[ Upstream commit 56c46bba9bbfe229b4472a5be313c44c5b714a39 ]
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 ruscur@russell.cc [mpe: Fix it to work on BE by using DOTSYM()] Signed-off-by: Michael Ellerman mpe@ellerman.id.au Signed-off-by: Sasha Levin sashal@kernel.org --- 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 ff8511d6d8ead..4f2e18266e34a 100644 --- a/arch/powerpc/kernel/head_64.S +++ b/arch/powerpc/kernel/head_64.S @@ -961,7 +961,9 @@ 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, DOTSYM(early_setup)) + mtctr r12 + bctrl /* also sets r13 and SPRG_PACA */
LOAD_REG_ADDR(r3, start_here_common) ld r4,PACAKMSR(r13)