# \[PATCH\] powerpc/64: Fix booting large kernels with STRICT\_KERNEL\_RWX - From: Russell Currey \ - Date: 2019-03-27 03:38:02 - List: linuxppc-dev - Page: https://ratatoskr.run/linuxppc-dev/2019/03/9509135 - Thread: https://ratatoskr.run/linuxppc-dev/2019/03/9509135/t.md ```text With STRICT_KERNEL_RWX enabled anything marked __init is placed at a 16M boundary. This is necessary so that it can be repurposed later with different permissions. However, in kernels with text larger than 16M, this pushes early_setup past 32M, incapable of being reached by the branch instruction. Fix this by setting the CTR and branching there instead. Fixes: 1e0fc9d1eb2b ("powerpc/Kconfig: Enable STRICT_KERNEL_RWX for some configs") Signed-off-by: Russell Currey --- arch/powerpc/kernel/head_64.S | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S index 3fad8d499767..c2b53febadd9 100644 --- a/arch/powerpc/kernel/head_64.S +++ b/arch/powerpc/kernel/head_64.S @@ -968,7 +968,9 @@ start_here_multiplatform: /* Restore parameters passed from prom_init/kexec */ mr r3,r31 - bl early_setup /* also sets r13 and SPRG_PACA */ + LOAD_REG_ADDR(r12, early_setup) + mtctr r12 + bctrl /* also sets r13 and SPRG_PACA */ LOAD_REG_ADDR(r3, start_here_common) ld r4,PACAKMSR(r13) -- 2.21.0 ```