From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sukadev Bhattiprolu Subject: Re: [RFC][PATCH 4/6][v3] Define siginfo_from_ancestor_ns() Date: Mon, 22 Dec 2008 15:45:24 -0800 Message-ID: <20081222234524.GB13079@us.ibm.com> References: <20081221005106.GA4912@us.ibm.com> <20081221005424.GD5025@us.ibm.com> <20081222222604.GA1536@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20081222222604.GA1536@redhat.com> Sender: linux-kernel-owner@vger.kernel.org To: Oleg Nesterov Cc: ebiederm@xmission.com, roland@redhat.com, bastian@waldi.eu.org, daniel@hozac.com, xemul@openvz.org, containers@lists.osdl.org, linux-kernel@vger.kernel.org, sukadev@us.ibm.com List-Id: containers.vger.kernel.org Oleg Nesterov [oleg@redhat.com] wrote: | On 12/20, Sukadev Bhattiprolu wrote: | > | > + * TODO: | > + * Making SI_ASYNCIO a kernel signal could make this less hacky. | > + */ | > +#ifdef CONFIG_PID_NS | > +static inline int siginfo_from_user(siginfo_t *info) | > +{ | > + if (!is_si_special(info) && SI_FROMUSER(info) && | | OK, if we can trust SI_FROMUSER(), then it is better, i agree. | | I was worried about in-kernel usage of .si_code <= 0 ... | | > + info->si_code != SI_ASYNCIO) | | but this is horrible, imho. I am beginning to accept that some amount of ugliness is inevitable here :-) I tried to dig through history of SI_ASYNCIO, but did not find any changes to its definition in siginfo.h in 6 years. | | OK, if we can't change the ABI, then perhaps we can change | kill_pid_info_as_uid() to not send the fatal signals to UNKILLABLE | task? This helper is strange and ugly anyway, | | | To clarify, I do not blame the patch itself, and I do not suggest | to do this right now. By 'to do this' I assume you are referring to the kill_pid_info_as_uid() change above ? IOW, ugly as it is, can we go with the siginfo_from_user() as in the patch ?