From mboxrd@z Thu Jan 1 00:00:00 1970 From: Xiao Yang Date: Wed, 30 Sep 2020 20:27:59 +0800 Subject: [LTP] [PATCH] controllers/cpuset_base_ops_testset.sh: Accept either 0 or -EINVAL when passing '0-' In-Reply-To: <20200930104709.GC6611@yuki.lan> References: <20200929025606.322543-1-yangx.jy@cn.fujitsu.com> <20200930104709.GC6611@yuki.lan> Message-ID: <5F7479CF.4090007@cn.fujitsu.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ltp@lists.linux.it On 2020/9/30 18:47, Cyril Hrubis wrote: > Hi! >> When we write '0-' to cpuset.cpus/cpuset.mems, new bitmap_parselist() >> in kernel(e.g. newer than v4.2) treats it as an invalid value and old >> one treats it as a valid '0': >> ------------------------------------------- >> on v5.8.0: >> # echo 0-> cpuset.cpus >> -bash: echo: write error: Invalid argument >> # echo 0-> cpuset.mems >> -bash: echo: write error: Invalid argument >> >> on v4.0.0: >> # echo '0-'>cpuset.cpus >> # cat cpuset.cpus >> 0 >> # echo '0-'>cpuset.mems >> # cat cpuset.cpus >> 0 >> ------------------------------------------- >> Note: commit d9282cb66353b changes the behavior. >> >> Drop the check of kernel version and accept either 0 or -EINVAL >> because the change of behavior can be backported into old kernel. > Why can't we just simply adjust the kernel check, it looks like the > commit you mentioned was added to 4.3 so it should be fixed by changing > the line to: > > if tst_kvcmp -lt "4.3 RHEL6:2.6.32"; then > > We want to at least keep the check for kernels newer than 4.3 just to > make sure that kernel keeps rejecting the '0-' invalid value. Hi Cyril, Thanks for your reply. :-) 1) I still got '0' value instead of -EINVAL on Centos 6.10(2.6.32-754) so not sure why we have the wrong kernel check before. Perhaps, is there anothe older kernel commit to change the behavior as well? 2) I don't think that kernel check is enough because the change of behavior may be backported into old kernel. How about removing the combination directly as Richard suggested on #695. Best Regards, Xiao Yang -------------- next part -------------- An HTML attachment was scrubbed... URL: