] [PATCH] serial: fix multi-pci card error cleanup.

[Paolo Bonzini <pbonzini@redhat.com>]

On 06/05/2015 13:31, Gerd Hoffmann wrote:
> Put the number of serial ports into a local variable in
> multi_serial_pci_realize, then increment the port count
> (pci->ports) as we initialize the serial port cores.
> 
> Now pci->ports always holds the number of successfully
> initialized ports and we can use multi_serial_pci_exit
> to properly cleanup the already initialized bits in case
> of a init failure.
> 
> https://bugzilla.redhat.com/show_bug.cgi?id=970551
> 
> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
> ---
>  hw/char/serial-pci.c | 20 ++++++++++++--------
>  1 file changed, 12 insertions(+), 8 deletions(-)
> 
> diff --git a/hw/char/serial-pci.c b/hw/char/serial-pci.c
> index 467c3b4..653064f 100644
> --- a/hw/char/serial-pci.c
> +++ b/hw/char/serial-pci.c
> @@ -48,6 +48,8 @@ typedef struct PCIMultiSerialState {
>      uint8_t      prog_if;
>  } PCIMultiSerialState;
>  
> +static void multi_serial_pci_exit(PCIDevice *dev);
> +
>  static void serial_pci_realize(PCIDevice *dev, Error **errp)
>  {
>      PCISerialState *pci = DO_UPCAST(PCISerialState, dev, dev);
> @@ -89,32 +91,33 @@ static void multi_serial_pci_realize(PCIDevice *dev, Error **errp)
>      PCIMultiSerialState *pci = DO_UPCAST(PCIMultiSerialState, dev, dev);
>      SerialState *s;
>      Error *err = NULL;
> -    int i;
> +    int i, nr_ports = 0;
>  
>      switch (pc->device_id) {
>      case 0x0003:
> -        pci->ports = 2;
> +        nr_ports = 2;
>          break;
>      case 0x0004:
> -        pci->ports = 4;
> +        nr_ports = 4;
>          break;
>      }
> -    assert(pci->ports > 0);
> -    assert(pci->ports <= PCI_SERIAL_MAX_PORTS);
> +    assert(nr_ports > 0);
> +    assert(nr_ports <= PCI_SERIAL_MAX_PORTS);
>  
>      pci->dev.config[PCI_CLASS_PROG] = pci->prog_if;
>      pci->dev.config[PCI_INTERRUPT_PIN] = 0x01;
> -    memory_region_init(&pci->iobar, OBJECT(pci), "multiserial", 8 * pci->ports);
> +    memory_region_init(&pci->iobar, OBJECT(pci), "multiserial", 8 * nr_ports);
>      pci_register_bar(&pci->dev, 0, PCI_BASE_ADDRESS_SPACE_IO, &pci->iobar);
>      pci->irqs = qemu_allocate_irqs(multi_serial_irq_mux, pci,
> -                                   pci->ports);
> +                                   nr_ports);
>  
> -    for (i = 0; i < pci->ports; i++) {
> +    for (i = 0; i < nr_ports; i++) {
>          s = pci->state + i;
>          s->baudbase = 115200;
>          serial_realize_core(s, &err);
>          if (err != NULL) {
>              error_propagate(errp, err);
> +            multi_serial_pci_exit(dev);
>              return;
>          }
>          s->irq = pci->irqs[i];
> @@ -122,6 +125,7 @@ static void multi_serial_pci_realize(PCIDevice *dev, Error **errp)
>          memory_region_init_io(&s->io, OBJECT(pci), &serial_io_ops, s,
>                                pci->name[i], 8);
>          memory_region_add_subregion(&pci->iobar, 8 * i, &s->io);
> +        pci->ports++;
>      }
>  }
>  
> 

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>