From: bob picco <bob.picco@xxxxxxxxxx> I encountered this bug when using /proc/kcore to examine the kernel. Plus a coworker inquired about debugging tools. We computed pa but did not use it during the maximum physical address bits test. Instead we used the identity mapped virtual address which will always fail this test. I believe the defect came in here: [bpicco@zareason linus.git]$ git describe --contains bb4e6e85daa52 v3.18-rc1~87^2~4 . Signed-off-by: Bob Picco <bob.picco@xxxxxxxxxx> --- arch/sparc/mm/init_64.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c index 5d2f91511c60..47ecac5106d3 100644 --- a/arch/sparc/mm/init_64.c +++ b/arch/sparc/mm/init_64.c @@ -1495,7 +1495,7 @@ bool kern_addr_valid(unsigned long addr) if ((long)addr < 0L) { unsigned long pa = __pa(addr); - if ((addr >> max_phys_bits) != 0UL) + if ((pa >> max_phys_bits) != 0UL) return false; return pfn_valid(pa >> PAGE_SHIFT); -- 2.11.0 -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html