Re: [Qemu-devel] [PATCH v3 07/42] sdhci: refactor common sysbus/pci unrealize() into sdhci_unrealizefn()

[Fam Zheng <famz@redhat.com>]

On Fri, 12/29 14:48, Philippe Mathieu-Daudé wrote:
> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> ---
>  hw/sd/sdhci.c | 19 ++++++++++++++++---
>  1 file changed, 16 insertions(+), 3 deletions(-)
> 
> diff --git a/hw/sd/sdhci.c b/hw/sd/sdhci.c
> index ad5853d527..06a1ec6f91 100644
> --- a/hw/sd/sdhci.c
> +++ b/hw/sd/sdhci.c
> @@ -31,6 +31,7 @@
>  #include "qemu/bitops.h"
>  #include "hw/sd/sdhci.h"
>  #include "sdhci-internal.h"
> +#include "qapi/error.h"
>  #include "qemu/log.h"
>  
>  /* host controller debug messages */
> @@ -1203,15 +1204,17 @@ static void sdhci_realizefn(SDHCIState *s, Error **errp)
>                            SDHC_REGISTERS_MAP_SIZE);
>  }
>  
> +static void sdhci_unrealizefn(SDHCIState *s, Error **errp)
> +{
> +    g_free(s->fifo_buffer);

Set s->fifo_buffer to NULL to avoid double-free and/or use-after-free?
Especially since you call this from both the ->exit and the ->unrealize
callbacks.

> +}
> +
>  static void sdhci_uninitfn(SDHCIState *s)
>  {
>      timer_del(s->insert_timer);
>      timer_free(s->insert_timer);
>      timer_del(s->transfer_timer);
>      timer_free(s->transfer_timer);
> -
> -    g_free(s->fifo_buffer);
> -    s->fifo_buffer = NULL;
>  }
>  
>  static bool sdhci_pending_insert_vmstate_needed(void *opaque)
> @@ -1312,6 +1315,8 @@ static void sdhci_pci_realize(PCIDevice *dev, Error **errp)
>  static void sdhci_pci_exit(PCIDevice *dev)
>  {
>      SDHCIState *s = PCI_SDHCI(dev);
> +
> +    sdhci_unrealizefn(s, &error_abort);
>      sdhci_uninitfn(s);
>  }
>  
> @@ -1365,11 +1370,19 @@ static void sdhci_sysbus_realize(DeviceState *dev, Error ** errp)
>      sysbus_init_mmio(sbd, &s->iomem);
>  }
>  
> +static void sdhci_sysbus_unrealize(DeviceState *dev, Error **errp)
> +{
> +    SDHCIState *s = SYSBUS_SDHCI(dev);
> +
> +    sdhci_unrealizefn(s, errp);
> +}
> +
>  static void sdhci_sysbus_class_init(ObjectClass *klass, void *data)
>  {
>      DeviceClass *dc = DEVICE_CLASS(klass);
>  
>      dc->realize = sdhci_sysbus_realize;
> +    dc->unrealize = sdhci_sysbus_unrealize;
>  
>      sdhci_class_init(klass, data);
>  }
> -- 
> 2.15.1
> 
> 

Fam