From: Murilo Opsfelder Araujo muriloo@linux.ibm.com
stable inclusion from stable-v5.10.124 commit aa9a001efa9ccbb66a22a528bdfce9e825709343 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5L6E7
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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commit 7e415282b41bf0d15c6e0fe268f822d9b083f2f7 upstream.
GCC 12 enhanced -Waddress when comparing array address to null [0], which warns:
drivers/virtio/virtio_pci_common.c: In function ‘vp_del_vqs’: drivers/virtio/virtio_pci_common.c:257:29: warning: the comparison will always evaluate as ‘true’ for the pointer operand in ‘vp_dev->msix_affinity_masks + (sizetype)((long unsigned int)i * 256)’ must not be NULL [-Waddress] 257 | if (vp_dev->msix_affinity_masks[i]) | ^~~~~~
In fact, the verification is comparing the result of a pointer arithmetic, the address "msix_affinity_masks + i", which will always evaluate to true.
Under the hood, free_cpumask_var() calls kfree(), which is safe to pass NULL, not requiring non-null verification. So remove the verification to make compiler happy (happy compiler, happy life).
[0] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102103
Signed-off-by: Murilo Opsfelder Araujo muriloo@linux.ibm.com Message-Id: 20220415023002.49805-1-muriloo@linux.ibm.com Signed-off-by: Michael S. Tsirkin mst@redhat.com Acked-by: Christophe de Dinechin dinechin@redhat.com Cc: Sudip Mukherjee sudipm.mukherjee@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Reviewed-by: Wei Li liwei391@huawei.com --- drivers/virtio/virtio_pci_common.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c index b35bb2d57f62..1e890ef17687 100644 --- a/drivers/virtio/virtio_pci_common.c +++ b/drivers/virtio/virtio_pci_common.c @@ -254,8 +254,7 @@ void vp_del_vqs(struct virtio_device *vdev)
if (vp_dev->msix_affinity_masks) { for (i = 0; i < vp_dev->msix_vectors; i++) - if (vp_dev->msix_affinity_masks[i]) - free_cpumask_var(vp_dev->msix_affinity_masks[i]); + free_cpumask_var(vp_dev->msix_affinity_masks[i]); }
if (vp_dev->msix_enabled) {