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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, May 06, 2020 at 04:25:52PM +0100, Mark Brown wrote: > On Wed, May 06, 2020 at 03:45:44PM +0100, Will Deacon wrote: > > On Wed, May 06, 2020 at 02:40:21PM +0100, Dave Martin wrote: > > > > I really don't think we should fudge this: if the linker doesn't think > > > the inputs are BTI-enabled then the compiler or linker is broken, or > > > there's a bug in the kernel source tree. > > > > The checking done by the toolchain is important -- if we want to > > > suppress it, we should have an override option than depends on BROKEN > > > (because yes, you're explicitly risking a broken kernel if you do this). > > > > The fact that all gcc and clang both screwed this up in various ways at > > > some point is not our fault, or our problem, providing that fixes are > > > available... > > > > Am I being too paranoid? > > That's my position too, we want the warning - I think if we're going to > do any handling it should either be to prevent use of kernel BTI > entirely or to do what Will was originally suggesting and print some > explanatory text somewhere. My inclination is that the former is safer > and fits more with the general architecture approach to this sort of > thing. > > > I don't think so, but I'm just looking for an answer to "What do we do if > > people start running into this warning?". As it stands, it sounds like it's > > unlikely that they will, but if they do then we're going to have to hack > > something to make it go away. > > It's possible that this e-mail thread showing up in searches might well > answer people's questions anyway (it is going to be one of the few hits > for the warning ATM). How about we deal with this when we get to it, or > at least as a followup? Yes, I don't think it's worth writing patches for this now, just wanted to get a vague idea of our options if people start complaining. Cheers, Will _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel