Re: [Qemu-devel] [PATCH QEMU-XEN v4 3/9] xen: Switch to libxengnttab interface for compat shims.

[Ian Campbell]

On Fri, 2015-10-23 at 12:06 +0100, Stefano Stabellini wrote:
> On Wed, 21 Oct 2015, Ian Campbell wrote:
> > In Xen 4.7 we are refactoring parts libxenctrl into a number of
> > separate libraries which will provide backward and forward API and ABI
> > compatiblity.
> > 
> > One such library will be libxengnttab which provides access to grant
> > tables.
> > 
> > In preparation for this switch the compatibility layer in xen_common.h
> > (which support building with older versions of Xen) to use what will
> > be the new library API. This means that the gnttab shim will disappear
> > for versions of Xen which include libxengnttab.
> > 
> > To simplify things for the <= 4.0.0 support we wrap the int fd in a
> > malloc(sizeof int) such that the handle is always a pointer. This
> > leads to less typedef headaches and the need for
> > XC_HANDLER_INITIAL_VALUE etc for these interfaces.
> > 
> > Build tested with 4.0 and 4.5.
> > 
> > Note that this patch does not add any support for actually using
> > libxengnttab, it just adjusts the existing shims.
> > 
> > Signed-off-by: Ian Campbell <address@hidden>
> 
> The patch looks OK but doesn't apply cleanly to master, please rebase.
> After fixing it up, it fails my 4.0 build test (I probably made a
> mistake).

It was based on:

commit 816609b2841297925a223ec377c336360e044ee5
Author: Gerd Hoffmann <address@hidden>
Date:   Tue Jun 9 21:08:47 2015 +0200

    spice-display: fix segfault in qemu_spice_create_update
    
Ah, I'm pointing at our xenbits qemu upstream tree (master branch, not even
upstream-tested) not the qemu.org one. I'll update to base on proper
mainline for v5 next time.

(I thought things were awfully quite on the incoming patches front when I
ran git remote update!)