On Mon, Oct 30, 2017 at 04:12:13PM +0000, Alex Bennée wrote: > > Dave Martin <Dave.Martin@xxxxxxx> writes: > > > On Fri, Oct 27, 2017 at 06:52:50PM +0100, Alex Bennée wrote: > >> > >> Dave Martin <Dave.Martin@xxxxxxx> writes: > >> > >> > This patch adds two arm64-specific prctls, to permit userspace to > >> > control its vector length: > >> > > >> > * PR_SVE_SET_VL: set the thread's SVE vector length and vector > >> > length inheritance mode. > >> > > >> > * PR_SVE_GET_VL: get the same information. > >> > > >> > Although these prctls resemble instruction set features in the SVE > >> > architecture, they provide additional control: the vector length > >> > inheritance mode is Linux-specific and nothing to do with the > >> > architecture, and the architecture does not permit EL0 to set its > >> > own vector length directly. Both can be used in portable tools > >> > without requiring the use of SVE instructions. > >> > > >> > Signed-off-by: Dave Martin <Dave.Martin@xxxxxxx> > >> > Reviewed-by: Catalin Marinas <catalin.marinas@xxxxxxx> > >> > Cc: Alex Bennée <alex.bennee@xxxxxxxxxx> > >> > >> FYI there is a minor conflict applying this on current master. > > > > There are some trivial conflicts with one or two patches that already > > went into arm64/for-next/core, so I based on that for this posting, not > > torvalds/master. > > > > There's a note in the cover letter giving the precise commit I based > > on, though the branch doesn't seem to have moved yet since I posted. > > Ahh probably those. It was only a few header file shuffles. I was > rushing to apply before my flight back I failed to note the change in > base commit. > > > > > Otherwise, I don't see any conflict -- can you give details? > > Only that #endif _ASM_ had been dropped from the header file. The #ifndef __ASSEMBLY__ ... #endif is added by another in-flight patch, so it depends on whether that patch (from arm64/for-next/core) is already applied. Cheers ---Dave
