Re: [PATCH 5/5] kexec/xen: directly load images images into Xen

Daniel Kiper
2013-04-17T12:56:14Z

On Tue, Apr 09, 2013 at 11:20:36PM +0200, Daniel Kiper wrote:
> On Mon, Apr 08, 2013 at 08:06:54PM +0100, David Vrabel wrote:
> > From: David Vrabel <david.vrabel@citrix.com>
> >
> > Xen 4.3 has an improvided kexec hypercall ABI that allows images to be
> > loaded and executed without any kernel involvement. Use the API
> > provided by libxc to load images when running in a Xen guest.
> >
> > Support for loading images via the kexec_load syscall in non-upstream
> > ("classic") Xen kernels is no longer supported.
> >
> > Signed-off-by: David Vrabel <david.vrabel@citrix.com>
>
> [...]
>
> > diff --git a/kexec/kexec-xen.c b/kexec/kexec-xen.c
>
> [...]
>
> > +int xen_kexec_load(uint64_t entry,
> > + uint32_t nr_segments, struct kexec_segment *segments,
> > + uint64_t kexec_flags)
> > +{
> > + xc_interface *xch;
> > + xc_hypercall_buffer_array_t *array = NULL;
> > + uint8_t type;
> > + uint8_t arch;
> > + xen_kexec_segment_t *xen_segs;
> > + int s;
> > + int ret = -1;
> > +
> > + xch = xc_interface_open(NULL, NULL, 0);
> > + if (!xch)
> > + return -1;
> > +
> > + xen_segs = calloc(nr_segments, sizeof(*xen_segs));
> > + if (!xen_segs)
> > + goto out;
> > +
> > + array = xc_hypercall_buffer_array_create(xch, nr_segments);
> > + if (array == NULL)
> > + goto out;
> > +
> > + for (s = 0; s < nr_segments; s++) {
> > + DECLARE_HYPERCALL_BUFFER(void, seg_buf);
> > +
> > + seg_buf = xc_hypercall_buffer_array_alloc(xch, array, s,
> > + seg_buf, segments[s].bufsz);
> > + if (seg_buf == NULL)
> > + goto out;
> > + memcpy(seg_buf, segments[s].buf, segments[s].bufsz);
> > +
> > + set_xen_guest_handle(xen_segs[s].buf, seg_buf);
> > + xen_segs[s].buf_size = segments[s].bufsz;
> > + xen_segs[s].dest_maddr = (uint64_t)segments[s].mem;
> > + xen_segs[s].dest_size = segments[s].memsz;
> > + }
> > +
> > + type = kexec_flags & KEXEC_TYPE_CRASH;
> > + arch = (kexec_flags >> 16) & 0xffff;
>
> arch = (kexec_flags & KEXEC_ARCH_MASK) >> 16;

What is wrong with this line?
Why did not you applied it?

Daniel