From: Joel Stanley Date: Thu, 22 Mar 2018 05:23:36 +0000 (+1030) Subject: Documentation: Mention why %p prints ptrval X-Git-Tag: v4.17-rc1~149^2~8 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=156383b190cd1b240a4c8636c9ce7a2a42938b24;p=linux.git Documentation: Mention why %p prints ptrval 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 Acked-by: Tobin C. Harding Signed-off-by: Jonathan Corbet --- 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. Symbols/Function Pointers -------------------------