Re: [Xen-devel] [BUG] Xen vm kernel crash in get_free_entries.

[Ian Campbell <Ian.Campbell@xxxxxxxxxx>]

On Tue, 2013-11-26 at 15:08 -0500, Konrad Rzeszutek Wilk wrote:
> diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
> index 432db1b..bcbaf0b 100644
> --- a/drivers/block/xen-blkfront.c
> +++ b/drivers/block/xen-blkfront.c
> @@ -2074,7 +2074,7 @@ static int __init xlblk_init(void)
>       if (!xen_domain())
>               return -ENODEV;
>  
> -     if (xen_hvm_domain() && !xen_platform_pci_unplug)
> +     if (xen_err_out())

I think !xen_has_pv_devices() or some such would be a better name.
> diff --git a/include/xen/platform_pci.h b/include/xen/platform_pci.h
> index 438c256..a5bbd0b 100644
> --- a/include/xen/platform_pci.h
> +++ b/include/xen/platform_pci.h
> @@ -47,5 +47,18 @@ static inline int xen_must_unplug_disks(void) {
>  }
>  
>  extern int xen_platform_pci_unplug;
> +static  bool xen_err_out(void)

         ^ stray space, but I think you wanted an inline here anyway?

Or you could move this to arch/x86/xen/platform-pci-unplug.c and then
xen_platform_pci_unplug could be unexported, which seems like a good
thing to do if the logic to using it is as complex as below.

> +{
>  
> +     if (!xen_domain())
> +             return true;
> +
> +     if (xen_hvm_domain()) {
> +             if (xen_platform_pci_unplug & (XEN_UNPLUG_UNNECESSARY | 
> XEN_UNPLUG_NEVER))
> +                     return true;
> +             if (xen_platform_pci_unplug == 0)
> +                     return true;

There are some cases where xen_unplug_emulated_devices doesn't update
xen_platform_pci_unplug, specifically when xen_emul_unplug contains
UNNECESSARY or NEVER. I think the above logic covers that case but it
might be simpler to always set it? At that point on the first if is
necessary?

> +     }
> +     return false;
> +}
>  #endif /* _XEN_PLATFORM_PCI_H */



_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel