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authorJason Yan <yanaijie@huawei.com>2019-09-20 11:45:40 +0200
committerMichael Ellerman <mpe@ellerman.id.au>2019-11-13 09:27:40 +0100
commit2b0e86cc5de6dabadc2d64cefa429fc227c8a756 (patch)
treefe20c15ad210f0b7aa7aa402ff0ad0e9eaa80bbe /arch/powerpc/kernel/head_fsl_booke.S
parentpowerpc/fsl_booke/32: introduce reloc_kernel_entry() helper (diff)
downloadlinux-2b0e86cc5de6dabadc2d64cefa429fc227c8a756.tar.xz
linux-2b0e86cc5de6dabadc2d64cefa429fc227c8a756.zip
powerpc/fsl_booke/32: implement KASLR infrastructure
This patch add support to boot kernel from places other than KERNELBASE. Since CONFIG_RELOCATABLE has already supported, what we need to do is map or copy kernel to a proper place and relocate. Freescale Book-E parts expect lowmem to be mapped by fixed TLB entries(TLB1). The TLB1 entries are not suitable to map the kernel directly in a randomized region, so we chose to copy the kernel to a proper place and restart to relocate. The offset of the kernel was not randomized yet(a fixed 64M is set). We will randomize it in the next patch. Signed-off-by: Jason Yan <yanaijie@huawei.com> Tested-by: Diana Craciun <diana.craciun@nxp.com> Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net> [mpe: Use PTRRELOC() in early_init()] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/kernel/head_fsl_booke.S')
-rw-r--r--arch/powerpc/kernel/head_fsl_booke.S13
1 files changed, 10 insertions, 3 deletions
diff --git a/arch/powerpc/kernel/head_fsl_booke.S b/arch/powerpc/kernel/head_fsl_booke.S
index d9f599b01ff1..838d9d4650c7 100644
--- a/arch/powerpc/kernel/head_fsl_booke.S
+++ b/arch/powerpc/kernel/head_fsl_booke.S
@@ -155,6 +155,8 @@ _ENTRY(_start);
*/
_ENTRY(__early_start)
+ LOAD_REG_ADDR_PIC(r20, kernstart_virt_addr)
+ lwz r20,0(r20)
#define ENTRY_MAPPING_BOOT_SETUP
#include "fsl_booke_entry_mapping.S"
@@ -277,8 +279,8 @@ set_ivor:
ori r6, r6, swapper_pg_dir@l
lis r5, abatron_pteptrs@h
ori r5, r5, abatron_pteptrs@l
- lis r4, KERNELBASE@h
- ori r4, r4, KERNELBASE@l
+ lis r3, kernstart_virt_addr@ha
+ lwz r4, kernstart_virt_addr@l(r3)
stw r5, 0(r4) /* Save abatron_pteptrs at a fixed location */
stw r6, 0(r5)
@@ -1067,7 +1069,12 @@ __secondary_start:
mr r5,r25 /* phys kernel start */
rlwinm r5,r5,0,~0x3ffffff /* aligned 64M */
subf r4,r5,r4 /* memstart_addr - phys kernel start */
- li r5,0 /* no device tree */
+ lis r7,KERNELBASE@h
+ ori r7,r7,KERNELBASE@l
+ cmpw r20,r7 /* if kernstart_virt_addr != KERNELBASE, randomized */
+ beq 2f
+ li r4,0
+2: li r5,0 /* no device tree */
li r6,0 /* not boot cpu */
bl restore_to_as0