Re: [PATCH] Documentation: Mention why %p prints ptrval
From: Tobin C . Harding
Date: Thu Mar 22 2018 - 16:12:25 EST
On Thu, Mar 22, 2018 at 03:53:36PM +1030, Joel Stanley wrote:
> When debugging recent kernels, people will see '(ptrval)' but there
> isn't much information as to what that means. Briefly describe why it's
> there.
>
> Signed-off-by: Joel Stanley <joel@xxxxxxxxx>
> ---
> Documentation/core-api/printk-formats.rst | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/Documentation/core-api/printk-formats.rst b/Documentation/core-api/printk-formats.rst
> index 934559b3c130..eb30efdd2e78 100644
> --- a/Documentation/core-api/printk-formats.rst
> +++ b/Documentation/core-api/printk-formats.rst
> @@ -60,8 +60,8 @@ Plain Pointers
> Pointers printed without a specifier extension (i.e unadorned %p) are
> hashed to prevent leaking information about the kernel memory layout. This
> has the added benefit of providing a unique identifier. On 64-bit machines
> -the first 32 bits are zeroed. If you *really* want the address see %px
> -below.
> +the first 32 bits are zeroed. The kernel will print ``(ptrval)`` until it
> +gathers enough entropy. If you *really* want the address see %px below.
Acked-by: Tobin C. Harding <me@xxxxxxxx>
thanks,
Tobin.