[PATCH 2/2] ARM: replace BSYM() with badr assembly macro
Russell King
rmk+kernel at arm.linux.org.uk
Fri May 8 09:08:47 PDT 2015
BSYM() was invented to allow us to work around a problem with the
assembler, where local symbols resolved by the assembler for the 'adr'
instruction did not take account of their ISA.
Since we don't want BSYM() used elsewhere, replace BSYM() with a new
macro 'badr', which is like the 'adr' pseudo-op, but with the BSYM()
mechanics integrated into it. This ensures that the BSYM()-ification
is only used in conjunction with 'adr'.
Signed-off-by: Russell King <rmk+kernel at arm.linux.org.uk>
---
arch/arm/boot/compressed/head.S | 4 ++--
arch/arm/common/mcpm_head.S | 2 +-
arch/arm/include/asm/assembler.h | 17 ++++++++++++++++-
arch/arm/include/asm/entry-macro-multi.S | 4 ++--
arch/arm/include/asm/unified.h | 2 --
arch/arm/kernel/entry-armv.S | 12 ++++++------
arch/arm/kernel/entry-common.S | 6 +++---
arch/arm/kernel/entry-ftrace.S | 2 +-
arch/arm/kernel/head-nommu.S | 6 +++---
arch/arm/kernel/head.S | 8 ++++----
arch/arm/kernel/sleep.S | 2 +-
arch/arm/lib/call_with_stack.S | 2 +-
arch/arm/mm/proc-v7m.S | 2 +-
13 files changed, 41 insertions(+), 28 deletions(-)
diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S
index 2c45b5709fa4..06e983f59980 100644
--- a/arch/arm/boot/compressed/head.S
+++ b/arch/arm/boot/compressed/head.S
@@ -130,7 +130,7 @@ start:
.endr
ARM( mov r0, r0 )
ARM( b 1f )
- THUMB( adr r12, BSYM(1f) )
+ THUMB( badr r12, 1f )
THUMB( bx r12 )
.word _magic_sig @ Magic numbers to help the loader
@@ -447,7 +447,7 @@ dtb_check_done:
bl cache_clean_flush
- adr r0, BSYM(restart)
+ badr r0, restart
add r0, r0, r6
mov pc, r0
diff --git a/arch/arm/common/mcpm_head.S b/arch/arm/common/mcpm_head.S
index e02db4b81a66..08b3bb9bc6a2 100644
--- a/arch/arm/common/mcpm_head.S
+++ b/arch/arm/common/mcpm_head.S
@@ -49,7 +49,7 @@
ENTRY(mcpm_entry_point)
ARM_BE8(setend be)
- THUMB( adr r12, BSYM(1f) )
+ THUMB( badr r12, 1f )
THUMB( bx r12 )
THUMB( .thumb )
1:
diff --git a/arch/arm/include/asm/assembler.h b/arch/arm/include/asm/assembler.h
index 186270b3e194..4abe57279c66 100644
--- a/arch/arm/include/asm/assembler.h
+++ b/arch/arm/include/asm/assembler.h
@@ -178,6 +178,21 @@
.endm
/*
+ * Assembly version of "adr rd, BSYM(sym)". This should only be used to
+ * reference local symbols in the same assembly file which are to be
+ * resolved by the assembler. Other usage is undefined.
+ */
+ .irp c,,eq,ne,cs,cc,mi,pl,vs,vc,hi,ls,ge,lt,gt,le,hs,lo
+ .macro badr\c, rd, sym
+#ifdef CONFIG_THUMB2_KERNEL
+ adr\c \rd, \sym + 1
+#else
+ adr\c \rd, \sym
+#endif
+ .endm
+ .endr
+
+/*
* Get current thread_info.
*/
.macro get_thread_info, rd
@@ -326,7 +341,7 @@
THUMB( orr \reg , \reg , #PSR_T_BIT )
bne 1f
orr \reg, \reg, #PSR_A_BIT
- adr lr, BSYM(2f)
+ badr lr, 2f
msr spsr_cxsf, \reg
__MSR_ELR_HYP(14)
__ERET
diff --git a/arch/arm/include/asm/entry-macro-multi.S b/arch/arm/include/asm/entry-macro-multi.S
index 469a2b30fa27..609184f522ee 100644
--- a/arch/arm/include/asm/entry-macro-multi.S
+++ b/arch/arm/include/asm/entry-macro-multi.S
@@ -10,7 +10,7 @@
@
@ routine called with r0 = irq number, r1 = struct pt_regs *
@
- adrne lr, BSYM(1b)
+ badrne lr, 1b
bne asm_do_IRQ
#ifdef CONFIG_SMP
@@ -23,7 +23,7 @@
ALT_SMP(test_for_ipi r0, r2, r6, lr)
ALT_UP_B(9997f)
movne r1, sp
- adrne lr, BSYM(1b)
+ badrne lr, 1b
bne do_IPI
#endif
9997:
diff --git a/arch/arm/include/asm/unified.h b/arch/arm/include/asm/unified.h
index 200f9a7cd623..a91ae499614c 100644
--- a/arch/arm/include/asm/unified.h
+++ b/arch/arm/include/asm/unified.h
@@ -45,7 +45,6 @@
#define THUMB(x...) x
#ifdef __ASSEMBLY__
#define W(instr) instr.w
-#define BSYM(sym) sym + 1
#else
#define WASM(instr) #instr ".w"
#endif
@@ -59,7 +58,6 @@
#define THUMB(x...)
