-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 7/9/12 3:07 PM, Jean Delvare wrote:
Le lundi 09 juillet 2012 à 10:44 -0400, Jeff Mahoney a écrit :
On 7/9/12 10:37 AM, Jean Delvare wrote:
So, unless someone objects by then, I'll set CONFIG_CC_STACKPROTECTOR=y in i386 and x86_64 kernels tomorrow.
Thanks for looking into this, Jean. Since we don't have a bnc in the commit log to see what the performance degradation looked like originally, I'd like to see some analysis now to actually confirm whether it makes a difference anymore.
openSUSE 12.2 was supposed to be released in two days time but was delayed due to too much churn (among other things). If there is a performance difference, I'd prefer to know about it before we do the change rather than depend on post-release bug reports and the accompanying hand-wringing over whether to revert it.
Are you simply suggesting that I should change the configuration for master only and not the openSUSE-12.2 branch? Or should I wait even for master?
I admit I'm not sure how to test for performance regression. With CONFIG_CC_STACKPROTECTOR_ALL it was relatively obvious, but now that only selected functions get the protection, I can imagine that the performance hit completely depends on the drivers, filesystem etc. in use.
A quick look makes it seem like it really only has an effect during context switch. Mike - What would you use to test this? - -Jeff
It might be easier to check what other distributions are doing, and simply align on that. Richard said that Debian and Fedora "seemed" to enable it by default, it would have to be confirmed, and ideally Ubuntu and RHEL should be checked as well. Unfortunately I don't have any of these at home so I can't check.
- -- Jeff Mahoney SUSE Labs -----BEGIN PGP SIGNATURE----- Version: GnuPG/MacGPG2 v2.0.18 (Darwin) Comment: GPGTools - http://gpgtools.org Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJP+y/bAAoJEB57S2MheeWyv3wP/RRT9N1gnZxGcfXLmq7/dmuP ZPLgnxDzNvHNVt3ZhgQQtb3rbjUUhozMQ45oBFr5fB3uwiyQ/axE4iBc/+T2qMQS GQZrWv1qHcvTkLXnYVQdSKW/tj8OG4HsSPXLZsVFSCj15NNTmAhE9SJpB3+fGRM1 PG1IJght5AO7SjUsSajgtJnUoQMGQByZq2Q1Pv3UA73L8hn1pHY29O27o1PLYZQ9 DaVND8mJwc7lh0fZxM5v4OIKVnIbLscsa2pBpBpLqoVDuAwAKKbFu1UxrrFte44L sIQzQjFH/hQbpWWI2yd1MYcd9gKQ7P674gUlSy2T7fSIG5RREwJWnN3ajyk7/jhm BK3ihXvu3krZSX+3rA+Bo5hQg58IClZxat6N1rDpdob/lUuqYswnwR/ujl8Jxjb4 TzwNyrKkyfEQUeJzKGStjrAh4DczE5IPfOrAfDDHiHWKlzGpI466nqGxJly/saK6 FX0aKjB56j8T/k8KCETIEdMSO+Qsm06DPGKmOhpEJqJkPjnUXA26FxAoQgiatfYV RKJOtSJiBjpILfDSDMdie450B0BFds2BFwr/QdOAxokwWPHRG1r+487Lnpgd2F+3 EABii5mtODrq88MBlMokk68oYUgB6WilwFjXUxsTbEBl6X3LMNzU3pbiaEFvgZQ+ MJC/zTJKYrk1msStMn+O =oHYA -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org