Re: [PATCH] mm/vmalloc: Use %p for pointer formatting

[Sebastian Andrzej Siewior <bigeasy@linutronix.de>]

On 2026-09-18 13:05:41 [-0700], Andrew Morton wrote:
> On Fri, 18 Sep 2026 12:50:13 +0200 Sebastian Andrzej Siewior <bigeasy@linutronix.de> wrote:
> 
> > Commit 45ec16908e84e ("mm: use %pK for /proc/vmallocinfo") introduced
> > the %pK in order not to leak kernel pointers.
> > Since commit ad67b74d2469d ("printk: hash addresses printed with
> > %p") pointers are hashed by default and the behaviour can be controller
> > by `hash_pointers' boot argument.
> > The policy on %p is to not introduce new ones.
> > Removing %pK makes it possible to remove its handling from the library.
> > 
> > Looking at the output, having the pointer in the output makes it
> > possible to distinguish the individual entries.
> > 
> > Use %p instead %pK.
> 
> Fair enough.
> 
> I added this (important) info to the changelog.  Please confirm its
> accurary.
> 
> : /proc/vmallocinfo has mode 0400, so this change doesn't make kernel
> : pointer information available to unprivileged userspace.

Confirmed.
[%p is hashed by default so things shouldn't change here.]

Sebastian