Hi, David, On Thu, Feb 2, 2023 at 5:01 PM David Laight <David.Laight@xxxxxxxxxx> wrote: > > From: Huacai Chen > > Sent: 02 February 2023 08:43 > > > > Introduce Kconfig option ARCH_STRICT_ALIGN to make -mstrict-align be > > configurable. > > > > Not all LoongArch cores support h/w unaligned access, we can use the > > -mstrict-align build parameter to prevent unaligned accesses. > > > > This option is disabled by default to optimise for performance, but you > > can enabled it manually if you want to run kernel on systems without h/w > > unaligned access support. > > Should there be an associated run-time check during kernel initialisation > that a kernel compiled without -mstrict-align isn't being run on hardware > that doesn't support unaligned accesses. > > It can be quite a while before you get a compiler-generated misaligned accesses. If we don't use -mstrict-align, the kernel cannot be run on hardware that doesn't support unaligned accesses, so I think the run-time check is useless, and it has no chance to run the checking. > > Also isn't there a HAVE_EFFICIENT_MISALIGNED_ACCESS define that would > also need to be set correctly?? Yes, HAVE_EFFICIENT_MISALIGNED_ACCESS should be kept consistency with ARCH_STRICT_ALIGN, thank you. Huacai > > David > > - > Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK > Registration No: 1397386 (Wales) >
