Re: [PATCH] misc/xenmicrocode: Upload /lib/firmware/<some blob> to the hypervisor

[Boris Ostrovsky <boris.ostrovsky@oracle.com>]

On 01/27/2015 03:11 PM, Luis R. Rodriguez wrote:
> +    fbuf = mmap(0, len, PROT_READ, MAP_PRIVATE, fd, 0);
> +
> +    if ((xc_handle = xc_interface_open(0,0,0)) == 0)
> +    {
> +        fprintf(stderr, "Error opening xc interface: %d (%s)\n",
> +                errno, strerror(errno));
> +        return 1;
> +    }
> +
> +    if (fbuf == MAP_FAILED)
> +    {
> +        printf("Could not map: error: %d(%s)\n", errno,
> +               strerror(errno));
> +        return errno;
> +    }

Shouldn't this 'if' block directly follow the mmap()?

> +
> +    uc = xc_hypercall_buffer_alloc(xc_handle, uc, len);
> +    memcpy(uc, fbuf, len);
> +
> +    set_xen_guest_handle(op.u.microcode.data, uc);
> +    op.cmd = XENPF_microcode_update;
> +    op.interface_version = XENPF_INTERFACE_VERSION;
> +    op.u.microcode.length = len;
> +    xc_platform_op(xc_handle, &op);
> +
> +    xc_hypercall_buffer_free(xc_handle, uc);
> +    xc_interface_close(xc_handle);
> +
> +    if (munmap(fbuf, len))
> +    {
> +        printf("Could not unmap: %d(%s)\n", errno, strerror(errno));
> +        return errno;
> +    }
> +
> +    close(fd);

Given that you never close the file on errors this is not really 
necessary. Or you should close it on errors for consistency.


-boris