Re: [PATCH] vdpa/mlx5: Avoid warnings about shifts on 32-bit platforms
From: Nathan Chancellor <hidden>
Date: 2020-08-21 23:20:42
Also in:
lkml
On Fri, Aug 21, 2020 at 04:13:19PM -0700, Randy Dunlap wrote:
On 8/21/20 3:50 PM, Nathan Chancellor wrote:quoted
Clang warns several times when building for 32-bit ARM along the lines of: drivers/vdpa/mlx5/net/mlx5_vnet.c:1462:31: warning: shift count >= width of type [-Wshift-count-overflow] ndev->mvdev.mlx_features |= BIT(VIRTIO_F_VERSION_1); ^~~~~~~~~~~~~~~~~~~~~~~ This is related to the BIT macro, which uses an unsigned long literal, which is 32-bit on ARM so having a shift equal to or larger than 32 will cause this warning, such as the above, where VIRTIO_F_VERSION_1 is 32. To avoid this, use BIT_ULL, which will be an unsigned long long. This matches the size of the features field throughout this driver, which is u64 so there should be no functional change. Fixes: 1a86b377aa21 ("vdpa/mlx5: Add VDPA driver for supported mlx5 devices") Link: https://github.com/ClangBuiltLinux/linux/issues/1140 Signed-off-by: Nathan Chancellor <redacted>Reported-by: Randy Dunlap <redacted> on 2020-AUG-10 for i386: https://lore.kernel.org/linux-next/5a7a0e6d-842a-78f6-aeac-c5b4c27b7186@infradead.org/ (local) :(
Sorry, I saw this in my own build tests and was not aware of the previous report since I have not really been paying attention to the mailing lists as of late :( Should I need to do a v2, I will be sure to include that tag; otherwise, it would be great if it could be picked up along with the below.
Acked-by: Randy Dunlap <redacted> # build-tested
Thank you for testing!
Thanks.quoted
--- drivers/vdpa/mlx5/net/mlx5_vnet.c | 50 +++++++++++++++---------------- 1 file changed, 25 insertions(+), 25 deletions(-)diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c index 9df69d5efe8c..70676a6d1691 100644 --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c@@ -16,19 +16,19 @@ #define to_mvdev(__vdev) container_of((__vdev), struct mlx5_vdpa_dev, vdev) #define VALID_FEATURES_MASK \ - (BIT(VIRTIO_NET_F_CSUM) | BIT(VIRTIO_NET_F_GUEST_CSUM) | \ - BIT(VIRTIO_NET_F_CTRL_GUEST_OFFLOADS) | BIT(VIRTIO_NET_F_MTU) | BIT(VIRTIO_NET_F_MAC) | \ - BIT(VIRTIO_NET_F_GUEST_TSO4) | BIT(VIRTIO_NET_F_GUEST_TSO6) | \ - BIT(VIRTIO_NET_F_GUEST_ECN) | BIT(VIRTIO_NET_F_GUEST_UFO) | BIT(VIRTIO_NET_F_HOST_TSO4) | \ - BIT(VIRTIO_NET_F_HOST_TSO6) | BIT(VIRTIO_NET_F_HOST_ECN) | BIT(VIRTIO_NET_F_HOST_UFO) | \ - BIT(VIRTIO_NET_F_MRG_RXBUF) | BIT(VIRTIO_NET_F_STATUS) | BIT(VIRTIO_NET_F_CTRL_VQ) | \ - BIT(VIRTIO_NET_F_CTRL_RX) | BIT(VIRTIO_NET_F_CTRL_VLAN) | \ - BIT(VIRTIO_NET_F_CTRL_RX_EXTRA) | BIT(VIRTIO_NET_F_GUEST_ANNOUNCE) | \ - BIT(VIRTIO_NET_F_MQ) | BIT(VIRTIO_NET_F_CTRL_MAC_ADDR) | BIT(VIRTIO_NET_F_HASH_REPORT) | \ - BIT(VIRTIO_NET_F_RSS) | BIT(VIRTIO_NET_F_RSC_EXT) | BIT(VIRTIO_NET_F_STANDBY) | \ - BIT(VIRTIO_NET_F_SPEED_DUPLEX) | BIT(VIRTIO_F_NOTIFY_ON_EMPTY) | \ - BIT(VIRTIO_F_ANY_LAYOUT) | BIT(VIRTIO_F_VERSION_1) | BIT(VIRTIO_F_ACCESS_PLATFORM) | \ - BIT(VIRTIO_F_RING_PACKED) | BIT(VIRTIO_F_ORDER_PLATFORM) | BIT(VIRTIO_F_SR_IOV)) + (BIT_ULL(VIRTIO_NET_F_CSUM) | BIT_ULL(VIRTIO_NET_F_GUEST_CSUM) | \ + BIT_ULL(VIRTIO_NET_F_CTRL_GUEST_OFFLOADS) | BIT_ULL(VIRTIO_NET_F_MTU) | BIT_ULL(VIRTIO_NET_F_MAC) | \ + BIT_ULL(VIRTIO_NET_F_GUEST_TSO4) | BIT_ULL(VIRTIO_NET_F_GUEST_TSO6) | \ + BIT_ULL(VIRTIO_NET_F_GUEST_ECN) | BIT_ULL(VIRTIO_NET_F_GUEST_UFO) | BIT_ULL(VIRTIO_NET_F_HOST_TSO4) | \ + BIT_ULL(VIRTIO_NET_F_HOST_TSO6) | BIT_ULL(VIRTIO_NET_F_HOST_ECN) | BIT_ULL(VIRTIO_NET_F_HOST_UFO) | \ + BIT_ULL(VIRTIO_NET_F_MRG_RXBUF) | BIT_ULL(VIRTIO_NET_F_STATUS) | BIT_ULL(VIRTIO_NET_F_CTRL_VQ) | \ + BIT_ULL(VIRTIO_NET_F_CTRL_RX) | BIT_ULL(VIRTIO_NET_F_CTRL_VLAN) | \ + BIT_ULL(VIRTIO_NET_F_CTRL_RX_EXTRA) | BIT_ULL(VIRTIO_NET_F_GUEST_ANNOUNCE) | \ + BIT_ULL(VIRTIO_NET_F_MQ) | BIT_ULL(VIRTIO_NET_F_CTRL_MAC_ADDR) | BIT_ULL(VIRTIO_NET_F_HASH_REPORT) | \ + BIT_ULL(VIRTIO_NET_F_RSS) | BIT_ULL(VIRTIO_NET_F_RSC_EXT) | BIT_ULL(VIRTIO_NET_F_STANDBY) | \ + BIT_ULL(VIRTIO_NET_F_SPEED_DUPLEX) | BIT_ULL(VIRTIO_F_NOTIFY_ON_EMPTY) | \ + BIT_ULL(VIRTIO_F_ANY_LAYOUT) | BIT_ULL(VIRTIO_F_VERSION_1) | BIT_ULL(VIRTIO_F_ACCESS_PLATFORM) | \ + BIT_ULL(VIRTIO_F_RING_PACKED) | BIT_ULL(VIRTIO_F_ORDER_PLATFORM) | BIT_ULL(VIRTIO_F_SR_IOV)) #define VALID_STATUS_MASK \ (VIRTIO_CONFIG_S_ACKNOWLEDGE | VIRTIO_CONFIG_S_DRIVER | VIRTIO_CONFIG_S_DRIVER_OK | \@@ -149,7 +149,7 @@ static bool mlx5_vdpa_debug; #define MLX5_LOG_VIO_FLAG(_feature) \ do { \ - if (features & BIT(_feature)) \ + if (features & BIT_ULL(_feature)) \ mlx5_vdpa_info(mvdev, "%s\n", #_feature); \ } while (0)@@ -750,10 +750,10 @@ static bool vq_is_tx(u16 idx) static u16 get_features_12_3(u64 features) { - return (!!(features & BIT(VIRTIO_NET_F_HOST_TSO4)) << 9) | - (!!(features & BIT(VIRTIO_NET_F_HOST_TSO6)) << 8) | - (!!(features & BIT(VIRTIO_NET_F_CSUM)) << 7) | - (!!(features & BIT(VIRTIO_NET_F_GUEST_CSUM)) << 6); + return (!!(features & BIT_ULL(VIRTIO_NET_F_HOST_TSO4)) << 9) | + (!!(features & BIT_ULL(VIRTIO_NET_F_HOST_TSO6)) << 8) | + (!!(features & BIT_ULL(VIRTIO_NET_F_CSUM)) << 7) | + (!!(features & BIT_ULL(VIRTIO_NET_F_GUEST_CSUM)) << 6); } static int create_virtqueue(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtqueue *mvq)@@ -1439,13 +1439,13 @@ static u64 mlx_to_vritio_features(u16 dev_features) u64 result = 0; if (dev_features & MLX5_VIRTIO_NET_F_GUEST_CSUM) - result |= BIT(VIRTIO_NET_F_GUEST_CSUM); + result |= BIT_ULL(VIRTIO_NET_F_GUEST_CSUM); if (dev_features & MLX5_VIRTIO_NET_F_CSUM) - result |= BIT(VIRTIO_NET_F_CSUM); + result |= BIT_ULL(VIRTIO_NET_F_CSUM); if (dev_features & MLX5_VIRTIO_NET_F_HOST_TSO6) - result |= BIT(VIRTIO_NET_F_HOST_TSO6); + result |= BIT_ULL(VIRTIO_NET_F_HOST_TSO6); if (dev_features & MLX5_VIRTIO_NET_F_HOST_TSO4) - result |= BIT(VIRTIO_NET_F_HOST_TSO4); + result |= BIT_ULL(VIRTIO_NET_F_HOST_TSO4); return result; }@@ -1459,15 +1459,15 @@ static u64 mlx5_vdpa_get_features(struct vdpa_device *vdev) dev_features = MLX5_CAP_DEV_VDPA_EMULATION(mvdev->mdev, device_features_bits_mask); ndev->mvdev.mlx_features = mlx_to_vritio_features(dev_features); if (MLX5_CAP_DEV_VDPA_EMULATION(mvdev->mdev, virtio_version_1_0)) - ndev->mvdev.mlx_features |= BIT(VIRTIO_F_VERSION_1); - ndev->mvdev.mlx_features |= BIT(VIRTIO_F_ACCESS_PLATFORM); + ndev->mvdev.mlx_features |= BIT_ULL(VIRTIO_F_VERSION_1); + ndev->mvdev.mlx_features |= BIT_ULL(VIRTIO_F_ACCESS_PLATFORM); print_features(mvdev, ndev->mvdev.mlx_features, false); return ndev->mvdev.mlx_features; } static int verify_min_features(struct mlx5_vdpa_dev *mvdev, u64 features) { - if (!(features & BIT(VIRTIO_F_ACCESS_PLATFORM))) + if (!(features & BIT_ULL(VIRTIO_F_ACCESS_PLATFORM))) return -EOPNOTSUPP; return 0;base-commit: 8a7c3213db068135e816a6a517157de6443290d6-- ~Randy -- You received this message because you are subscribed to the Google Groups "Clang Built Linux" group. To unsubscribe from this group and stop receiving emails from it, send an email to clang-built-linux+unsubscribe@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/clang-built-linux/1975c0a0-c19a-c91e-dc10-2918061cc4e7%40infradead.org.
_______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization