From: Mark Rutland mark.rutland@arm.com
commit b0de0ccc8b9edd8846828e0ecdc35deacdf186b0 upstream.
Booting a v4.11-rc1 kernel with DEBUG_VIRTUAL and KASAN enabled produces the following splat (trimmed for brevity):
[ 0.000000] virt_to_phys used for non-linear address: ffff200008080000 (0xffff200008080000) [ 0.000000] WARNING: CPU: 0 PID: 0 at arch/arm64/mm/physaddr.c:14 __virt_to_phys+0x48/0x70 [ 0.000000] PC is at __virt_to_phys+0x48/0x70 [ 0.000000] LR is at __virt_to_phys+0x48/0x70 [ 0.000000] Call trace: [ 0.000000] [<ffff2000080b1ac0>] __virt_to_phys+0x48/0x70 [ 0.000000] [<ffff20000a03b86c>] kasan_init+0x1c0/0x498 [ 0.000000] [<ffff20000a034018>] setup_arch+0x2fc/0x948 [ 0.000000] [<ffff20000a030c68>] start_kernel+0xb8/0x570 [ 0.000000] [<ffff20000a0301e8>] __primary_switched+0x6c/0x74
This is because we use virt_to_pfn() on a kernel image address when trying to figure out its nid, so that we can allocate its shadow from the same node.
As with other recent changes, this patch uses lm_alias() to solve this.
We could instead use NUMA_NO_NODE, as x86 does for all shadow allocations, though we'll likely want the "real" memory shadow to be backed from its corresponding nid anyway, so we may as well be consistent and find the nid for the image shadow.
Cc: Catalin Marinas catalin.marinas@arm.com Cc: Will Deacon will.deacon@arm.com Acked-by: Laura Abbott labbott@redhat.com Signed-off-by: Mark Rutland mark.rutland@arm.com Signed-off-by: Will Deacon will.deacon@arm.com Signed-off-by: Andrey Konovalov andreyknvl@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/arm64/mm/kasan_init.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/arch/arm64/mm/kasan_init.c +++ b/arch/arm64/mm/kasan_init.c @@ -153,7 +153,7 @@ void __init kasan_init(void) clear_pgds(KASAN_SHADOW_START, KASAN_SHADOW_END);
vmemmap_populate(kimg_shadow_start, kimg_shadow_end, - pfn_to_nid(virt_to_pfn(_text))); + pfn_to_nid(virt_to_pfn(lm_alias(_text))));
/* * vmemmap_populate() has populated the shadow region that covers the