The BSS section has already cleared out in the first pass. No need to
clear it again. This can save some time when booting with KASLR
enabled.
Signed-off-by: Jason Yan <[email protected]>
Cc: Scott Wood <[email protected]>
Cc: Diana Craciun <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Christophe Leroy <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Paul Mackerras <[email protected]>
Cc: Nicholas Piggin <[email protected]>
Cc: Kees Cook <[email protected]>
---
arch/powerpc/kernel/head_64.S | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S
index 454129a3c259..9354c292b709 100644
--- a/arch/powerpc/kernel/head_64.S
+++ b/arch/powerpc/kernel/head_64.S
@@ -913,6 +913,13 @@ start_here_multiplatform:
bl relative_toc
tovirt(r2,r2)
+ /* Do not clear the BSS for the second pass if randomized */
+ LOAD_REG_ADDR(r3, kernstart_virt_addr)
+ ld r3,0(r3)
+ LOAD_REG_IMMEDIATE(r4, KERNELBASE)
+ cmpd r3,r4
+ bne 4f
+
/* Clear out the BSS. It may have been done in prom_init,
* already but that's irrelevant since prom_init will soon
* be detached from the kernel completely. Besides, we need
--
2.17.2