search for: uninitialized_var

...arch/x86/xen/enlighten.c index e90540a..5ab75e2 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -202,7 +202,7 @@ static void xen_cpuid(unsigned int *ax, unsigned int *bx, static __init void xen_init_cpuid_mask(void) { - unsigned int ax, bx, cx, dx; + unsigned int ax, bx, uninitialized_var(cx), dx; cpuid_leaf1_edx_mask = ~((1 << X86_FEATURE_MCE) | /* disable MCE */ -- 1.6.3.3

...arch/x86/xen/enlighten.c index e90540a..5ab75e2 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -202,7 +202,7 @@ static void xen_cpuid(unsigned int *ax, unsigned int *bx, static __init void xen_init_cpuid_mask(void) { - unsigned int ax, bx, cx, dx; + unsigned int ax, bx, uninitialized_var(cx), dx; cpuid_leaf1_edx_mask = ~((1 << X86_FEATURE_MCE) | /* disable MCE */ -- 1.6.3.3

...arch/x86/xen/enlighten.c index e90540a..5ab75e2 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -202,7 +202,7 @@ static void xen_cpuid(unsigned int *ax, unsigned int *bx, static __init void xen_init_cpuid_mask(void) { - unsigned int ax, bx, cx, dx; + unsigned int ax, bx, uninitialized_var(cx), dx; cpuid_leaf1_edx_mask = ~((1 << X86_FEATURE_MCE) | /* disable MCE */ -- 1.6.3.3

...ng.c b/drivers/virtio/virtio_ring.c index dd35b34..bffec32 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -164,7 +164,8 @@ int virtqueue_add_buf_gfp(struct virtqueue *_vq, gfp_t gfp) { struct vring_virtqueue *vq = to_vvq(_vq); - unsigned int i, avail, head, uninitialized_var(prev); + unsigned int i, avail, uninitialized_var(prev); + int head; START_USE(vq); @@ -174,8 +175,8 @@ int virtqueue_add_buf_gfp(struct virtqueue *_vq, * buffers, then go indirect. FIXME: tune this threshold */ if (vq->indirect && (out + in) > 1 && vq->num_free)...

...ng.c b/drivers/virtio/virtio_ring.c index dd35b34..bffec32 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -164,7 +164,8 @@ int virtqueue_add_buf_gfp(struct virtqueue *_vq, gfp_t gfp) { struct vring_virtqueue *vq = to_vvq(_vq); - unsigned int i, avail, head, uninitialized_var(prev); + unsigned int i, avail, uninitialized_var(prev); + int head; START_USE(vq); @@ -174,8 +175,8 @@ int virtqueue_add_buf_gfp(struct virtqueue *_vq, * buffers, then go indirect. FIXME: tune this threshold */ if (vq->indirect && (out + in) > 1 && vq->num_free)...

...ge); > + > + prev_page = page; > + } > +} > + > /* > * Allocate a zspage for the given size class > */ > static struct page *alloc_zspage(struct size_class *class, gfp_t flags) > { > - int i, error; > + int i; > struct page *first_page = NULL, *uninitialized_var(prev_page); > + struct page *pages[ZS_MAX_PAGES_PER_ZSPAGE]; > > /* > * Allocate individual pages and link them together as: > @@ -1041,43 +1074,23 @@ static struct page *alloc_zspage(struct size_class *class, gfp_t flags) *uninitialized_var(prev_page) in alloc_zspage is not...

...ge); > + > + prev_page = page; > + } > +} > + > /* > * Allocate a zspage for the given size class > */ > static struct page *alloc_zspage(struct size_class *class, gfp_t flags) > { > - int i, error; > + int i; > struct page *first_page = NULL, *uninitialized_var(prev_page); > + struct page *pages[ZS_MAX_PAGES_PER_ZSPAGE]; > > /* > * Allocate individual pages and link them together as: > @@ -1041,43 +1074,23 @@ static struct page *alloc_zspage(struct size_class *class, gfp_t flags) *uninitialized_var(prev_page) in alloc_zspage is not...

...gt;+ } > >+} > >+ > > /* > > * Allocate a zspage for the given size class > > */ > > static struct page *alloc_zspage(struct size_class *class, gfp_t flags) > > { > >- int i, error; > >+ int i; > > struct page *first_page = NULL, *uninitialized_var(prev_page); > >+ struct page *pages[ZS_MAX_PAGES_PER_ZSPAGE]; > > > > /* > > * Allocate individual pages and link them together as: > >@@ -1041,43 +1074,23 @@ static struct page *alloc_zspage(struct size_class *class, gfp_t flags) > > *uninitialized_var(pr...

...#39;t apparent to gcc. >> >> Setting queue = NULL clears the warning. >> >> Signed-off-by: Jeff Mahoney <jeffm at suse.com> > > Which gcc version produces this warning? > I do not seem to see it with gcc 5.3.1. gcc version 4.8.5 (SUSE Linux) > Also - use uninitialized_var then? If it were a fast path, sure, but otherwise the use of uninitialized_var just makes similar issues harder to debug if the code changes. -Jeff >> --- >> >> drivers/virtio/virtio_ring.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> ---...

...#39;t apparent to gcc. >> >> Setting queue = NULL clears the warning. >> >> Signed-off-by: Jeff Mahoney <jeffm at suse.com> > > Which gcc version produces this warning? > I do not seem to see it with gcc 5.3.1. gcc version 4.8.5 (SUSE Linux) > Also - use uninitialized_var then? If it were a fast path, sure, but otherwise the use of uninitialized_var just makes similar issues harder to debug if the code changes. -Jeff >> --- >> >> drivers/virtio/virtio_ring.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> ---...

