linux-kernel - Re: [PATCH v2 2/2] EDAC/mc_sysfs: Increase legacy channel support to 16

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250818213651.GIaKOc88InL4iy-SGM@fat_crate.local>
Date: Mon, 18 Aug 2025 23:36:51 +0200
From: Borislav Petkov <bp@...en8.de>
To: Avadhut Naik <avadhut.naik@....com>
Cc: linux-edac@...r.kernel.org, yazen.ghannam@....com,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH v2 2/2] EDAC/mc_sysfs: Increase legacy channel support to
 16

On Thu, Aug 07, 2025 at 08:14:54PM +0000, Avadhut Naik wrote:
> Newer AMD systems can support up to 16 channels per EDAC "mc" device.
> These are detected by the EDAC module running on the device, and the
> current EDAC interface is appropriately enumerated.
> 
> The legacy EDAC sysfs interface however, provides device attributes for
> channels 0 through 11 only. Consequently, the last four channels, 12
> through 15, will not be enumerated and will not be visible through the
> legacy sysfs interface.
> 
> Add additional device attributes to ensure that all 16 channels, if
> present, are enumerated by and visible through the legacy EDAC sysfs
> interface.
> 
> Signed-off-by: Avadhut Naik <avadhut.naik@....com>
> ---
>  drivers/edac/edac_mc_sysfs.c | 24 ++++++++++++++++++++++++
>  1 file changed, 24 insertions(+)
> 
> diff --git a/drivers/edac/edac_mc_sysfs.c b/drivers/edac/edac_mc_sysfs.c
> index 0f338adf7d93..8689631f1905 100644
> --- a/drivers/edac/edac_mc_sysfs.c
> +++ b/drivers/edac/edac_mc_sysfs.c
> @@ -305,6 +305,14 @@ DEVICE_CHANNEL(ch10_dimm_label, S_IRUGO | S_IWUSR,
>  	channel_dimm_label_show, channel_dimm_label_store, 10);
>  DEVICE_CHANNEL(ch11_dimm_label, S_IRUGO | S_IWUSR,
>  	channel_dimm_label_show, channel_dimm_label_store, 11);
> +DEVICE_CHANNEL(ch12_dimm_label, S_IRUGO | S_IWUSR,
> +	channel_dimm_label_show, channel_dimm_label_store, 12);
> +DEVICE_CHANNEL(ch13_dimm_label, S_IRUGO | S_IWUSR,
> +	channel_dimm_label_show, channel_dimm_label_store, 13);
> +DEVICE_CHANNEL(ch14_dimm_label, S_IRUGO | S_IWUSR,
> +	channel_dimm_label_show, channel_dimm_label_store, 14);
> +DEVICE_CHANNEL(ch15_dimm_label, S_IRUGO | S_IWUSR,
> +	channel_dimm_label_show, channel_dimm_label_store, 15);
>  
>  /* Total possible dynamic DIMM Label attribute file table */
>  static struct attribute *dynamic_csrow_dimm_attr[] = {
> @@ -320,6 +328,10 @@ static struct attribute *dynamic_csrow_dimm_attr[] = {
>  	&dev_attr_legacy_ch9_dimm_label.attr.attr,
>  	&dev_attr_legacy_ch10_dimm_label.attr.attr,
>  	&dev_attr_legacy_ch11_dimm_label.attr.attr,
> +	&dev_attr_legacy_ch12_dimm_label.attr.attr,
> +	&dev_attr_legacy_ch13_dimm_label.attr.attr,
> +	&dev_attr_legacy_ch14_dimm_label.attr.attr,
> +	&dev_attr_legacy_ch15_dimm_label.attr.attr,
>  	NULL
>  };
>  
> @@ -348,6 +360,14 @@ DEVICE_CHANNEL(ch10_ce_count, S_IRUGO,
>  		   channel_ce_count_show, NULL, 10);
>  DEVICE_CHANNEL(ch11_ce_count, S_IRUGO,
>  		   channel_ce_count_show, NULL, 11);
> +DEVICE_CHANNEL(ch12_ce_count, S_IRUGO,
> +		   channel_ce_count_show, NULL, 12);
> +DEVICE_CHANNEL(ch13_ce_count, S_IRUGO,
> +		   channel_ce_count_show, NULL, 13);
> +DEVICE_CHANNEL(ch14_ce_count, S_IRUGO,
> +		   channel_ce_count_show, NULL, 14);
> +DEVICE_CHANNEL(ch15_ce_count, S_IRUGO,
> +		   channel_ce_count_show, NULL, 15);
>  
>  /* Total possible dynamic ce_count attribute file table */
>  static struct attribute *dynamic_csrow_ce_count_attr[] = {
> @@ -363,6 +383,10 @@ static struct attribute *dynamic_csrow_ce_count_attr[] = {
>  	&dev_attr_legacy_ch9_ce_count.attr.attr,
>  	&dev_attr_legacy_ch10_ce_count.attr.attr,
>  	&dev_attr_legacy_ch11_ce_count.attr.attr,
> +	&dev_attr_legacy_ch12_ce_count.attr.attr,
> +	&dev_attr_legacy_ch13_ce_count.attr.attr,
> +	&dev_attr_legacy_ch14_ce_count.attr.attr,
> +	&dev_attr_legacy_ch15_ce_count.attr.attr,
>  	NULL
>  };

This is also slowly getting out of hand. All those should be allocated
and initialized dynamically based on a number of MCs but not keep adding them
here ad absurdum.

Because if we were doing them dynamically, we'd never ever miss any new
channels when the hw grows...

Thx.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette