Re: [PATCH] tools/virtio: Test virtual address range detection

["Michael S. Tsirkin" <mst@redhat.com>]

On Tue, Feb 22, 2022 at 11:18:18PM +0000, Matthew Wilcox wrote:
> On Tue, Feb 22, 2022 at 07:58:33AM +0000, David Woodhouse wrote:
> > On Tue, 2022-02-22 at 01:31 -0500, Michael S. Tsirkin wrote:
> > > On Mon, Feb 21, 2022 at 05:18:48PM +0000, David Woodhouse wrote:
> > > > 
> > > > [dwoodhou@i7 virtio]$ sudo ~/virtio_test
> > > > Detected virtual address range 0x1000-0x7ffffffff000
> > > > spurious wakeups: 0x0 started=0x100000 completed=0x100000
> > > > 
> > > > Although in some circumstances I also see a different build failure:
> > > > 
> > > > cc -g -O2 -Werror -Wno-maybe-uninitialized -Wall -I. -I../include/ -I ../../usr/include/ -Wno-pointer-sign -fno-strict-overflow -fno-strict-aliasing -fno-common -MMD -U_FORTIFY_SOURCE -include ../../include/linux/kconfig.h   -c -o vringh_test.o vringh_test.c
> 
> Trying to test this myself ...
> 
> $ cd tools/virtio/
> $ make
> ...
> cc -lpthread  virtio_test.o virtio_ring.o   -o virtio_test
> /usr/bin/ld: virtio_ring.o: in function `spin_lock':
> /home/willy/kernel/folio/tools/virtio/./linux/spinlock.h:16: undefined reference to `pthread_spin_lock'
> 
> So this is not the only problem here?

Could you let me know which system and gcc version have this problem, for inclusion
in the commit log?

> > > > In file included from ./linux/uio.h:3,
> > > >                  from ./linux/../../../include/linux/vringh.h:15,
> > > >                  from ./linux/vringh.h:1,
> > > >                  from vringh_test.c:9:
> > > > ./linux/../../../include/linux/uio.h:10:10: fatal error: linux/mm_types.h: No such file or directory
> > > >    10 | #include <linux/mm_types.h>
> > > >       |          ^~~~~~~~~~~~~~~~~~
> > > > compilation terminated.
> > > > make: *** [<builtin>: vringh_test.o] Error 1
> > > 
> > > Which tree has this build failure? In mine linux/uio.h does not
> > > include linux/mm_types.h.
> > 
> > Strictly it's
> > https://git.infradead.org/users/dwmw2/linux.git/shortlog/refs/heads/xen-evtchn-kernel
> > but I'm sure my part isn't relevant; it's just v5.17-rc5.
> > 
> >  $ git blame include/linux/uio.h | grep mm_types.h
> > d9c19d32d86fa (Matthew Wilcox (Oracle) 2021-10-18 10:39:06 -0400  10) #include <linux/mm_types.h>
> >  $ git describe --tags d9c19d32d86fa
> > v5.16-rc4-37-gd9c19d32d86f
> 
> grr.  Originally, I had this doing a typebusting cast, but hch objected,
> so I had to include mm_types.h.  This should fix it ...
> 
> $ git diff
> diff --git a/tools/virtio/linux/mm_types.h b/tools/virtio/linux/mm_types.h
> new file mode 100644
> index 000000000000..3b0fc9bc5b8f
> --- /dev/null
> +++ b/tools/virtio/linux/mm_types.h
> @@ -0,0 +1,3 @@
> +struct folio {
> +       struct page page;
> +};
> 
> At least, it makes it compile for me.