[PATCH] riscv: Increase stack size under KASAN

[Palmer Dabbelt]

On Mon, 14 Mar 2022 02:06:52 PDT (-0700), dvyukov at google.com wrote:
> KASAN requires more stack space because of compiler instrumentation.
> Increase stack size as other arches do.
>
> Signed-off-by: Dmitry Vyukov <dvyukov at google.com>
> Reported-by: syzbot+0600986d88e2d4d7ebb8 at syzkaller.appspotmail.com
> Cc: linux-riscv at lists.infradead.org
> Cc: kasan-dev at googlegroups.com
> ---
>  arch/riscv/include/asm/thread_info.h | 10 ++++++++--
>  1 file changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/arch/riscv/include/asm/thread_info.h b/arch/riscv/include/asm/thread_info.h
> index 60da0dcacf145..74d888c8d631a 100644
> --- a/arch/riscv/include/asm/thread_info.h
> +++ b/arch/riscv/include/asm/thread_info.h
> @@ -11,11 +11,17 @@
>  #include <asm/page.h>
>  #include <linux/const.h>
>
> +#ifdef CONFIG_KASAN
> +#define KASAN_STACK_ORDER 1
> +#else
> +#define KASAN_STACK_ORDER 0
> +#endif
> +
>  /* thread information allocation */
>  #ifdef CONFIG_64BIT
> -#define THREAD_SIZE_ORDER	(2)
> +#define THREAD_SIZE_ORDER	(2 + KASAN_STACK_ORDER)
>  #else
> -#define THREAD_SIZE_ORDER	(1)
> +#define THREAD_SIZE_ORDER	(1 + KASAN_STACK_ORDER)
>  #endif
>  #define THREAD_SIZE		(PAGE_SIZE << THREAD_SIZE_ORDER)
>
>
> base-commit: 0966d385830de3470b7131db8e86c0c5bc9c52dc

Thanks, this is on for-next (there's no fixes right now, I'm still 
collecting stuff for this merge window).