On 05/17/2010 03:02 PM, Benjamin Herrenschmidt wrote: > On Mon, 2010-05-17 at 11:03 -0700, H. Peter Anvin wrote: >> On 05/14/2010 01:09 AM, Benjamin Herrenschmidt wrote: >>> >>> No. That is not the point. Read the rest of my email ! >>> >>> We need to -sanitize- those errors. _Maybe_ exposing LMB_ERROR is the >>> right way to do so, but in that case, we need to make -all- function use >>> the same error code. Right now, some fail with 0 and some with >>> LMB_ERROR. >>> >> >> Using errnos like the rest of the kernel seems like the right thing to >> do, IMO. > > Maybe. The allocator/find functions return a physical address. If we all > agree that a physical address between -PAGE_SIZE and 0 is never valid, > then we can overlay the negative errno codes like we do for pointers. > > I'll have a look at that, it shouldn't be very hard. > For x86 with 64-bit resource_t, this is always true (physical addresses are never negative.) For x86 with 32-bit resource_t negative physical addresses can be negative, but the top of the address space will always be occupied by the boot ROM (it's a hardware constraint.) -hpa -- 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
