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 --- arch/arm/lib/interrupts_64.c | 12 ++++++++++++ 1 file changed, 12 insertions(+)
diff --git a/arch/arm/lib/interrupts_64.c b/arch/arm/lib/interrupts_64.c index 0bfdb8d93d..a32a4b6868 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); }
/* -- 2.23.0