Re: [PATCH] ARM: fault: Add "cut here" line for prefetch aborts

From: Ard Biesheuvel
Date: Tue Jan 23 2024 - 08:46:36 EST


On Tue, 23 Jan 2024 at 02:12, Kees Cook <keescook@xxxxxxxxxxxx> wrote:
>
> The common pattern in arm is to emit a "8<--- cut here ---" line for
> faults, but it was missing for do_PrefetchAbort(). Add it.
>
> Cc: "Russell King (Oracle)" <rmk+kernel@xxxxxxxxxxxxxxx>
> Cc: Ard Biesheuvel <ardb@xxxxxxxxxx>
> Cc: Wang Kefeng <wangkefeng.wang@xxxxxxxxxx>
> Cc: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>

Acked-by: Ard Biesheuvel <ardb@xxxxxxxxxx>

> ---
> arch/arm/mm/fault.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
> index e96fb40b9cc3..e804432e905e 100644
> --- a/arch/arm/mm/fault.c
> +++ b/arch/arm/mm/fault.c
> @@ -586,6 +586,7 @@ do_PrefetchAbort(unsigned long addr, unsigned int ifsr, struct pt_regs *regs)
> if (!inf->fn(addr, ifsr | FSR_LNX_PF, regs))
> return;
>
> + pr_alert("8<--- cut here ---\n");
> pr_alert("Unhandled prefetch abort: %s (0x%03x) at 0x%08lx\n",
> inf->name, ifsr, addr);
>
> --
> 2.34.1
>