lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Message-Id: <200710080156.IFB56934.tHMLFFJSFOVOOQ@I-love.SAKURA.ne.jp> Date: Mon, 8 Oct 2007 01:56:30 +0900 From: Tetsuo Handa <penguin-kernel@...ove.SAKURA.ne.jp> To: junwang1234@...il.com, a.p.zijlstra@...llo.nl Cc: linux-kernel@...r.kernel.org, linux-security-module@...r.kernel.org Subject: Re: Sleeping in RCU list traversal Hello. Jun WANG wrote: > I'm sorry,I think I got your idea, if you do not need ptr in > my_task_that_may_sleep(), why you need to grab a reference to "ptr". If > your my_task_that_may_sleep() needs ptr, and according to the > "memory region pointed by "ptr" never be removed." you say, > it is ok to use "ptr" after rcu_read_ulock(). The basic idea behind RCU > is to split updates into "removal" and "reclamation" phases. If you > memory region pointed by "ptr" will not "reclamation" in sleep, it is ok I need "ptr" in my_task_that_may_sleep(), but regarding my case, memory region pointed by "ptr" will never be kfree()ed. So, I don't need to grab a reference to "ptr" because memory region pointed by "ptr" will never be kfree()ed. And it is legal to use "ptr" after rcu_read_unlock() because memory region pointed by "ptr" will never be kfree()ed. Thank you. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists