[PATCH] ARM64: kasan: print memory assignment

Linus Walleij linus.walleij at linaro.org
Tue May 26 02:27:44 PDT 2015


This prints out the virtual memory assigned to KASan in the
boot crawl along with other memory assignments, if and only
if KASan is activated.

Example dmesg from the Juno Development board:

Memory: 1691156K/2080768K available (5465K kernel code, 444K rwdata,
2160K rodata, 340K init, 217K bss, 373228K reserved, 16384K cma-reserved)
Virtual kernel memory layout:
    kasan   : 0xffffff8000000000 - 0xffffff9000000000   (    64 MB)
    vmalloc : 0xffffff9000000000 - 0xffffffbdbfff0000   (   182 GB)
    vmemmap : 0xffffffbdc0000000 - 0xffffffbfc0000000   (     8 GB maximum)
              0xffffffbdc2000000 - 0xffffffbdc3fc0000   (    31 MB actual)
    fixed   : 0xffffffbffabfd000 - 0xffffffbffac00000   (    12 KB)
    PCI I/O : 0xffffffbffae00000 - 0xffffffbffbe00000   (    16 MB)
    modules : 0xffffffbffc000000 - 0xffffffc000000000   (    64 MB)
    memory  : 0xffffffc000000000 - 0xffffffc07f000000   (  2032 MB)
      .init : 0xffffffc0007f5000 - 0xffffffc00084a000   (   340 KB)
      .text : 0xffffffc000080000 - 0xffffffc0007f45b4   (  7634 KB)
      .data : 0xffffffc000850000 - 0xffffffc0008bf200   (   445 KB)

Signed-off-by: Linus Walleij <linus.walleij at linaro.org>
---
Done on top of Andrey's patch set obviously.

Andrey: do what you want with this, I think it's kinda nice,
you can harvest this patch for your patch series if you like,
or squash into the ARM64 enablement patch, I have no preference.
I'm testing out KASan on the Juno hardware.
---
 arch/arm64/mm/init.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 597831bdddf3..066dc5e15c48 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -298,6 +298,9 @@ void __init mem_init(void)
 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
 
 	pr_notice("Virtual kernel memory layout:\n"
+#ifdef CONFIG_KASAN
+		  "    kasan   : 0x%16lx - 0x%16lx   (%6ld MB)\n"
+#endif
 		  "    vmalloc : 0x%16lx - 0x%16lx   (%6ld GB)\n"
 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 		  "    vmemmap : 0x%16lx - 0x%16lx   (%6ld GB maximum)\n"
@@ -310,6 +313,9 @@ void __init mem_init(void)
 		  "      .init : 0x%p" " - 0x%p" "   (%6ld KB)\n"
 		  "      .text : 0x%p" " - 0x%p" "   (%6ld KB)\n"
 		  "      .data : 0x%p" " - 0x%p" "   (%6ld KB)\n",
+#ifdef CONFIG_KASAN
+		  MLG(KASAN_SHADOW_START, KASAN_SHADOW_END),
+#endif
 		  MLG(VMALLOC_START, VMALLOC_END),
 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 		  MLG((unsigned long)vmemmap,
-- 
1.9.3




More information about the linux-arm-kernel mailing list