Re: [PATCH v3 01/10] nvme-multipath: add initial support for using libmultipath

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 3 potential issue(s) to consider:
- [Medium] The commit message claims to add an `mpath_disk` pointer to the head structure, but it is entirely missing from the implementation.
- [Low] The patch selects a non-existent Kconfig symbol `LIBMULTIPATH`.
- [Low] The patch references a non-existent header file `<linux/multipath.h>` and instantiates undefined, incomplete structure types.
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commit 733f55d7e9c3919c9123eedece5d53fa4f13cc46
Author: John Garry <john.g.garry@oracle.com>

nvme-multipath: add initial support for using libmultipath

This patch introduces initial structural changes to support libmultipath in
the nvme subsystem. It modifies nvme Kconfig, nvme_ns, and nvme_ns_head
structures to include multipath components.

> Add initial support, as follows:
> - Add mpath_head_template
> - Add mpath_device in nvme_ns
> - Add mpath_disk pointer to head structure

[Severity: Medium]
The commit message states that an mpath_disk pointer is being added to the
head structure, but the actual implementation below adds a struct mpath_head
by value instead. Is the commit message stale, or was this pointer omitted
by mistake?

> diff --git a/drivers/nvme/host/Kconfig b/drivers/nvme/host/Kconfig
> index 31974c7dd20c9..1b3f76e781bad 100644
> --- a/drivers/nvme/host/Kconfig
> +++ b/drivers/nvme/host/Kconfig
> @@ -1,6 +1,7 @@
>  # SPDX-License-Identifier: GPL-2.0-only
>  config NVME_CORE
>  	tristate
> +	select LIBMULTIPATH

[Severity: Low]
Does the LIBMULTIPATH Kconfig symbol exist in the tree? Selecting a
non-existent symbol here will result in Kconfig unmet dependency warnings.

> diff --git a/drivers/nvme/host/multipath.c b/drivers/nvme/host/multipath.c
> index 9b9a657fa330f..14947736744a5 100644
> --- a/drivers/nvme/host/multipath.c
> +++ b/drivers/nvme/host/multipath.c

[ ... ]

> @@ -1496,3 +1496,7 @@ void nvme_mpath_uninit(struct nvme_ctrl *ctrl)
>  	ctrl->ana_log_buf = NULL;
>  	ctrl->ana_log_size = 0;
>  }
> +
> +__maybe_unused
> +static const struct mpath_head_template mpdt = {
> +};

[Severity: Low]
Does this compile? The struct mpath_head_template type does not appear to be
defined anywhere.

> diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
> index 824651cc898db..3e023948015ac 100644
> --- a/drivers/nvme/host/nvme.h
> +++ b/drivers/nvme/host/nvme.h
> @@ -13,6 +13,7 @@
>  #include <linux/blk-mq.h>
>  #include <linux/sed-opal.h>
>  #include <linux/fault-inject.h>
> +#include <linux/multipath.h>

[Severity: Low]
Is linux/multipath.h present in the tree? Including a missing header will
cause build failures.

[ ... ]

> @@ -560,6 +561,8 @@ struct nvme_ns_head {
>  
>  	u16			nr_plids;
>  	u16			*plids;
> +
> +	struct mpath_head	mpath_head;
>  #ifdef CONFIG_NVME_MULTIPATH
>  	struct bio_list		requeue_list;
>  	spinlock_t		requeue_lock;
> @@ -590,6 +593,7 @@ enum nvme_ns_features {
>  };
>  
>  struct nvme_ns {
> +	struct mpath_device mpath_device;
>  	struct list_head list;

[Severity: Low]
Since linux/multipath.h does not seem to exist, these embed undefined
structures (struct mpath_head and struct mpath_device) directly by value,
which will result in incomplete type errors during compilation.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260703103204.3724406-1-john.g.garry@oracle.com?part=1