4.7-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Ard Biesheuvel <[email protected]>

commit bc9f3d7788a88d080a30599bde68f383daf8f8a5 upstream.

Literal loads of virtual addresses are subject to runtime relocation when
CONFIG_RELOCATABLE=y, and given that the relocation routines run with the
MMU and caches enabled, literal loads of relocated values performed with
the MMU off are not guaranteed to return the latest value unless the
memory covering the literal is cleaned to the PoC explicitly.

So defer the literal load until after the MMU has been enabled, just like
we do for primary_switch() and secondary_switch() in head.S.

Fixes: 1e48ef7fcc37 ("arm64: add support for building vmlinux as a relocatable 
PIE binary")
Signed-off-by: Ard Biesheuvel <[email protected]>
Acked-by: Mark Rutland <[email protected]>
Signed-off-by: Catalin Marinas <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 arch/arm64/kernel/sleep.S |   10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

--- a/arch/arm64/kernel/sleep.S
+++ b/arch/arm64/kernel/sleep.S
@@ -101,12 +101,20 @@ ENTRY(cpu_resume)
        bl      el2_setup               // if in EL2 drop to EL1 cleanly
        /* enable the MMU early - so we can access sleep_save_stash by va */
        adr_l   lr, __enable_mmu        /* __cpu_setup will return here */
-       ldr     x27, =_cpu_resume       /* __enable_mmu will branch here */
+       adr_l   x27, _resume_switched   /* __enable_mmu will branch here */
        adrp    x25, idmap_pg_dir
        adrp    x26, swapper_pg_dir
        b       __cpu_setup
 ENDPROC(cpu_resume)
 
+       .pushsection    ".idmap.text", "ax"
+_resume_switched:
+       ldr     x8, =_cpu_resume
+       br      x8
+ENDPROC(_resume_switched)
+       .ltorg
+       .popsection
+
 ENTRY(_cpu_resume)
        mrs     x1, mpidr_el1
        adrp    x8, mpidr_hash


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