git: kernel - Fix some rare pmap races in i386 and x86_64.

[Aggelos Economopoulos]

Matthew Dillon wrote:
[...]
>     * Interlock the pmap structure when invalidating pages using a bit
>       in the pm_active field.
>     
>       Check for the interlock in swtch.s when switching into threads
>       and print a nice warning if it occurs.
+       if (pmap->pm_active & CPUMASK_LOCK) {
+               kprintf("Warning: pmap_interlock %08x\n", pmap->pm_active);


Err, this warning is totally meaningless to an administrator or pretty
much anybody who didn't read this patch. Wouldn't something like

kprintf("Diagnostic: pmap_interlock %08x. Please report this!\n",
pmap->pm_active)

or even

kprintf("Wow. pmap_interlock %08x. Please report this!\n", pmap->pm_active)

be more useful to both sides?

Aggelos