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Biederman" Cc: Andrew Morton , Andy Lutomirski , Kees Cook , Kusaram Devineni , Peter Zijlstra , Thomas Gleixner , Will Drewry , linux-kernel@vger.kernel.org, Linus Torvalds Subject: Re: [PATCH 0/11] Short circuit delivery for coredump signals Message-ID: References: <87o6gx9rc4.fsf@email.froward.int.ebiederm.org> <877bnh7tnf.fsf@email.froward.int.ebiederm.org> <875x315jh0.fsf@email.froward.int.ebiederm.org> <87ldbr4yn3.fsf@email.froward.int.ebiederm.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87ldbr4yn3.fsf@email.froward.int.ebiederm.org> X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 On 07/03, Eric W. Biederman wrote: > > Oleg Nesterov writes: > > > Yes, the coredumping process is not dead. Yet. It can do a lot of activity > > and use a lot of resources. > > It is semantically dead. Pragmatically I completely agree. > > >> Do you know of something where userspace actually depends upon > >> killing a coredump before it even starts? > > > > Well. I think a user has all rights to assume that SIGKILL must always > > terminate the process asap, the process killed by SIGKILL must not start > > the coredumping. > > If we arrange things so that semantically SIGKILL is delivered before > the signal that triggers the coredump, we can do that without semantic > complications. The window is tiny enough I am not certain it matters. Well, I still disagree, but let's not argue about this. SIGKILL can be lost. IMO, this is an unnecessary regression which should be avoided, regardless of how unlikely or harmless it may seem. > There are other issues with that part of code as well. > > Can we please look at all of these issues after I post the next version > of my patchset (later today)? I don't think anything else depends upon them. Eric, I see you sent V2. Sorry! I didn't have time to take a look. I'll try to read your patches next week when I get back to work. Hopefully on Wednesday. Sorry for delay. Oleg.