The following commit has been merged into the timers/vdso branch of tip:
Commit-ID: c3a190d425916e84bbda65873f9fc27ce4b82893
Gitweb: https://git.kernel.org/tip/c3a190d425916e84bbda65873f9fc27ce4b82893
Author: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
AuthorDate: Thu, 10 Oct 2024 09:01:18 +02:00
Committer: Thomas Gleixner <tglx@linutronix.de>
CommitterDate: Sat, 02 Nov 2024 12:37:34 +01:00
x86/vdso: Access rng vdso data without vvar.h
The vdso_rng_data is at a well-known offset in the vvar page.
Make use of this invariant to remove the usage of vvar.h.
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-v1-16-b64f0842d512@linutronix.de
---
arch/x86/entry/vdso/vdso-layout.lds.S | 2 ++
arch/x86/include/asm/vdso/getrandom.h | 8 ++++----
arch/x86/include/asm/vvar.h | 5 -----
3 files changed, 6 insertions(+), 9 deletions(-)
diff --git a/arch/x86/entry/vdso/vdso-layout.lds.S b/arch/x86/entry/vdso/vdso-layout.lds.S
index 51c0cc0..acce607 100644
--- a/arch/x86/entry/vdso/vdso-layout.lds.S
+++ b/arch/x86/entry/vdso/vdso-layout.lds.S
@@ -24,6 +24,8 @@ SECTIONS
#include <asm/vvar.h>
#undef EMIT_VVAR
+ vdso_rng_data = vvar_page + __VDSO_RND_DATA_OFFSET;
+
pvclock_page = vvar_start + PAGE_SIZE;
hvclock_page = vvar_start + 2 * PAGE_SIZE;
timens_page = vvar_start + 3 * PAGE_SIZE;
diff --git a/arch/x86/include/asm/vdso/getrandom.h b/arch/x86/include/asm/vdso/getrandom.h
index d0713c8..2bf9c0e 100644
--- a/arch/x86/include/asm/vdso/getrandom.h
+++ b/arch/x86/include/asm/vdso/getrandom.h
@@ -8,7 +8,6 @@
#ifndef __ASSEMBLY__
#include <asm/unistd.h>
-#include <asm/vvar.h>
/**
* getrandom_syscall - Invoke the getrandom() syscall.
@@ -28,13 +27,14 @@ static __always_inline ssize_t getrandom_syscall(void *buffer, size_t len, unsig
return ret;
}
-#define __vdso_rng_data (VVAR(_vdso_rng_data))
+extern struct vdso_rng_data vdso_rng_data
+ __attribute__((visibility("hidden")));
static __always_inline const struct vdso_rng_data *__arch_get_vdso_rng_data(void)
{
if (IS_ENABLED(CONFIG_TIME_NS) && __arch_get_vdso_data()->clock_mode == VDSO_CLOCKMODE_TIMENS)
- return (void *)&__vdso_rng_data + ((void *)&timens_page - (void *)__arch_get_vdso_data());
- return &__vdso_rng_data;
+ return (void *)&vdso_rng_data + ((void *)&timens_page - (void *)__arch_get_vdso_data());
+ return &vdso_rng_data;
}
#endif /* !__ASSEMBLY__ */
diff --git a/arch/x86/include/asm/vvar.h b/arch/x86/include/asm/vvar.h
index fe3434d..b605914 100644
--- a/arch/x86/include/asm/vvar.h
+++ b/arch/x86/include/asm/vvar.h
@@ -62,11 +62,6 @@ extern char __vvar_page;
DECLARE_VVAR(0, struct vdso_data, _vdso_data)
-#if !defined(_SINGLE_DATA)
-#define _SINGLE_DATA
-DECLARE_VVAR_SINGLE(__VDSO_RND_DATA_OFFSET, struct vdso_rng_data, _vdso_rng_data)
-#endif
-
#undef DECLARE_VVAR
#undef DECLARE_VVAR_SINGLE