Ingo Molnar wrote: > there's no need to disable the VDSO for old userspace ... > Well, apart from the obvious question to which nobody actually knows the answer, (how many people run old user space that required CONFIG_COMPAT_VDSO), what do you think of reversing the boot option? vdso=enabled (default - turn on VDSO on normal boots) vdso=disabled (turn off VDSO unconditionally) [vdso=compat] (default for COMPAT_VDSO - keep VDSO only when mapped at compat location. Note the option is not required to be implemented because it is logically implied from vdso=enabled && COMPAT_VDSO and the default boot behavior) vdso=force (keep VDSO even when moved to a new location and COMPAT_VDSO is enabled). In our case, installing VMware tools in the guest would then detect if userspace supports VDSO or if it requires COMPAT_VDSO and would then set boot parameters for the kernel appropriately. And the native boot and kvm paravirt-ops boot are completely unaffected. Zach
