Messages in this thread Patch in this message |  | | From | Jason Yan <> | Subject | [PATCH v2 4/6] powerpc/fsl_booke/64: do not clear the BSS for the second pass | Date | Wed, 5 Feb 2020 10:55:25 +0800 |
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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@huawei.com> Cc: Scott Wood <oss@buserror.net> Cc: Diana Craciun <diana.craciun@nxp.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Kees Cook <keescook@chromium.org> --- 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
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