Hi Krzysztof, freeze(poison) is different from undef today, in the sense that it is an instruction that produces some random, but fixed bit pattern. E.g. today in %x = undef %y = xor %x, %x we can fold %y to undef since each use of %x can independently see some arbitrary (up to the compiler / environment) bit pattern. But in the new proposal, in: %x = freeze(poison) %y = xor

...(+), 1 deletion(-) diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index 984242e..54ffbb0 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -501,7 +501,7 @@ static int get_rx_bufs(struct vhost_virtqueue *vq, int headcount = 0; unsigned d; int r, nlogs = 0; - u32 len; + u32 uninitialized_var(len); while (datalen > 0 && headcount < quota) { if (unlikely(seg >= UIO_MAXIOV)) { -- MST

...(+), 1 deletion(-) diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index 984242e..54ffbb0 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -501,7 +501,7 @@ static int get_rx_bufs(struct vhost_virtqueue *vq, int headcount = 0; unsigned d; int r, nlogs = 0; - u32 len; + u32 uninitialized_var(len); while (datalen > 0 && headcount < quota) { if (unlikely(seg >= UIO_MAXIOV)) { -- MST

...k->ops->peek_len(sock); > + > + return skb_queue_empty(&sk->sk_receive_queue); > +} > + > +static void vhost_net_busy_poll(struct vhost_net *net, > + struct vhost_virtqueue *rvq, > + struct vhost_virtqueue *tvq, > + bool rx) > +{ > + unsigned long uninitialized_var(endtime); > + unsigned long busyloop_timeout; > + struct socket *sock; > + struct vhost_virtqueue *vq = rx ? tvq : rvq; > + > + mutex_lock_nested(&vq->mutex, rx ? VHOST_NET_VQ_TX: VHOST_NET_VQ_RX); > + > + vhost_disable_notify(&net->dev, vq); > + sock = rvq-&gt...

...k->ops->peek_len(sock); > + > + return skb_queue_empty(&sk->sk_receive_queue); > +} > + > +static void vhost_net_busy_poll(struct vhost_net *net, > + struct vhost_virtqueue *rvq, > + struct vhost_virtqueue *tvq, > + bool rx) > +{ > + unsigned long uninitialized_var(endtime); > + unsigned long busyloop_timeout; > + struct socket *sock; > + struct vhost_virtqueue *vq = rx ? tvq : rvq; > + > + mutex_lock_nested(&vq->mutex, rx ? VHOST_NET_VQ_TX: VHOST_NET_VQ_RX); > + > + vhost_disable_notify(&net->dev, vq); > + sock = rvq-&gt...

This fixes the following warning: drivers/virtio/virtio_ring.c:1032:5: warning: ?queue? may be used uninitialized in this function The conditions that govern when queue is set aren't apparent to gcc. Setting queue = NULL clears the warning. Signed-off-by: Jeff Mahoney <jeffm at suse.com> --- drivers/virtio/virtio_ring.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) ---

This fixes the following warning: drivers/virtio/virtio_ring.c:1032:5: warning: ?queue? may be used uninitialized in this function The conditions that govern when queue is set aren't apparent to gcc. Setting queue = NULL clears the warning. Signed-off-by: Jeff Mahoney <jeffm at suse.com> --- drivers/virtio/virtio_ring.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) ---

...984242e..54ffbb0 100644 > > --- a/drivers/vhost/net.c > > +++ b/drivers/vhost/net.c > > @@ -501,7 +501,7 @@ static int get_rx_bufs(struct vhost_virtqueue *vq, > > int headcount = 0; > > unsigned d; > > int r, nlogs = 0; > > - u32 len; > > + u32 uninitialized_var(len); > > > > while (datalen > 0 && headcount < quota) { > > if (unlikely(seg >= UIO_MAXIOV)) { > > Want to merge this with the patch introducing the variable and add a > comment there? Not really. Warnings in bisect are fine I think. -- MST

...984242e..54ffbb0 100644 > > --- a/drivers/vhost/net.c > > +++ b/drivers/vhost/net.c > > @@ -501,7 +501,7 @@ static int get_rx_bufs(struct vhost_virtqueue *vq, > > int headcount = 0; > > unsigned d; > > int r, nlogs = 0; > > - u32 len; > > + u32 uninitialized_var(len); > > > > while (datalen > 0 && headcount < quota) { > > if (unlikely(seg >= UIO_MAXIOV)) { > > Want to merge this with the patch introducing the variable and add a > comment there? Not really. Warnings in bisect are fine I think. -- MST

...+ single_task_running(); > +} > + > +static int vhost_net_tx_get_vq_desc(struct vhost_net *net, > + struct vhost_virtqueue *vq, > + struct iovec iov[], unsigned int iov_size, > + unsigned int *out_num, unsigned int *in_num) > +{ > + unsigned long uninitialized_var(endtime); > + > + if (vq->busyloop_timeout) { > + preempt_disable(); > + endtime = busy_clock() + vq->busyloop_timeout; > + while (vhost_can_busy_poll(vq->dev, endtime) && > + !vhost_vq_more_avail(vq->dev, vq)) > + cpu_relax(); > + preempt_e...