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>

diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c
index 7940241f0576b0db1cc0a749e449c7faf492518a..a55a142678706e4954df5338bfb613ae8fc177f3 100644 (file)
--- a/arch/arm/kernel/traps.c
+++ b/arch/arm/kernel/traps.c
@@ -56,7 +56,7 @@ static void dump_mem(const char *, const char *, unsigned long, unsigned long);
 void dump_backtrace_entry(unsigned long where, unsigned long from, unsigned long frame)
 {
 #ifdef CONFIG_KALLSYMS
-       printk("[<%08lx>] (%pS) from [<%08lx>] (%pS)\n", where, (void *)where, from, (void *)from);
+       printk("[<%08lx>] (%ps) from [<%08lx>] (%pS)\n", where, (void *)where, from, (void *)from);
 #else
        printk("Function entered at [<%08lx>] from [<%08lx>]\n", where, from);
 #endif

diff --git a/arch/arm/lib/backtrace.S b/arch/arm/lib/backtrace.S
index cd07b5814c2304f0908342b04291af09388790b7..4102be617fce0644434e3aa7f7fec65c09fcb5e7 100644 (file)
--- 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