On 11/15/19 3:27 PM, Jan Beulich wrote: > On 15.11.2019 16:05, George Dunlap wrote: >> FTR, please avoid top-posting. :-) >> >> On 11/15/19 2:31 PM, Steven Haigh wrote: >>> Just regarding the use of a system environment variable to turn this >>> feature / bugfix / hack on and off - this would probably break starting >>> the VM via the xendomains script. >>> >>> If the VM definition is in /etc/xen/auto/, then there would be nothing >>> to set the environment variable before the VM is launched - hence it >>> would not be applied and a guest crash would occur... >>> >>> Depending on the VM's settings, this would either continue to start & >>> crash - or just stop again until it could be started with the ENV variable. >> >> Right. So a couple of options: >> >> 1. Users of xendomains could set the environment variable in their >> xendomains script >> >> 2. We could add a xl.cfg option. Unknown xl.cfg entries are ignored >> (for better or for worse); in the future, when the "fake ht" thing is >> replaced, we can either continue ignoring it, or give a useful error >> message saying how it should be changed. >> >> 2a. We could have the config option *replace* the environment variable; >> in which case we'd leave libvirt users high and dry >> >> 2b. We could have the config option cause xl to *set* the environment >> variable, which should continue to allow other toolstacks (even those >> not using libxl) to potentially work around the issue. > > And how would any of these allow to deal with heterogeneous sets of > guests?
Are you perhaps confusing 'xl.cfg' (which is the per-domain configuration file) with 'xl.conf' (which is the system-wide configuration file)? #1 would obviously require arranging for *all* xendomain-enabled guests to be started with the config enabled. #2 would allow heterogeneous guests if the admin went through and added the workaround to the guests she wanted. -George _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
