Re: [PATCH] RDMA/restrack: Don't set RESTRACK_DD mark after a failed xa_insert()

[sashiko-bot@kernel.org]

> From: Li RongQing <lirongqing@baidu.com>
> 
> When adding a QP to the restrack xarray, rdma_restrack_add() does:
> 
> 	ret = xa_insert(&rt->xa, res->id, res, GFP_KERNEL);
> 	if (ret)
> 		res->id = 0;
> 
> 	if (qp->qp_type >= IB_QPT_DRIVER)
> 		xa_set_mark(&rt->xa, res->id, RESTRACK_DD);
> 
> The xa_set_mark() call is not guarded by "!ret".  When xa_insert() fails
> (possible on a qp_num collision or memory pressure), res->id is reset to
> 0, yet the mark is still applied to index 0.  If a legitimate QP whose
> qp_num is 0 already occupies that slot - e.g. a normal QP or the SMI QP
> - it is spuriously tagged as driver-private (RESTRACK_DD), and the
> netlink dump path res_get_common_dumpit() then hides it from "rdma res"
> output whenever the caller does not request driver details.
> 
> Only set the mark when the insertion actually succeeded by folding the
> mark into the non-failure branch.
> 
> Fixes: e18fa0bbcedf8 ("RDMA/core: Add an option to display driver-specific QPs in the rdmatool")
> Signed-off-by: Li RongQing <lirongqing@baidu.com>

Sashiko has reviewed this patch and found no issues. It looks great!

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Sashiko AI review · https://sashiko.dev/#/patchset/20260916073042.1746-1-lirongqing@baidu.com?part=1