Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Fri, 20 Jan 2023 16:22:51 +0100
From:   Oleg Nesterov <oleg@redhat.com>
To:     Gregory Price <gourry.memverge@gmail.com>
Cc:     linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org,
        krisman@collabora.com, tglx@linutronix.de, luto@kernel.org,
        peterz@infradead.org, ebiederm@xmission.com,
        akpm@linux-foundation.org, adobriyan@gmail.com, corbet@lwn.net,
        shuah@kernel.org, Gregory Price <gregory.price@memverge.com>
Subject: Re: [PATCH v3 1/3] ptrace,syscall_user_dispatch: Implement Syscall
 User Dispatch Suspension
Message-ID: <20230120152250.GA9801@redhat.com>
References: <20230120144356.40717-1-gregory.price@memverge.com>
 <20230120144356.40717-2-gregory.price@memverge.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20230120144356.40717-2-gregory.price@memverge.com>
User-Agent: Mutt/1.5.24 (2015-08-30)
Precedence: bulk

Hi Gregory,

I'll try to read this series next Monday, I need to recall what does
syscall-user-dispatch actually do ;)

just one question for now,

On 01/20, Gregory Price wrote:
>
> --- a/kernel/ptrace.c
> +++ b/kernel/ptrace.c
> @@ -370,6 +370,10 @@ static int check_ptrace_options(unsigned long data)
>  	if (data & ~(unsigned long)PTRACE_O_MASK)
>  		return -EINVAL;
>  
> +	if (unlikely(data & PTRACE_O_SUSPEND_SYSCALL_USER_DISPATCH) &&
> +	    (!IS_ENABLED(CONFIG_CHECKPOINT_RESTART)))
> +			return -EINVAL;

Hmm? git grep CHECKPOINT_RESTART shows nothing.

Oleg.