我正在尝试理解我遇到的ARM异常的原因。这经常发生在系统启动过程中,可能会以几种不同的方式出现。
其中最简单的一种是以下情况:
0x8004e810 in ti_sysbios_family_arm_a8_intcps_Hwi_vectors ()
#0 0x8004e810 in ti_sysbios_family_arm_a8_intcps_Hwi_vectors ()
#1 0x80002f04 in ti_sysbios_family_arm_exc_Exception_excHandlerDataAsm(int0_t) ()
at /home/rnd_share/sysbios/bios_6_51_00_15/packages/ti/sysbios/family/arm/exc/Exception_asm_gnu.asm:103
Backtrace stopped: previous frame identical to this frame (corrupt stack?)
r0 0x20000197 536871319
r1 0x20000197 536871319
r2 0x20000197 536871319
r3 0x20000197 536871319
r4 0x20000197 536871319
r5 0x6 6
r6 0x80000024 2147483684
r7 0x80007a0c 2147514892
r8 0x8004f0a8 2147807400
r9 0x80041340 2147750720
r10 0x80040a3c 2147748412
r11 0xffffffff 4294967295
r12 0x20000197 536871319
sp 0x7fffff88 0x7fffff88
lr 0x80002f04 2147495684
pc 0x8004e810 0x8004e810 <ti_sysbios_family_arm_a8_intcps_Hwi_vectors+16>
cpsr 0x20000197 536871319
PC = 8004E810, CPSR = 20000197 (ABORT mode, ARM IRQ dis.)
R0 = 20000197, R1 = 20000197, R2 = 20000197, R3 = 20000197
R4 = 20000197, R5 = 00000006, R6 = 80000024, R7 = 80007A0C
USR: R8 =8004F0A8, R9 =80041340, R10=80040A3C, R11 =FFFFFFFF, R12 =20000197
R13=80212590, R14=80040A3C
FIQ: R8 =AEE1D6FA, R9 =C07BA930, R10=1B0B137A, R11 =7EC3F1DF, R12 =2000019F
R13=80065CF8, R14=00000000, SPSR=00000000
SVC: R13=4030CB20, R14=00022071, SPSR=00000000
ABT: R13=7FFFFF88, R14=80002F04, SPSR=20000197
IRQ: R13=F4ADFD8A, R14=80041020, SPSR=8000011F
UND: R13=80085CF8, R14=ED0F7EF1, SPSR=00000000
(gdb) frame
#0 0x8004e810 in ti_sysbios_family_arm_a8_intcps_Hwi_vectors ()
(gdb) frame 1
#1 0x80002f04 in ti_sysbios_family_arm_exc_Exception_excHandlerDataAsm(int0_t) ()
at /home/rnd_share/sysbios/bios_6_51_00_15/packages/ti/sysbios/family/arm/exc/Exception_asm_gnu.asm:103
103 mrc p15, #0, r12, c5, c0, #0 @ read DFSR into r12
(gdb) list
98 .func ti_sysbios_family_arm_exc_Exception_excHandlerDataAsm__I
99
100 ti_sysbios_family_arm_exc_Exception_excHandlerDataAsm__I:
101 stmfd sp!, {r0-r12} @ save r4-r12 while we're at it
102
103 mrc p15, #0, r12, c5, c0, #0 @ read DFSR into r12
104 stmfd sp!, {r12} @ save DFSR
105 mrc p15, #0, r12, c5, c0, #1 @ read IFSR into r12
106 stmfd sp!, {r12} @ save DFSR
107 mrc p15, #0, r12, c6, c0, #0 @ read DFAR into r12
(gdb) monitor cp15 6 0 0 0
Reading CP15 register (6,0,0,0 = 0x7FFFFF54)
我的理解是,在第一帧中可以看到正在进行的异常,它试图将寄存器保存到堆栈中:
101 stmfd sp!, {r0-r12} @ 一边保存 r4-r12
但是,在以下位置,堆栈指针不正确:
ABT: R13=7FFFFF88
我不明白两个问题:
- 在 ABT 和 IRQ 上下文中,这种 SP 值的原因是什么?
- 实际上在第 0 帧中有什么? 换句话说,当 Cortex 在异常处理程序中时,如何对数据异常做出反应?
这个设备通常正常启动,这种情况在10次启动中会发生3次。 它从调试器启动时从未发生过,只有在发布版本中从引导加载程序启动时才会发生。
initcall_debug
和其他kconfig值来检查内存问题。 - artless noise