From owner-freebsd-hackers Tue May 22 14:12:46 2001 Delivered-To: freebsd-hackers@freebsd.org Received: from earth.backplane.com (earth-nat-cw.backplane.com [208.161.114.67]) by hub.freebsd.org (Postfix) with ESMTP id A47DF37B422; Tue, 22 May 2001 14:12:43 -0700 (PDT) (envelope-from dillon@earth.backplane.com) Received: (from dillon@localhost) by earth.backplane.com (8.11.3/8.11.2) id f4MLCh610392; Tue, 22 May 2001 14:12:43 -0700 (PDT) (envelope-from dillon) Date: Tue, 22 May 2001 14:12:43 -0700 (PDT) From: Matt Dillon Message-Id: <200105222112.f4MLCh610392@earth.backplane.com> To: John Baldwin Cc: hackers@FreeBSD.org, "Brian F. Feldman" Subject: Re: RE: vmspace leak (+ tentative fix) References: Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG : : :On 22-May-01 Matt Dillon wrote: :>:Ok, then why not let the current shmexit() stay in exit1() as a hack to help :>:free memory, but add in a check in vmspace_free() as well to catch any race :>:conditions that may fall through the cracks? As long as we clear the shm :>:pointer in struct vmspace when we free it then we won't be double free'ing, :>:and :>:will always free it eventually. That is also a much simpler change. :) :>:Additionally, adding to the comment in exit1() clarifying that this is an :>:attempt to free resources as soon as possible and that the race condition is :>:known and that vmspace_free() is a catch-all might be nice as well. :>: :>:-- :>: :>:John Baldwin -- http://www.FreeBSD.org/~jhb/ :>:PGP Key: http://www.baldwin.cx/~john/pgpkey.asc :> :> It's not really good programming practice. Someone might trip over :> it later on. : :Then the vmspace free()ing is also bad programming practice? It's the same :exact algorithm used for the vmspace. : :> -Matt : :John Baldwin -- http://www.FreeBSD.org/~jhb/ Huh? It doesn't look like the same algorithm to me. -Matt To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message