diff options
| author | Heinrich Schuchardt <xypron.glpk@gmx.de> | 2019-09-12 19:09:26 +0200 | 
|---|---|---|
| committer | Tom Rini <trini@konsulko.com> | 2019-10-11 15:33:27 -0400 | 
| commit | 57bbf44de6db8408e2b368475ca33dab3bab638a (patch) | |
| tree | 387c34a7361954ff60a26b27c3a4a13201077f08 /arch/arm | |
| parent | 100e75bbdbe3e2c02f004f7d26055ce57e6472eb (diff) | |
arm64: print instructions leading to exception
If an exception occurs in a loaded image and the relocation offset is
unknown, it is helpful to know the instructions pointed to by the
program counter. This patch adds the missing output.
A possible output is:
    Code: 910c4021 aa1303e0 f9400662 d63f0040 (e7f7defb)
The parentheses indicate the instruction causing the exception.
The output can be disassembled using scripts/decodecode:
echo 'Code: 90000360 9100b800 94002782 17ffff8f (e7f7defb)' | \
  ARCH=arm64 scripts/decodecode
Code: 90000360 9100b800 94002782 17ffff8f (e7f7defb)
All code
========
   0:   90000360    adrp    x0, 0x6c000
   4:   9100b800    add     x0, x0, #0x2e
   8:   94002782    bl      0x9e10
   c:   17ffff8f    b       0xfffffffffffffe48
  10:*  e7f7defb    .inst   0xe7f7defb ; undefined <-- trapping instruction
Code starting with the faulting instruction
===========================================
   0:   e7f7defb    .inst   0xe7f7defb ; undefined
We already have implemented the same for armv7.
For testing command 'exception undefined' can be used.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Diffstat (limited to 'arch/arm')
| -rw-r--r-- | arch/arm/lib/interrupts_64.c | 12 | 
1 files changed, 12 insertions, 0 deletions
| diff --git a/arch/arm/lib/interrupts_64.c b/arch/arm/lib/interrupts_64.c index 0bfdb8d93d2..a32a4b68684 100644 --- a/arch/arm/lib/interrupts_64.c +++ b/arch/arm/lib/interrupts_64.c @@ -30,6 +30,17 @@ static void show_efi_loaded_images(struct pt_regs *regs)  	efi_print_image_infos((void *)regs->elr);  } +static void dump_instr(struct pt_regs *regs) +{ +	u32 *addr = (u32 *)(regs->elr & ~3UL); +	int i; + +	printf("Code: "); +	for (i = -4; i < 1; i++) +		printf(i == 0 ? "(%08x) " : "%08x ", addr[i]); +	printf("\n"); +} +  void show_regs(struct pt_regs *regs)  {  	int i; @@ -44,6 +55,7 @@ void show_regs(struct pt_regs *regs)  		printf("x%-2d: %016lx x%-2d: %016lx\n",  		       i, regs->regs[i], i+1, regs->regs[i+1]);  	printf("\n"); +	dump_instr(regs);  }  /* | 
