On Wed, 13 May 2015, Toshi Kani wrote: > __ioremap_caller() calls reserve_memtype() to set new_pcm > (existing map type if any), and then calls > is_new_memtype_allowed() to verify if converting to new_pcm > is allowed when pcm (request type) is different from new_pcm. > > When WT is requested, the caller expects that writes are > ordered and uncached. Therefore, this patch changes > is_new_memtype_allowed() to disallow the following cases. > > - If the request is WT, mapping type cannot be WB > - If the request is WT, mapping type cannot be WC > > Signed-off-by: Toshi Kani <toshi.kani@xxxxxx> Reviewed-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>