linux-kernel - [PATCH 2/5] vdso: Add comment about reason for vdso struct ordering

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20240701-vdso-cleanup-v1-2-36eb64e7ece2@linutronix.de>
Date: Mon, 01 Jul 2024 16:47:55 +0200
From: Anna-Maria Behnsen <anna-maria@...utronix.de>
To: Andy Lutomirski <luto@...nel.org>, Thomas Gleixner <tglx@...utronix.de>, 
 Vincenzo Frascino <vincenzo.frascino@....com>
Cc: linux-kernel@...r.kernel.org, 
 Anna-Maria Behnsen <anna-maria@...utronix.de>
Subject: [PATCH 2/5] vdso: Add comment about reason for vdso struct
 ordering

Signed-off-by: Anna-Maria Behnsen <anna-maria@...utronix.de>
---
 include/vdso/datapage.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/include/vdso/datapage.h b/include/vdso/datapage.h
index d04d394db064..7647e0946f50 100644
--- a/include/vdso/datapage.h
+++ b/include/vdso/datapage.h
@@ -77,6 +77,10 @@ struct vdso_timestamp {
  * vdso_data will be accessed by 64 bit and compat code at the same time
  * so we should be careful before modifying this structure.
  *
+ * The ordering of the struct members is optimized to have fast access to the
+ * often required struct members which are related to CLOCK_REALTIME and
+ * CLOCK_MONOTONIC. This information is stored in the first cache lines.
+ *
  * @basetime is used to store the base time for the system wide time getter
  * VVAR page.
  *

-- 
2.39.2