[tip: timers/vdso] x86/vdso: Place vdso_data at beginning of vvar page

tip-bot2 for Thomas Weißschuh posted 1 patch 3 weeks, 1 day ago
arch/x86/include/asm/vvar.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
[tip: timers/vdso] x86/vdso: Place vdso_data at beginning of vvar page
Posted by tip-bot2 for Thomas Weißschuh 3 weeks, 1 day ago
The following commit has been merged into the timers/vdso branch of tip:

Commit-ID:     9f8514cfcdf0d929e2d3d440c0d4991f16b7e53b
Gitweb:        https://git.kernel.org/tip/9f8514cfcdf0d929e2d3d440c0d4991f16b7e53b
Author:        Thomas Weißschuh <thomas.weissschuh@linutronix.de>
AuthorDate:    Thu, 10 Oct 2024 09:01:14 +02:00
Committer:     Thomas Gleixner <tglx@linutronix.de>
CommitterDate: Sat, 02 Nov 2024 12:37:34 +01:00

x86/vdso: Place vdso_data at beginning of vvar page

The offset of the vdso_data only has historic reasons, as back then
other vvars also existed and offset 0 was already used.
(See commit 8c49d9a74bac ("x86-64: Clean up vdso/kernel shared variables"))
Over time most other vvars got removed and offset 0 is free again.

Moving vdso_data to the beginning of the vvar page aligns x86 with other
architectures and opens up the way for the removal of the custom x86
vvar machinery.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20241010-vdso-generic-base-v1-12-b64f0842d512@linutronix.de

---
 arch/x86/include/asm/vvar.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/vvar.h b/arch/x86/include/asm/vvar.h
index 9d9af37..01e60e0 100644
--- a/arch/x86/include/asm/vvar.h
+++ b/arch/x86/include/asm/vvar.h
@@ -58,7 +58,7 @@ extern char __vvar_page;
 
 /* DECLARE_VVAR(offset, type, name) */
 
-DECLARE_VVAR(128, struct vdso_data, _vdso_data)
+DECLARE_VVAR(0, struct vdso_data, _vdso_data)
 
 #if !defined(_SINGLE_DATA)
 #define _SINGLE_DATA