ARM: make kernel oops easier to read

We don't need the offset for the first function name in each backtrace
entry; this needlessly consumes screen space.  This is virtually always
the first or second instruction in the called function.

Also, recognise stmfd instructions which include r10 as a valid stack
saving instruction, and when dumping the registers, dump six registers
per line rather than five, and fix the wrapping.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 10 insertions, 10 deletions

diff --git a/arch/arm/lib/backtrace.S b/arch/arm/lib/backtrace.S
index cd07b5814c23..4102be617fce 100644
--- a/arch/arm/lib/backtrace.S
+++ b/arch/arm/lib/backtrace.S
@@ -80,14 +80,14 @@ for_each_frame:	tst	frame, mask		@ Check for address exceptions
 
                 ldr     r1, [sv_pc, #-4]        @ if stmfd sp!, {args} exists,
                 ldr     r3, .Ldsi+4
-                teq     r3, r1, lsr #10
+                teq     r3, r1, lsr #11
                 ldreq   r0, [frame, #-8]        @ get sp
                 subeq   r0, r0, #4              @ point at the last arg
                 bleq    .Ldumpstm               @ dump saved registers
 
 1004:           ldr     r1, [sv_pc, #0]         @ if stmfd sp!, {..., fp, ip, lr, pc}
                 ldr     r3, .Ldsi               @ instruction exists,
-                teq     r3, r1, lsr #10
+                teq     r3, r1, lsr #11
                 subeq   r0, frame, #16
                 bleq    .Ldumpstm               @ dump saved registers
 
@@ -128,11 +128,11 @@ ENDPROC(c_backtrace)
                 beq     2f
                 add     r7, r7, #1
                 teq     r7, #6
-                moveq   r7, #1
-                moveq   r1, #'\n'
-                movne   r1, #' '
-                ldr     r3, [stack], #-4
-                mov     r2, reg
+                moveq   r7, #0
+                adr     r3, .Lcr
+                addne   r3, r3, #1              @ skip newline
+                ldr     r2, [stack], #-4
+                mov     r1, reg
                 adr     r0, .Lfp
                 bl      printk
 2:              subs    reg, reg, #1
@@ -142,11 +142,11 @@ ENDPROC(c_backtrace)
                 blne    printk
                 ldmfd   sp!, {instr, reg, stack, r7, pc}
 
-.Lfp:           .asciz  "%cr%d:%08x"
+.Lfp:           .asciz  " r%d:%08x%s"
 .Lcr:           .asciz  "\n"
 .Lbad:          .asciz  "Backtrace aborted due to bad frame pointer <%p>\n"
                 .align
-.Ldsi:          .word   0xe92dd800 >> 10        @ stmfd sp!, {... fp, ip, lr, pc}
-                .word   0xe92d0000 >> 10        @ stmfd sp!, {}
+.Ldsi:          .word   0xe92dd800 >> 11        @ stmfd sp!, {... fp, ip, lr, pc}
+                .word   0xe92d0000 >> 11        @ stmfd sp!, {}
 
 #endif