On Thursday 05 May 2016 18:35:45 Horia Geantă wrote: > While reviewing the addition of io{read,write}64be accessors, Arnd > > -finds a potential problem: > "If an architecture overrides readq/writeq to have barriers but does > not override ioread64be/iowrite64be, this will lack the barriers and > behave differently from the little-endian version. I think the only > affected architecture is ARC, since ARM and ARM64 both override the > big-endian accessors to have the correct barriers, and all others > don't use barriers at all." > > -suggests a fix for the same problem in existing code (16/32-bit > accessors); the fix leads "to a double-swap on architectures that > don't override the io{read,write}{16,32}be accessors, but it will > work correctly on all architectures without them having to override > these accessors." > > Suggested-by: Arnd Bergmann <arnd@xxxxxxxx> > Signed-off-by: Horia Geantă <horia.geanta@xxxxxxx> > --- Acked-by: Arnd Bergmann <arnd@xxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html