On Tue, Jan 28, 2014 at 05:38:08PM +0100, Oleg Nesterov wrote: > On 01/28, Al Viro wrote: > > > > On Mon, Jan 27, 2014 at 06:39:31PM +0100, Oleg Nesterov wrote: > > > On 01/27, Al Viro wrote: > > > > > > > > Why is _TIF_UPROBE *not* a part > > > > of _TIF_DO_NOTIFY_MASK, for example? > > > > > > Yes, please see another email. That is why uprobe_deny_signal() > > > sets TIF_NOTIFY_RESUME along with TIF_UPROBE. > > > > *grumble* Can it end up modifying *regs? From very cursory reading of > > kernel/events/uprobe.c it seems to do so, so we probably want to leave > > via iretq if that has hit, right? > > But we do this anyway, restore_args path does iretq? > > I mean, uprobe_notify_resume() is called from do_notify_resume(), it > should be fine to modify*regs there?
See Linus' patch trying to avoid iretq path; it's really costly. Looks like that patch will have to treat _TIF_UPROBE the same way it treats _TIF_SIGPENDING... -- 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/
