linux-kernel - Re: [PATCH-next 2/3] sysctl/sysrq: Remove __sysrq

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Date:   Fri, 10 Jan 2020 23:01:37 +0100
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     Dmitry Safonov <dima@...sta.com>
Cc:     linux-kernel@...r.kernel.org,
        Dmitry Safonov <0x7f454c46@...il.com>,
        Jiri Slaby <jslaby@...e.com>,
        Vasiliy Khoruzhick <vasilykh@...sta.com>,
        linux-serial@...r.kernel.org, Iurii Zaikin <yzaikin@...gle.com>,
        Luis Chamberlain <mcgrof@...nel.org>,
        Kees Cook <keescook@...omium.org>,
        linux-fsdevel@...r.kernel.org
Subject: Re: [PATCH-next 2/3] sysctl/sysrq: Remove __sysrq_enabled copy

On Fri, Jan 10, 2020 at 09:45:30PM +0000, Dmitry Safonov wrote:
> Hi Greg,
> 
> On 1/10/20 4:40 PM, Greg Kroah-Hartman wrote:
> > On Thu, Jan 09, 2020 at 09:54:43PM +0000, Dmitry Safonov wrote:
> [..]
> >> @@ -2844,6 +2827,26 @@ static int proc_dostring_coredump(struct ctl_table *table, int write,
> >>  }
> >>  #endif
> >>  
> >> +#ifdef CONFIG_MAGIC_SYSRQ
> >> +static int sysrq_sysctl_handler(struct ctl_table *table, int write,
> >> +				void __user *buffer, size_t *lenp, loff_t *ppos)
> >> +{
> >> +	int tmp, ret;
> >> +
> >> +	tmp = sysrq_get_mask();
> >> +
> >> +	ret = __do_proc_dointvec(&tmp, table, write, buffer,
> >> +			       lenp, ppos, NULL, NULL);
> >> +	if (ret || !write)
> >> +		return ret;
> >> +
> >> +	if (write)
> >> +		sysrq_toggle_support(tmp);
> >> +
> >> +	return 0;
> >> +}
> >> +#endif
> > 
> > Why did you move this function down here?  Can't it stay where it is and
> > you can just fix the logic there?  Now you have two different #ifdef
> > blocks intead of just one :(
> 
> Yeah, well __do_proc_dointvec() made me do it.
> 
> sysrq_sysctl_handler() declaration should be before ctl_table array of
> sysctls, so I couldn't remove the forward-declaration.
> 
> So, I could forward-declare __do_proc_dointvec() instead, but looking at
> the neighborhood, I decided to follow the file-style (there is a couple
> of forward-declarations before the sysctl array, some under ifdefs).
> 
> I admit that the result is imperfect and can put __do_proc_dointvec()
> definition before instead, no hard feelings.

Ah, no, nevermind, I missed that reason, sorry about that.  Moving it is
fine.

greg k-h