Re: [PATCH] sysfs/cpu: Make crash_hotplug attribute world-readable

[Sourabh Jain]

Hello Petr,

Just want to mentioned few points about the commit message. No strong
opinion on changing the commit message.

On 11/07/24 16:04, Petr Tesarik wrote:
> From: Petr Tesarik <ptesarik@xxxxxxxx>
>
> There is no reason to restrict access to this attribute, as it merely
> reports whether crash elfcorehdr is automatically updated on CPU hot
> plug/unplug and/or online/offline events.

Now, it is not just elfcorehdr; there could be multiple kexec segments 
based on the architecture's needs.
For example, on PowerPC, it is elfcorehdr and FDT.

> Note that since commit 79365026f8694 ("crash: add a new kexec flag for
> hotplug support"), this maps to the same flag which is world-accessible
> through /sys/devices/system/memory/crash_hotplug.

The previous comment is more relevant for the kexec_load system call.

For the kexec_file_load system call, the kexec flag introduced in the 
commit message
mentioned above is irrelevant. Building kernel with CONFIG_CRASH_HOTPLUG 
is enough.

> Signedoff-by: Petr Tesarik <ptesarik@xxxxxxxx>
> ---
>   drivers/base/cpu.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c
> index c61ecb0c2ae2..73d69791d0d3 100644
> --- a/drivers/base/cpu.c
> +++ b/drivers/base/cpu.c
> @@ -308,7 +308,7 @@ static ssize_t crash_hotplug_show(struct device *dev,
>   {
>   	return sysfs_emit(buf, "%d\n", crash_check_hotplug_support());
>   }
> -static DEVICE_ATTR_ADMIN_RO(crash_hotplug);
> +static DEVICE_ATTR_RO(crash_hotplug);

I agree, it doesn't have to be readable by admin only.

Acked-by: Sourabh Jain <sourabhjain@xxxxxxxxxxxxx>


Thanks for the patch.
- Sourabh