[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-devel] [PATCH] stubdom/libxc: Fix build of unsafe decompressors

On Fri, 2014-03-14 at 11:16 +0000, Andrew Cooper wrote:
> c/s b683d68c386 changed the packing attribute on struct lzma_header.

Since this is third party code (which presumably we want to keep mostly
in sync) was this a good idea? Perhaps we should just revert that

>   libxc
> includes the Xen decompression .c, (for stubdoms only) but without access to
> the Xen header files.
> Fix in the main header file for any potential change in Xen, rather than in
> for just lzma alone.

This has the disadvantage that any external compression we import in the
future had better not define it's own __packed macro.

Also __packed is not validly namespaced for userspace where it is
reserved for either POSIX or the compiler (can't be bother to check
which). Maybe we already get this wrong in other places but given the is
change to 3rd party code I'm even more strongly inclined to go with the
revert option.


> Reported-by: Sander Eikelenboom <linux@xxxxxxxxxxxxxx>
> Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
> CC: Keir Fraser <keir@xxxxxxx>
> CC: Jan Beulich <JBeulich@xxxxxxxx>
> CC: Ian Campbell <Ian.Campbell@xxxxxxxxxx>
> CC: Ian Jackson <Ian.Jackson@xxxxxxxxxxxxx>
> ---
>  tools/libxc/xc_dom_decompress_unsafe.h |    2 ++
>  1 file changed, 2 insertions(+)
> diff --git a/tools/libxc/xc_dom_decompress_unsafe.h 
> b/tools/libxc/xc_dom_decompress_unsafe.h
> index 64f6886..66124a8 100644
> --- a/tools/libxc/xc_dom_decompress_unsafe.h
> +++ b/tools/libxc/xc_dom_decompress_unsafe.h
> @@ -1,5 +1,7 @@
>  #include "xc_dom.h"
> +#define __packed __attribute__((packed))
> +
>  typedef int decompress_fn(unsigned char *inbuf, unsigned int len,
>                            int (*fill)(void*, unsigned int),
>                            int (*flush)(void*, unsigned int),

Xen-devel mailing list



Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.