Re: [PATCH] cxl/hdm: allow zero sized committed decoders

[Vishal Aslot]

Thanks for the quick review, Dave. Yes, forgot to put the commit message. :)
About the copyright message. Should I not be updating the year to 2025 in it?











________________________________________
From: Dave Jiang <dave.jiang@xxxxxxxxx>
Sent: Wednesday, October 1, 2025 4:28 PM
To: Vishal Aslot; Davidlohr Bueso; Jonathan Cameron; Alison Schofield; Vishal Verma; Ira Weiny; Dan Williams; Li Ming; Peter Zijlstra; Dan Carpenter; Zijun Hu; linux-cxl@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Subject: Re: [PATCH] cxl/hdm: allow zero sized committed decoders

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On 10/1/25 1:37 PM, Vishal Aslot wrote:
> Signed-off-by: Vishal Aslot <vaslot@xxxxxxxxxx>

Missing commit log?

> ---
>  drivers/cxl/core/hdm.c | 9 +++++++--
>  1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/cxl/core/hdm.c b/drivers/cxl/core/hdm.c
> index e9e1d555cec6..97a5f27f5b72 100644
> --- a/drivers/cxl/core/hdm.c
> +++ b/drivers/cxl/core/hdm.c
> @@ -1,5 +1,5 @@
>  // SPDX-License-Identifier: GPL-2.0-only
> -/* Copyright(c) 2022 Intel Corporation. All rights reserved. */
> +/* Copyright(c) 2022-2025 Intel Corporation. All rights reserved. */

Stray change?

>  #include <linux/seq_file.h>
>  #include <linux/device.h>
>  #include <linux/delay.h>
> @@ -1050,7 +1050,7 @@ static int init_hdm_decoder(struct cxl_port *port, struct cxl_decoder *cxld,
>                         dev_warn(&port->dev,
>                                  "decoder%d.%d: Committed with zero size\n",
>                                  port->id, cxld->id);

I wonder if we should make this dev_dbg() now that it's a valid case.

> -                       return -ENXIO;
> +                       return -ENOSPC;
>                 }
>                 port->commit_end = cxld->id;
>         } else {
> @@ -1210,6 +1210,11 @@ int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm,
>                 rc = init_hdm_decoder(port, cxld, target_map, hdm, i,
>                                       &dpa_base, info);
>                 if (rc) {
> +                       if (rc == -ENOSPC) {
> +                               put_device(&cxld->dev);

Why put_device()? Should we enumerate this decoder instead of pretend it doesn't exist? essentially only a dev_set_name() and device_add()?

> +                               rc = 0;

Don't think this is needed since the continue will put it at start of the loop where rc gets written by init_hdm_decoder() return value.

> +                               continue;
> +                       }
>                         dev_warn(&port->dev,
>                                  "Failed to initialize decoder%d.%d\n",
>                                  port->id, i);
> --
> 2.34.1