Date: Mon, 23 Nov 2020 02:49:54 +0000 (UTC) From: Kyle Evans <kevans@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r367944 - head/sys/kern Message-ID: <202011230249.0AN2nsOh059304@repo.freebsd.org>
next in thread | raw e-mail | index | archive | help
Author: kevans Date: Mon Nov 23 02:49:53 2020 New Revision: 367944 URL: https://svnweb.freebsd.org/changeset/base/367944 Log: cpuset_setproc: use the appropriate parent for new anonymous sets As far as I can tell, this has been the case since initially committed in 2008. cpuset_setproc is the executor of cpuset reassignment; note this excerpt from the description: * 1) Set is non-null. This reparents all anonymous sets to the provided * set and replaces all non-anonymous td_cpusets with the provided set. However, reviewing cpuset_setproc_setthread() for some jail related work unearthed the error: if tdset was not anonymous, we were replacing it with `set`. If it was anonymous, then we'd rebase it onto `set` (i.e. copy the thread's mask over and AND it with `set`) but give the new anonymous set the original tdset as the parent (i.e. the base of the set we're supposed to be leaving behind). The primary visible consequences were that: 1.) cpuset_getid() following such assignment returns the wrong result, the setid that we left behind rather than the one we joined. 2.) When a process attached to the jail, the base set of any anonymous threads was a set outside of the jail. This was initially bundled in D27298, but it's a minor fix that's fairly easy to verify the correctness of. A test is included in D27307 ("badparent"), which demonstrates the issue with, effectively: osetid = cpuset_getid() newsetid = cpuset() cpuset_setaffinity(thread) cpuset_setid(osetid) cpuset_getid(thread) -> observe that it matches newsetid instead of osetid. MFC after: 1 week Modified: head/sys/kern/kern_cpuset.c Modified: head/sys/kern/kern_cpuset.c ============================================================================== --- head/sys/kern/kern_cpuset.c Mon Nov 23 00:58:14 2020 (r367943) +++ head/sys/kern/kern_cpuset.c Mon Nov 23 02:49:53 2020 (r367944) @@ -1090,7 +1090,7 @@ cpuset_setproc_setthread(struct cpuset *tdset, struct if (error) return (error); - return cpuset_shadow(tdset, nsetp, &mask, &domain, freelist, + return cpuset_shadow(set, nsetp, &mask, &domain, freelist, domainlist); }
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?202011230249.0AN2nsOh059304>