Re: [PATCH v2 08/12] arm64: BTI: Decode BYTPE bits when printing PSTATE

From: Richard Henderson
Date: Fri Oct 11 2019 - 11:31:07 EST


On 10/10/19 2:44 PM, Dave Martin wrote:
> #define PSR_IL_BIT (1 << 20)
> -#define PSR_BTYPE_CALL (2 << PSR_BTYPE_SHIFT)
> +
> +/* Convenience names for the values of PSTATE.BTYPE */
> +#define PSR_BTYPE_NONE (0b00 << PSR_BTYPE_SHIFT)
> +#define PSR_BTYPE_JC (0b01 << PSR_BTYPE_SHIFT)
> +#define PSR_BTYPE_C (0b10 << PSR_BTYPE_SHIFT)
> +#define PSR_BTYPE_J (0b11 << PSR_BTYPE_SHIFT)

It'd be nice to sort this patch earlier, so that ...

> diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c
> index 4a3bd32..452ac5b 100644
> --- a/arch/arm64/kernel/signal.c
> +++ b/arch/arm64/kernel/signal.c
> @@ -732,7 +732,7 @@ static void setup_return(struct pt_regs *regs, struct k_sigaction *ka,
>
> if (system_supports_bti()) {
> regs->pstate &= ~PSR_BTYPE_MASK;
> - regs->pstate |= PSR_BTYPE_CALL;
> + regs->pstate |= PSR_BTYPE_C;
> }
>
> if (ka->sa.sa_flags & SA_RESTORER)

... setup_return does not need to be adjusted a second time.

I don't see any other conflicts vs patch 5.


r~