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 <yanaijie@xxxxxxxxxx> Cc: Scott Wood <oss@xxxxxxxxxxxx> Cc: Diana Craciun <diana.craciun@xxxxxxx> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Cc: Christophe Leroy <christophe.leroy@xxxxxx> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Cc: Nicholas Piggin <npiggin@xxxxxxxxx> Cc: Kees Cook <keescook@xxxxxxxxxxxx> --- 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 b4ececc4323d..9ae7fd8bbf7c 100644 --- a/arch/powerpc/kernel/head_64.S +++ b/arch/powerpc/kernel/head_64.S @@ -914,6 +914,13 @@ 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) + lwz r3,0(r3) + LOAD_REG_IMMEDIATE(r4, KERNELBASE) + cmpw 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
