Re: [RFC][PATCH] sysctl: Remove the sysctl system call

[Eric W. Biederman]

Arnd Bergmann <arnd@xxxxxxxx> writes:

> On Wed, Oct 2, 2019 at 12:54 AM Eric W. Biederman <ebiederm@xxxxxxxxxxxx> wrote:
>> Kees Cook <keescook@xxxxxxxxxxxx> writes:
>> > On Tue, Oct 01, 2019 at 01:36:32PM -0500, Eric W. Biederman wrote:
>> >
>> > I think you can actually take this further and remove (or at least
>> > empty) the uapi/linux/sysctl.h file too.
>>
>> I copied everyone who had put this into a defconfig and I will wait a
>> little more to see if anyone screams.  I think it is a safe guess that
>> several of the affected configurations are dead (or at least
>> unmaintained) as I received 17 bounces when copying everyone.
>
> Looking at the arm defconfigs:
>
>> arch/arm/configs/axm55xx_defconfig:CONFIG_SYSCTL_SYSCALL=y
>
> No notable work on this platform since it got sold to Intel in 2014.
> I think they still use it but not with mainline kernels that lack support
> for most drivers and the later chips.
>
>> arch/arm/configs/keystone_defconfig:CONFIG_SYSCTL_SYSCALL=y
>
> Not that old either, but this hardware is mostly obsoleted by newer variants
> that we support with the arm64 defconfig.
>
>> arch/arm/configs/lpc32xx_defconfig:CONFIG_SYSCTL_SYSCALL=y
>> arch/arm/configs/moxart_defconfig:CONFIG_SYSCTL_SYSCALL=y
>
> Ancient hardware, but still in active use. These tend to have very little
> RAM, but they both enable CONFIG_PROC_FS.
>
>> arch/arm/configs/qcom_defconfig:CONFIG_SYSCTL_SYSCALL=y
>> arch/arm/configs/zx_defconfig:CONFIG_SYSCTL_SYSCALL=y
>
> These are for older Qualcomm and LG chips that tend to be used
> with Android rather than the defconfig here. Maybe double-check
> if the official android-common tree enables SYSCTL_SYSCALL.

I just looked quickly at:
https://android.googlesource.com/kernel/configs/

I don't see the string SYSCTL mentioned anywhere.  Much less
SYSCTL_SYSCALL.

Eric