Re: [PATCH v1 15/15] RDMA/xsc: add RDMA counters and sysfs

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] RDMA/xsc: cast counter pointers to __be64 * in xsc_ib_get_hw_stats()
--

commit 9a3d01fb1064f09ed97cbe2bb05c71e3ed77198c
Author: Xin Tian <tianx@yunsilicon.com>

RDMA/xsc: add RDMA counters and sysfs

This commit adds the RDMA hw_stats callbacks to query per-function and
card-global statistics from firmware, and exposes the hca_type and hw_rev
sysfs attributes on the ib_device class device.

> diff --git a/drivers/infiniband/hw/xsc/counters.c b/drivers/infiniband/hw/xsc/counters.c
> new file mode 100644
> index 0000000000000..c29a5bf8007f1
> --- /dev/null
> +++ b/drivers/infiniband/hw/xsc/counters.c
> @@ -0,0 +1,134 @@

[ ... ]

> +int xsc_ib_get_hw_stats(struct ib_device *ib_dev, struct rdma_hw_stats *stats,
> +		       u32 port_num, int index)
> +{
> +	struct xsc_core_device *xdev = to_xdev(ib_dev)->xdev;
> +	struct xsc_hw_stats_rdma stats_rdma;
> +	u8 *hw_stats;
> +	int ret;
> +	int i;
> +
> +	ret = xsc_ib_query_hw_stats_rdma(xdev, &stats_rdma);
> +	if (ret)
> +		return ret;
> +
> +	hw_stats = (u8 *)&stats_rdma.stats.pf_stats;
> +
> +	for (i = 0; i < stats->num_counters && i < XSC_NUM_PF_STATS; i++)
> +		stats->value[i] =
> +			be64_to_cpu(*(u64 *)(hw_stats + (uintptr_t)stats->descs[i].priv));
> +
> +	if (stats->num_counters > XSC_NUM_PF_STATS) {
> +		struct xsc_hw_global_stats_mbox_in gin = {};
> +		struct xsc_hw_global_stats_mbox_out gout = {};
> +
> +		gin.hdr.opcode = cpu_to_be16(XSC_CMD_OP_QUERY_HW_GLOBAL_STATS);
> +		ret = xsc_cmd_exec(xdev, &gin, sizeof(gin), &gout, sizeof(gout));
> +		if (ret || gout.hdr.status)
> +			return -EIO;
> +
> +		hw_stats = (u8 *)&gout.hw_stats;
> +		for (i = XSC_NUM_PF_STATS; i < stats->num_counters; i++)
> +			stats->value[i] = be64_to_cpu(
> +				*(u64 *)(hw_stats + (uintptr_t)stats->descs[i].priv));
> +	}

[Severity: Low]
In xsc_ib_get_hw_stats(), both loops cast the counter field address to
u64 * before passing the dereferenced value to be64_to_cpu().

In drivers/net/ethernet/yunsilicon/xsc/common/xsc_cmd.h, the counter
fields in struct xsc_hw_stats_rdma_pf and struct xsc_hw_global_stats_rdma
are declared as __be64. Passing a host-typed u64 expression to
be64_to_cpu() triggers Sparse endianness warnings (cast to restricted
__be64) when building with C=1.

Should these casts in xsc_ib_get_hw_stats() use (__be64 *) instead of
(u64 *)?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261104155650.37053-1-tianx@yunsilicon.com?part=15