#ifdef __ASSEMBLY__
#define W(instr) instr
-#define BSYM(sym) sym
#else
#define WASM(instr) #instr
#endif
diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S
index 570306c49406..f8f7398c74c2 100644
--- a/arch/arm/kernel/entry-armv.S
+++ b/arch/arm/kernel/entry-armv.S
@@ -40,7 +40,7 @@
#ifdef CONFIG_MULTI_IRQ_HANDLER
ldr r1, =handle_arch_irq
mov r0, sp
- adr lr, BSYM(9997f)
+ badr lr, 9997f
ldr pc, [r1]
#else
arch_irq_handler_default
@@ -273,7 +273,7 @@ __und_svc:
str r4, [sp, #S_PC]
orr r0, r9, r0, lsl #16
#endif
- adr r9, BSYM(__und_svc_finish)
+ badr r9, __und_svc_finish
mov r2, r4
bl call_fpe
@@ -469,7 +469,7 @@ __und_usr:
@ instruction, or the more conventional lr if we are to treat
@ this as a real undefined instruction
@
- adr r9, BSYM(ret_from_exception)
+ badr r9, ret_from_exception
@ IRQs must be enabled before attempting to read the instruction from
@ user space since that could cause a page/translation fault if the
@@ -486,7 +486,7 @@ __und_usr:
@ r2 = PC value for the following instruction (:= regs->ARM_pc)
@ r4 = PC value for the faulting instruction
@ lr = 32-bit undefined instruction function
- adr lr, BSYM(__und_usr_fault_32)
+ badr lr, __und_usr_fault_32
b call_fpe
__und_usr_thumb:
@@ -522,7 +522,7 @@ ARM_BE8(rev16 r0, r0) @ little endian instruction
add r2, r2, #2 @ r2 is PC + 2, make it PC + 4
str r2, [sp, #S_PC] @ it's a 2x16bit instr, update
orr r0, r0, r5, lsl #16
- adr lr, BSYM(__und_usr_fault_32)
+ badr lr, __und_usr_fault_32
@ r0 = the two 16-bit Thumb instructions which caused the exception
@ r2 = PC value for the following Thumb instruction (:= regs->ARM_pc)
@ r4 = PC value for the first 16-bit Thumb instruction
@@ -716,7 +716,7 @@ __und_usr_fault_32:
__und_usr_fault_16:
mov r1, #2
1: mov r0, sp
- adr lr, BSYM(ret_from_exception)
+ badr lr, ret_from_exception
b __und_fault
ENDPROC(__und_usr_fault_32)
ENDPROC(__und_usr_fault_16)
diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S
index f8ccc21fa032..6ab159384667 100644
--- a/arch/arm/kernel/entry-common.S
+++ b/arch/arm/kernel/entry-common.S
@@ -88,7 +88,7 @@ ENTRY(ret_from_fork)
bl schedule_tail
cmp r5, #0
movne r0, r4
- adrne lr, BSYM(1f)
+ badrne lr, 1f
retne r5
1: get_thread_info tsk
b ret_slow_syscall
@@ -196,7 +196,7 @@ local_restart:
bne __sys_trace
cmp scno, #NR_syscalls @ check upper syscall limit
- adr lr, BSYM(ret_fast_syscall) @ return address
+ badr lr, ret_fast_syscall @ return address
ldrcc pc, [tbl, scno, lsl #2] @ call sys_* routine
add r1, sp, #S_OFF
@@ -231,7 +231,7 @@ __sys_trace:
add r0, sp, #S_OFF
bl syscall_trace_enter
- adr lr, BSYM(__sys_trace_return) @ return address
+ badr lr, __sys_trace_return @ return address
mov scno, r0 @ syscall number (possibly new)
add r1, sp, #S_R0 + S_OFF @ pointer to regs
cmp scno, #NR_syscalls @ check upper syscall limit
diff --git a/arch/arm/kernel/entry-ftrace.S b/arch/arm/kernel/entry-ftrace.S
index fe57c73e70a4..c73c4030ca5d 100644
--- a/arch/arm/kernel/entry-ftrace.S
+++ b/arch/arm/kernel/entry-ftrace.S
@@ -87,7 +87,7 @@
1: mcount_get_lr r1 @ lr of instrumented func
mcount_adjust_addr r0, lr @ instrumented function
- adr lr, BSYM(2f)
+ badr lr, 2f
mov pc, r2
2: mcount_exit
.endm
diff --git a/arch/arm/kernel/head-nommu.S b/arch/arm/kernel/head-nommu.S
index 84da14b7cd04..c9660167ef1a 100644
--- a/arch/arm/kernel/head-nommu.S
+++ b/arch/arm/kernel/head-nommu.S
@@ -46,7 +46,7 @@ ENTRY(stext)
.arm
ENTRY(stext)
- THUMB( adr r9, BSYM(1f) ) @ Kernel is always entered in ARM.
+ THUMB( badr r9, 1f ) @ Kernel is always entered in ARM.
THUMB( bx r9 ) @ If this is a Thumb-2 kernel,
THUMB( .thumb ) @ switch to Thumb now.
THUMB(1: )
@@ -79,7 +79,7 @@ ENTRY(stext)
#endif
ldr r13, =__mmap_switched @ address to jump to after
@ initialising sctlr
- adr lr, BSYM(1f) @ return (PIC) address
+ badr lr, 1f @ return (PIC) address
ldr r12, [r10, #PROCINFO_INITFUNC]
add r12, r12, r10
ret r12
@@ -115,7 +115,7 @@ ENTRY(secondary_startup)
bl __setup_mpu @ Initialize the MPU
#endif
- adr lr, BSYM(__after_proc_init) @ return address
+ badr lr, __after_proc_init @ return address
mov r13, r12 @ __secondary_switched address
ldr r12, [r10, #PROCINFO_INITFUNC]
add r12, r12, r10
diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S
index 7304b4c44b52..1eecd57453be 100644
--- a/arch/arm/kernel/head.S
+++ b/arch/arm/kernel/head.S
@@ -80,7 +80,7 @@
ENTRY(stext)
ARM_BE8(setend be ) @ ensure we are in BE8 mode
- THUMB( adr r9, BSYM(1f) ) @ Kernel is always entered in ARM.
+ THUMB( badr r9, 1f ) @ Kernel is always entered in ARM.
THUMB( bx r9 ) @ If this is a Thumb-2 kernel,
THUMB( .thumb ) @ switch to Thumb now.
THUMB(1: )
@@ -148,7 +148,7 @@ ENTRY(stext)
*/
ldr r13, =__mmap_switched @ address to jump to after
@ mmu has been enabled
- adr lr, BSYM(1f) @ return (PIC) address
+ badr lr, 1f @ return (PIC) address
#ifdef CONFIG_ARM_LPAE
mov r5, #0 @ high TTBR0
mov r8, r4, lsr #12 @ TTBR1 is swapper_pg_dir pfn
@@ -364,7 +364,7 @@ __turn_mmu_on_loc:
.text
ENTRY(secondary_startup_arm)
.arm
- THUMB( adr r9, BSYM(1f) ) @ Kernel is entered in ARM.
+ THUMB( badr r9, 1f ) @ Kernel is entered in ARM.
THUMB( bx r9 ) @ If this is a Thumb-2 kernel,
THUMB( .thumb ) @ switch to Thumb now.
THUMB(1: )
@@ -400,7 +400,7 @@ ENTRY(secondary_startup)
add r3, r7, lr
ldrd r4, [r3, #0] @ get secondary_data.pgdir
ldr r8, [r3, #8] @ get secondary_data.swapper_pg_dir
- adr lr, BSYM(__enable_mmu) @ return address
+ badr lr, __enable_mmu @ return address
mov r13, r12 @ __secondary_switched address
ldr r12, [r10, #PROCINFO_INITFUNC]
add r12, r12, r10 @ initialise processor
diff --git a/arch/arm/kernel/sleep.S b/arch/arm/kernel/sleep.S
index 7d37bfc50830..76bb3128e135 100644
--- a/arch/arm/kernel/sleep.S
+++ b/arch/arm/kernel/sleep.S
@@ -81,7 +81,7 @@ ENTRY(__cpu_suspend)
mov r1, r4 @ size of save block
add r0, sp, #8 @ pointer to save block
bl __cpu_suspend_save
- adr lr, BSYM(cpu_suspend_abort)
+ badr lr, cpu_suspend_abort
ldmfd sp!, {r0, pc} @ call suspend fn
ENDPROC(__cpu_suspend)
.ltorg
diff --git a/arch/arm/lib/call_with_stack.S b/arch/arm/lib/call_with_stack.S
index ed1a421813cb..bf3a40889205 100644
--- a/arch/arm/lib/call_with_stack.S
+++ b/arch/arm/lib/call_with_stack.S
@@ -35,7 +35,7 @@ ENTRY(call_with_stack)
mov r2, r0
mov r0, r1
- adr lr, BSYM(1f)
+ badr lr, 1f
ret r2
1: ldr lr, [sp]
diff --git a/arch/arm/mm/proc-v7m.S b/arch/arm/mm/proc-v7m.S
index e08e1f2bab76..67d9209077c6 100644
--- a/arch/arm/mm/proc-v7m.S
+++ b/arch/arm/mm/proc-v7m.S
@@ -98,7 +98,7 @@ __v7m_setup:
str r5, [r0, V7M_SCB_SHPR3] @ set PendSV priority
@ SVC to run the kernel in this mode
- adr r1, BSYM(1f)
+ badr r1, 1f
ldr r5, [r12, #11 * 4] @ read the SVC vector entry
str r1, [r12, #11 * 4] @ write the temporary SVC vector entry
mov r6, lr @ save LR
--
1.8.3.1
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