[tip: x86/merge] x86/paravirt: Restrict PARAVIRT_XXL to 64-bit only

From: tip-bot2 for Kirill A. Shutemov
Date: Sat May 17 2025 - 09:00:49 EST


The following commit has been merged into the x86/merge branch of tip:

Commit-ID: 09230b7554824c9db1712324efcf3595c67fd326
Gitweb: https://git.kernel.org/tip/09230b7554824c9db1712324efcf3595c67fd326
Author: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
AuthorDate: Fri, 16 May 2025 15:33:06 +03:00
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitterDate: Sat, 17 May 2025 10:38:29 +02:00

x86/paravirt: Restrict PARAVIRT_XXL to 64-bit only

PARAVIRT_XXL is exclusively utilized by XEN_PV, which is only compatible
with 64-bit machines.

Clearly designate PARAVIRT_XXL as 64-bit only and remove ifdefs to
support CONFIG_PGTABLE_LEVELS < 5.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Reviewed-by: Juergen Gross <jgross@xxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20250516123306.3812286-5-kirill.shutemov@xxxxxxxxxxxxxxx
---
arch/x86/Kconfig | 1 +
arch/x86/include/asm/paravirt.h | 4 ----
arch/x86/include/asm/paravirt_types.h | 2 --
arch/x86/kernel/paravirt.c | 2 --
4 files changed, 1 insertion(+), 8 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index bae3e97..121f9f0 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -799,6 +799,7 @@ config PARAVIRT

config PARAVIRT_XXL
bool
+ depends on X86_64

config PARAVIRT_DEBUG
bool "paravirt-ops debugging"
diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index 03f680d..b5e59a7 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -463,8 +463,6 @@ static inline void set_p4d(p4d_t *p4dp, p4d_t p4d)
PVOP_VCALL2(mmu.set_p4d, p4dp, val);
}

-#if CONFIG_PGTABLE_LEVELS >= 5
-
static inline p4d_t __p4d(p4dval_t val)
{
p4dval_t ret = PVOP_ALT_CALLEE1(p4dval_t, mmu.make_p4d, val,
@@ -496,8 +494,6 @@ static inline void __set_pgd(pgd_t *pgdp, pgd_t pgd)
set_pgd(pgdp, native_make_pgd(0)); \
} while (0)

-#endif /* CONFIG_PGTABLE_LEVELS == 5 */
-
static inline void p4d_clear(p4d_t *p4dp)
{
set_p4d(p4dp, native_make_p4d(0));
diff --git a/arch/x86/include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h
index b08b9d3..37a8627 100644
--- a/arch/x86/include/asm/paravirt_types.h
+++ b/arch/x86/include/asm/paravirt_types.h
@@ -189,12 +189,10 @@ struct pv_mmu_ops {

void (*set_p4d)(p4d_t *p4dp, p4d_t p4dval);

-#if CONFIG_PGTABLE_LEVELS >= 5
struct paravirt_callee_save p4d_val;
struct paravirt_callee_save make_p4d;

void (*set_pgd)(pgd_t *pgdp, pgd_t pgdval);
-#endif /* CONFIG_PGTABLE_LEVELS >= 5 */

struct pv_lazy_ops lazy_mode;

diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c
index 015bf29..ab3e172 100644
--- a/arch/x86/kernel/paravirt.c
+++ b/arch/x86/kernel/paravirt.c
@@ -211,12 +211,10 @@ struct paravirt_patch_template pv_ops = {

.mmu.set_p4d = native_set_p4d,

-#if CONFIG_PGTABLE_LEVELS >= 5
.mmu.p4d_val = PTE_IDENT,
.mmu.make_p4d = PTE_IDENT,

.mmu.set_pgd = native_set_pgd,
-#endif /* CONFIG_PGTABLE_LEVELS >= 5 */

.mmu.pte_val = PTE_IDENT,
.mmu.pgd_val = PTE_IDENT,