On Tue, Oct 25, 2022 at 07:02:53PM +0100, Matthew Wilcox wrote: > On Mon, Oct 24, 2022 at 05:18:33PM -0700, Darrick J. Wong wrote: > > On Mon, Oct 24, 2022 at 10:56:48PM +0100, Matthew Wilcox wrote: > > > On Mon, Oct 24, 2022 at 02:32:18PM -0700, Darrick J. Wong wrote: > > > > Fix the incorrect return type for these two functions, and make the > > > > !fsdax version return SIGBUS since there is no vm_fault_t that maps to > > > > zero. > > > > > > Hmm? You should be able to return 0 without sparse complaining. > > > > Yes I know, but is that the correct return value for "someone is calling > > the wrong function, everything is fubar, please stop the world now"? > > No, it's "success, but I didn't bother to lock the page myself, please > do it for me", which doesn't really make any sense. I think in this > case, having not initialised vmf->page, we'd probably take a NULL > ptr dereference in lock_page(). Yes, that's why I don't want to leave the !fsdax stub returning zero. --D > From your changelog, it seemed like you were trying to come up with the > vm_fault_t equivalent of 0, rather than trying to change the semantics > of the !fsdax version.
