[PATCH 3.16.y-ckt 194/216] arm64: Move cpu_resume into the text section

From: Luis Henriques
Date: Mon Jan 12 2015 - 13:37:36 EST


3.16.7-ckt4 -stable review patch. If anyone has any objections, please let me know.

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

From: Laura Abbott <lauraa@xxxxxxxxxxxxxx>

commit c3684fbb446501b48dec6677a6a9f61c215053de upstream.

The function cpu_resume currently lives in the .data section.
There's no reason for it to be there since we can use relative
instructions without a problem. Move a few cpu_resume data
structures out of the assembly file so the .data annotation
can be dropped completely and cpu_resume ends up in the read
only text section.

Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>
Reviewed-by: Mark Rutland <mark.rutland@xxxxxxx>
Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
Tested-by: Mark Rutland <mark.rutland@xxxxxxx>
Tested-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
Tested-by: Kees Cook <keescook@xxxxxxxxxxxx>
Acked-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
Signed-off-by: Laura Abbott <lauraa@xxxxxxxxxxxxxx>
Signed-off-by: Will Deacon <will.deacon@xxxxxxx>
[ luis: 3.16-stable prereq for
f43c27188a49 "arm64: kernel: fix __cpu_suspend mm switch on warm-boot" ]
Signed-off-by: Luis Henriques <luis.henriques@xxxxxxxxxxxxx>
---
arch/arm64/kernel/sleep.S | 36 ++++++------------------------------
arch/arm64/kernel/suspend.c | 4 ++--
2 files changed, 8 insertions(+), 32 deletions(-)

diff --git a/arch/arm64/kernel/sleep.S b/arch/arm64/kernel/sleep.S
index a564b440416a..ede186cdd452 100644
--- a/arch/arm64/kernel/sleep.S
+++ b/arch/arm64/kernel/sleep.S
@@ -147,14 +147,12 @@ cpu_resume_after_mmu:
ret
ENDPROC(cpu_resume_after_mmu)

- .data
ENTRY(cpu_resume)
bl el2_setup // if in EL2 drop to EL1 cleanly
#ifdef CONFIG_SMP
mrs x1, mpidr_el1
- adr x4, mpidr_hash_ptr
- ldr x5, [x4]
- add x8, x4, x5 // x8 = struct mpidr_hash phys address
+ adrp x8, mpidr_hash
+ add x8, x8, #:lo12:mpidr_hash // x8 = struct mpidr_hash phys address
/* retrieve mpidr_hash members to compute the hash */
ldr x2, [x8, #MPIDR_HASH_MASK]
ldp w3, w4, [x8, #MPIDR_HASH_SHIFTS]
@@ -164,14 +162,15 @@ ENTRY(cpu_resume)
#else
mov x7, xzr
#endif
- adr x0, sleep_save_sp
+ adrp x0, sleep_save_sp
+ add x0, x0, #:lo12:sleep_save_sp
ldr x0, [x0, #SLEEP_SAVE_SP_PHYS]
ldr x0, [x0, x7, lsl #3]
/* load sp from context */
ldr x2, [x0, #CPU_CTX_SP]
- adr x1, sleep_idmap_phys
+ adrp x1, sleep_idmap_phys
/* load physical address of identity map page table in x1 */
- ldr x1, [x1]
+ ldr x1, [x1, #:lo12:sleep_idmap_phys]
mov sp, x2
/*
* cpu_do_resume expects x0 to contain context physical address
@@ -180,26 +179,3 @@ ENTRY(cpu_resume)
bl cpu_do_resume // PC relative jump, MMU off
b cpu_resume_mmu // Resume MMU, never returns
ENDPROC(cpu_resume)
-
- .align 3
-mpidr_hash_ptr:
- /*
- * offset of mpidr_hash symbol from current location
- * used to obtain run-time mpidr_hash address with MMU off
- */
- .quad mpidr_hash - .
-/*
- * physical address of identity mapped page tables
- */
- .type sleep_idmap_phys, #object
-ENTRY(sleep_idmap_phys)
- .quad 0
-/*
- * struct sleep_save_sp {
- * phys_addr_t *save_ptr_stash;
- * phys_addr_t save_ptr_stash_phys;
- * };
- */
- .type sleep_save_sp, #object
-ENTRY(sleep_save_sp)
- .space SLEEP_SAVE_SP_SZ // struct sleep_save_sp
diff --git a/arch/arm64/kernel/suspend.c b/arch/arm64/kernel/suspend.c
index 13ad4dbb1615..3771b72b6569 100644
--- a/arch/arm64/kernel/suspend.c
+++ b/arch/arm64/kernel/suspend.c
@@ -126,8 +126,8 @@ int __cpu_suspend(unsigned long arg, int (*fn)(unsigned long))
return ret;
}

-extern struct sleep_save_sp sleep_save_sp;
-extern phys_addr_t sleep_idmap_phys;
+struct sleep_save_sp sleep_save_sp;
+phys_addr_t sleep_idmap_phys;

static int __init cpu_suspend_init(void)
{
--
2.1.4

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