| Message ID | 1568450697-16775-1-git-send-email-linux@roeck-us.net (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | vhost: Fix compile time error | expand |
On Sat, Sep 14, 2019 at 01:44:57AM -0700, Guenter Roeck wrote: > Building vhost on 32-bit targets results in the following error. > > drivers/vhost/vhost.c: In function 'translate_desc': > include/linux/compiler.h:549:38: error: > call to '__compiletime_assert_1879' declared with attribute error: > BUILD_BUG_ON failed: sizeof(_s) > sizeof(long) > > Fixes: a89db445fbd7 ("vhost: block speculation of translated descriptors") > Cc: Michael S. Tsirkin <mst@redhat.com> > Cc: Jason Wang <jasowang@redhat.com> > Signed-off-by: Guenter Roeck <linux@roeck-us.net> > --- > drivers/vhost/vhost.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c > index acabf20b069e..102a0c877007 100644 > --- a/drivers/vhost/vhost.c > +++ b/drivers/vhost/vhost.c > @@ -2074,7 +2074,7 @@ static int translate_desc(struct vhost_virtqueue *vq, u64 addr, u32 len, > _iov->iov_base = (void __user *) > ((unsigned long)node->userspace_addr + > array_index_nospec((unsigned long)(addr - node->start), > - node->size)); > + (unsigned long)node->size)); Unfortunately this does not fix the case where size is actually 64 bit, e.g. a single node with VA 0, size 2^32 is how you cover the whole virtual address space. this is not how qemu uses it, but it's valid. I think it's best to just revert the patch for now. > s += size; > addr += size; > ++ret; > -- > 2.7.4
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index acabf20b069e..102a0c877007 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -2074,7 +2074,7 @@ static int translate_desc(struct vhost_virtqueue *vq, u64 addr, u32 len, _iov->iov_base = (void __user *) ((unsigned long)node->userspace_addr + array_index_nospec((unsigned long)(addr - node->start), - node->size)); + (unsigned long)node->size)); s += size; addr += size; ++ret;
Building vhost on 32-bit targets results in the following error. drivers/vhost/vhost.c: In function 'translate_desc': include/linux/compiler.h:549:38: error: call to '__compiletime_assert_1879' declared with attribute error: BUILD_BUG_ON failed: sizeof(_s) > sizeof(long) Fixes: a89db445fbd7 ("vhost: block speculation of translated descriptors") Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net> --- drivers/vhost/vhost.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)