Rusty Russell wrote:
Hm, I guess, so long as you assume the kernel data segment is always below the kernel heap.I don't think so. There's *never* address subtraction, there's sometimes 32 bit wrap (glibc uses this to effect subtraction, sure). But there's no wrap here.
To test, I changed the following: --- smpboot.c.~8~ 2006-09-25 15:51:50.000000000 +1000 +++ smpboot.c 2006-09-25 16:00:36.000000000 +1000 @@ -926,8 +926,9 @@ unsigned long per_cpu_off) { unsigned limit, flags; + extern char __per_cpu_end[];- limit = (1 << 20);+ limit = PAGE_ALIGN((long)__per_cpu_end) >> PAGE_SHIFT;
limit is a size, rather than the end address, so this isn't quite right. J - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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