From: Russell Currey Date: Wed, 27 Mar 2019 03:35:54 +0000 (+1100) Subject: powerpc/64: Fix booting large kernels with STRICT_KERNEL_RWX X-Git-Tag: v5.0.20~198 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8c54b4088fc29a83aa262a132d36739cedfcb11e;p=thirdparty%2Fkernel%2Fstable.git powerpc/64: Fix booting large kernels with STRICT_KERNEL_RWX [ 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 [mpe: Fix it to work on BE by using DOTSYM()] Signed-off-by: Michael Ellerman Signed-off-by: Sasha Levin --- diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S index 4898e9491a1cd..9168a247e24ff 100644 --- a/arch/powerpc/kernel/head_64.S +++ b/arch/powerpc/kernel/head_64.S @@ -970,7 +970,9 @@ 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)