On Fri, Jun 29, 2018 at 10:08:59PM +0200, Thomas Gleixner wrote: > On Fri, 29 Jun 2018, Fenghua Yu wrote: > > > On Fri, Jun 29, 2018 at 06:35:39PM +0200, Thomas Gleixner wrote: > > > On Fri, 29 Jun 2018, Dave Hansen wrote: > > > > > > Plus what enforces proper alignment for the other capability related > > > u32 arrays? > > > > Do you want me to enforce unsigned long alignment for all that are used by > > locked BTS/BTR? > > If there are variables which might be unaligned and accessed with locked > instructions and you have them identified, then why are you asking whether > they should be fixed? > > Ignoring them because they do not trigger #AC right now, is only the > correct answer if you are a follower of the 'works by chance' cult. > > Yeah, I know that most of this industry just works by chance.... >
Ok. I can work on fixing alignment for these instructions in next version. How to handle data that is used in generic code which can be used on non-Intel platform? For exmple, if I do this change for struct efi in include/linux/efi.h because set_bit() sets bits in efi.flags: - unsigned long flags; + unsigned long flags __aligned(unsigned long); } efi; People may argue that the alignment unnecessarily increases size of 'efi' on non-Intel platform which doesn't have split lock issue. Do we care this argument? Another question, there will be a bunch of one-line changes for the alignment (i.e. adding __aligned(unsigned long)) in various files. Will the changes be put in one big patch or in separate one-liner patches? Thanks. -Fenghua
