From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 71071C982DD for ; Fri, 18 Sep 2026 20:05:46 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 659FF6B0093; Fri, 18 Sep 2026 16:05:45 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 60B386B0095; Fri, 18 Sep 2026 16:05:45 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 523366B0096; Fri, 18 Sep 2026 16:05:45 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 307AE6B0093 for ; Fri, 18 Sep 2026 16:05:45 -0400 (EDT) Received: from smtpin09.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 715FAA630B for ; Fri, 18 Sep 2026 20:05:44 +0000 (UTC) X-FDA: 85227963408.09.F752478 Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by imf16.hostedemail.com (Postfix) with ESMTP id 9DB7C180004 for ; Fri, 18 Sep 2026 20:05:42 +0000 (UTC) Authentication-Results: imf16.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=wZ9w+V9p; dmarc=none; spf=pass (imf16.hostedemail.com: domain of akpm@linux-foundation.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1789761942; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=/9eCkd+/q2YFDNvV3tExteb4O3KYk7MFOgoJKuvoKVs=; b=gxRnG6D1rA5GwuorEd9kKCn1O4bRBTPkNKPPkVHMl0rx6Z6ochxupLjMQ+u0MXgC1RFodA /i/USvusacA8g3THM6D9xmZWle9Cxdx36pE/PlQLRmzhxdlkpGtlrGyEvvOj8ossW9+nWZ yBCkm3qT127p5JKvIuf5dIUi0kDojZw= ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1789761942; b=opd080hRZjKq9G4BwojImBglmLx/Irx27K4KRrq4tLudDJCAb5+4XHUL2/8OMqh8noRpep M+qcz70hMbwRhHaEb1B91JIX3cPK3zDbma9k/UCfZljysnE3i6z0k7I+5MkKQ4a4U0iFC+ G96yCcD5deAYexKtzmguLUjNU1npXh4= ARC-Authentication-Results: i=1; imf16.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=wZ9w+V9p; dmarc=none; spf=pass (imf16.hostedemail.com: domain of akpm@linux-foundation.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id CE07B438DE; Fri, 18 Sep 2026 20:05:41 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9BB771F000FF; Fri, 18 Sep 2026 20:05:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1789761941; bh=/9eCkd+/q2YFDNvV3tExteb4O3KYk7MFOgoJKuvoKVs=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=wZ9w+V9pcKZq22sMAtKM9V1siY/Ju7L1ZFx6jrTHphsJW9YGHAj81/7DhlOwXgsbW C7tkV2qHpO6L2Zm61Pdlw8hUZ0qEA5HmK7jx1/RyqY+movb/GMJBItRZx3Hh5+e2ap N4MSIZ6Rp8vON+hdwtpa0fvH6pYEBLgwsj9M5od4= Date: Fri, 18 Sep 2026 13:05:41 -0700 From: Andrew Morton To: Sebastian Andrzej Siewior Cc: linux-mm@kvack.org, Uladzislau Rezki Subject: Re: [PATCH] mm/vmalloc: Use %p for pointer formatting Message-Id: <20260918130541.8962a797eeb80cab07b18f19@linux-foundation.org> In-Reply-To: <20260918105013.UpdykT6j@linutronix.de> References: <20260918105013.UpdykT6j@linutronix.de> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 9DB7C180004 X-Stat-Signature: gc764is8h5bfs4c61usb6kitgo5drqpx X-HE-Tag: 1789761942-267912 X-HE-Meta: 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 CPJMSDGb iq7JFdKvK+W1WEu1tk0FpgqjB8xVEsR8yozN97TOLhQU6YmkCs3dDA5Oos7xzY+dZAK9jqQEbz9W38b3cUXsmn8shnBMngD1xvzKOkvppncwbfRXwIv7bAGm7GvLkrkEgyVeZtqeEJYbejXOCJfs8RvKBRo0D+FDLqwWNBG/LZ+V9uSZsdPfjcCjqb0UBkKSYOgX/1ca2C9PQZb4+kx+L/fvuk6dWQ2dyExjOadZVCV0xlXQYu7lDs4xKB+lzRlJL3rNpaFiX4uZdJncLq3r1ECnAS9rple0O4VLOBYwuwt+FZ+Q= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, 18 Sep 2026 12:50:13 +0200 Sebastian Andrzej Siewior 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.