Re: [PATCH sysctl-next] kernel/kexec_core: move kexec_core sysctls into its own file

Baoquan He
2022-02-23T08:30:24Z

On 02/23/22 at 11:03am, yingelin wrote:
> This move the kernel/kexec_core.c respective sysctls to its own file.

Hmm, why is the move needed?

With my understanding, sysctls are all put in kernel/sysctl.c,
why is kexec special?

>
> Signed-off-by: yingelin <yingelin@huawei.com>
> ---
> kernel/kexec_core.c | 20 ++++++++++++++++++++
> kernel/sysctl.c | 13 -------------
> 2 files changed, 20 insertions(+), 13 deletions(-)
>
> diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
> index 68480f731192..e57339d49439 100644
> --- a/kernel/kexec_core.c
> +++ b/kernel/kexec_core.c
> @@ -936,6 +936,26 @@ int kimage_load_segment(struct kimage *image,
> struct kimage *kexec_image;
> struct kimage *kexec_crash_image;
> int kexec_load_disabled;
> +static struct ctl_table kexec_core_sysctls[] = {
> + {
> + .procname = "kexec_load_disabled",
> + .data = &kexec_load_disabled,
> + .maxlen = sizeof(int),
> + .mode = 0644,
> + /* only handle a transition from default "0" to "1" */
> + .proc_handler = proc_dointvec_minmax,
> + .extra1 = SYSCTL_ONE,
> + .extra2 = SYSCTL_ONE,
> + },
> + { }
> +};
> +
> +static int __init kexec_core_sysctl_init(void)
> +{
> + register_sysctl_init("kernel", kexec_core_sysctls);
> + return 0;
> +}
> +late_initcall(kexec_core_sysctl_init);
>
> /*
> * No panic_cpu check version of crash_kexec(). This function is called
> diff --git a/kernel/sysctl.c b/kernel/sysctl.c
> index ae5e59396b5d..00e97c6d6576 100644
> --- a/kernel/sysctl.c
> +++ b/kernel/sysctl.c
> @@ -61,7 +61,6 @@
> #include <linux/capability.h>
> #include <linux/binfmts.h>
> #include <linux/sched/sysctl.h>
> -#include <linux/kexec.h>
> #include <linux/bpf.h>
> #include <linux/mount.h>
> #include <linux/userfaultfd_k.h>
> @@ -1839,18 +1838,6 @@ static struct ctl_table kern_table[] = {
> .proc_handler = tracepoint_printk_sysctl,
> },
> #endif
> -#ifdef CONFIG_KEXEC_CORE
> - {
> - .procname = "kexec_load_disabled",
> - .data = &kexec_load_disabled,
> - .maxlen = sizeof(int),
> - .mode = 0644,
> - /* only handle a transition from default "0" to "1" */
> - .proc_handler = proc_dointvec_minmax,
> - .extra1 = SYSCTL_ONE,
> - .extra2 = SYSCTL_ONE,
> - },
> -#endif
> #ifdef CONFIG_MODULES
> {
> .procname = "modprobe",
> --
> 2.26.2
>