Re: [PATCH v5 1/2] devcoredump: remove the useless gfp_t parameter in dev_coredumpv and dev_coredumpm

[Brian Norris]

On Fri, Jun 03, 2022 at 01:09:34PM +0800, Duoming Zhou wrote:
> The dev_coredumpv() and dev_coredumpm() could not be used in atomic
> context, because they call kvasprintf_const() and kstrdup() with
> GFP_KERNEL parameter. The process is shown below:
> 
> dev_coredumpv(.., gfp_t gfp)
>   dev_coredumpm(.., gfp_t gfp)
>     dev_set_name
>       kobject_set_name_vargs
>         kvasprintf_const(GFP_KERNEL, ...); //may sleep
>           kstrdup(s, GFP_KERNEL); //may sleep
> 
> This patch removes gfp_t parameter of dev_coredumpv() and dev_coredumpm()
> and changes the gfp_t parameter of kzalloc() in dev_coredumpm() to
> GFP_KERNEL in order to show they could not be used in atomic context.
> 
> Fixes: 833c95456a70 ("device coredump: add new device coredump class")
> Signed-off-by: Duoming Zhou <duoming@xxxxxxxxxx>

For whatever it's worth:

Reviewed-by: Brian Norris <briannorris@xxxxxxxxxxxx>