On Tue, Apr 14, 2020 at 08:27:26PM +0200, Peter Zijlstra wrote: > On Tue, Apr 14, 2020 at 11:28:36AM -0500, Josh Poimboeuf wrote: > > Better late than never, these patches add simplifications and > > improvements for some issues Peter found six months ago, as part of his > > non-writable text code (W^X) cleanups. > > Excellent stuff, thanks!! > > I'll go brush up these two patches then: > > https://lkml.kernel.org/r/20191018074634.801435443@xxxxxxxxxxxxx > https://lkml.kernel.org/r/20191018074634.858645375@xxxxxxxxxxxxx Ah right, I meant to bring that up. I actually played around with those patches. While it would be nice to figure out a way to converge the ftrace module init, I didn't really like the first patch. It bothers me that both the notifiers and the module init() both see the same MODULE_STATE_COMING state, but only in the former case is the text writable. I think it's cognitively simpler if MODULE_STATE_COMING always means the same thing, like the comments imply, "fully formed" and thus not-writable: enum module_state { MODULE_STATE_LIVE, /* Normal state. */ MODULE_STATE_COMING, /* Full formed, running module_init. */ MODULE_STATE_GOING, /* Going away. */ MODULE_STATE_UNFORMED, /* Still setting it up. */ }; And, it keeps tighter constraints on what a notifier can do, which is a good thing if we can get away with it. > and write a patch that makes the x86 code throw a wobbly on W+X. > > Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Thanks! -- Josh
