From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: Re: [PATCH RESEND] virtio: Fix typecast of pointer in vring_init() Date: Sun, 5 Jul 2015 14:59:54 +0200 Message-ID: <20150705145917-mutt-send-email-mst@redhat.com> References: <1435821682-1809-1-git-send-email-thuth@redhat.com> <20150705124937-mutt-send-email-mst@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Content-Disposition: inline In-Reply-To: <20150705124937-mutt-send-email-mst-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> Sender: linux-api-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Thomas Huth Cc: virtualization-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-api@vger.kernel.org On Sun, Jul 05, 2015 at 12:58:53PM +0200, Michael S. Tsirkin wrote: > On Thu, Jul 02, 2015 at 09:21:22AM +0200, Thomas Huth wrote: > > The virtio_ring.h header is used in userspace programs (ie. QEMU), > > too. Here we can not assume that sizeof(pointer) is the same as > > sizeof(long), e.g. when compiling for Windows, so the typecast in > > vring_init() should be done with (uintptr_t) instead of (unsigned l= ong). > >=20 > > Signed-off-by: Thomas Huth >=20 > This seems to break some userspace too: >=20 > INSTALL usr/include/linux/ (413 files) > CHECK usr/include/linux/ (413 files) > HOSTCC Documentation/accounting/getdelays > HOSTCC Documentation/connector/ucon > HOSTCC Documentation/mic/mpssd/mpssd.o > In file included from Documentation/mic/mpssd/mpssd.c:36:0: > ./usr/include/linux/virtio_ring.h: In function =E2=80=98vring_init=E2= =80=99: > ./usr/include/linux/virtio_ring.h:146:24: error: =E2=80=98uintptr_t=E2= =80=99 undeclared > (first use in this function) > vr->used =3D (void *)(((uintptr_t)&vr->avail->ring[num] + > sizeof(__virtio16) > ^ > ./usr/include/linux/virtio_ring.h:146:24: note: each undeclared > identifier is reported only once for each function it appears in > scripts/Makefile.host:108: recipe for target > 'Documentation/mic/mpssd/mpssd.o' failed > make[3]: *** [Documentation/mic/mpssd/mpssd.o] Error 1 > scripts/Makefile.build:403: recipe for target 'Documentation/mic/mpss= d' > failed > make[2]: *** [Documentation/mic/mpssd] Error 2 > scripts/Makefile.build:403: recipe for target 'Documentation/mic' fai= led > make[1]: *** [Documentation/mic] Error 2 >=20 >=20 > E.g. fuse.h has this code: > #ifdef __KERNEL__ > #include > #else > #include > #endif >=20 > Maybe we need something similar. The following seems to help. Does it help the windows build? --- include/uapi/linux/virtio_ring.h | 3 +++ 1 file changed, 3 insertions(+) diff --git a/include/uapi/linux/virtio_ring.h b/include/uapi/linux/virt= io_ring.h index 8682551..c072959 100644 --- a/include/uapi/linux/virtio_ring.h +++ b/include/uapi/linux/virtio_ring.h @@ -31,6 +31,9 @@ * SUCH DAMAGE. * * Copyright Rusty Russell IBM Corporation 2007. */ +#ifndef __KERNEL__ +#include +#endif #include #include =20 --=20 MST