[tip: timers/core] vdso: Add CONFIG_GENERIC_VDSO_OVERFLOW_PROTECT

From: tip-bot2 for Adrian Hunter
Date: Mon Apr 08 2024 - 09:14:04 EST


The following commit has been merged into the timers/core branch of tip:

Commit-ID: 0c68458b0a5878d735572b4f4d91219a1db7c784
Gitweb: https://git.kernel.org/tip/0c68458b0a5878d735572b4f4d91219a1db7c784
Author: Adrian Hunter <adrian.hunter@xxxxxxxxx>
AuthorDate: Mon, 25 Mar 2024 08:40:07 +02:00
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitterDate: Mon, 08 Apr 2024 15:03:06 +02:00

vdso: Add CONFIG_GENERIC_VDSO_OVERFLOW_PROTECT

Add CONFIG_GENERIC_VDSO_OVERFLOW_PROTECT in preparation to add
multiplication overflow protection to the VDSO time getter functions.

Suggested-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20240325064023.2997-4-adrian.hunter@xxxxxxxxx

---
lib/vdso/Kconfig | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/lib/vdso/Kconfig b/lib/vdso/Kconfig
index d883ac2..c46c230 100644
--- a/lib/vdso/Kconfig
+++ b/lib/vdso/Kconfig
@@ -30,4 +30,11 @@ config GENERIC_VDSO_TIME_NS
Selected by architectures which support time namespaces in the
VDSO

+config GENERIC_VDSO_OVERFLOW_PROTECT
+ bool
+ help
+ Select to add multiplication overflow protection to the VDSO
+ time getter functions for the price of an extra conditional
+ in the hotpath.
+
endif