2015-08-15 0:38 GMT+02:00 Andy Lutomirski <l...@amacapital.net>: > Would you all consider it acceptable to disallow watchpoints on per > cpu data entirely? I can think of a *lot* of places where hitting #DB > when accessing per cpu data from entry asm would be bad. > > Of course, actually implementing that might be less than entirely fun, > given that a cpu could be onlined after creating a watchpoint.
Well I think there will always be places where setting a breakpoint is a bad idea. The same goes for kprobes. We can't fix all of them. Kernel breakpoints can only be set by root users so it's not a security issue. Besides, kernel breakpoints should only be used by kernel hackers (perf, kdb). Given the wide use of per-cpu data, forbidding all of them will seriously reduce the usability of kernel breakpoints. Not that I think they are really used in practice though ;-) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
