On 05/15/2017, 03:16 PM, Will Deacon wrote: > Whilst I think this is a good idea, the code in question actually results > in undefined behaviour per the C spec and is reported by UBSAN. Hi, yes, I know -- this patch was the 1st from the series of 3 which I sent a long time ago to fix that up too. But I remember your patch, so I sent only this one this time. > See my > patch fixing arm64 here (which I'd forgotten about): > > https://www.spinics.net/lists/linux-arch/msg38564.html > > But, as stated in the thread above, I think we should go a step further > and remove FUTEX_OP_{OR,ANDN,XOR,OPARG_SHIFT} altogether. They don't > appear to be used by userspace, and this whole thing is a total mess. > > Any thoughts? Ok, I am all for that. I think the only question is who is going to do the work and submit it :)? Do I understand correctly to eliminate all these functions and the path into the kernel? But won't this break API -- are there really no users of this interface? thanks, -- js suse labs
