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From: Yeoreum Yun <yeoreum.yun@arm.com>
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	Yeoreum Yun <yeoreum.yun@arm.com>
Subject: [RFC PATCH 01/34] ARM: mm: make nommu pgd_t a scalar
Date: Mon, 13 Jul 2026 14:55:40 +0100	[thread overview]
Message-ID: <20260713135614.1618183-2-yeoreum.yun@arm.com> (raw)
In-Reply-To: <20260713135614.1618183-1-yeoreum.yun@arm.com>

From: "David Hildenbrand (Arm)" <david@kernel.org>

We don't want pgd_t to be an array, as it prohibits returning it from a
function, like ptep_get().

There is no need to match the actual arm page tables, because with nommu
there are no page tables. It's all just in place to make the compiler
happy. Making it a scalar will make the compiler happy.

So let's just use an u32.

Signed-off-by: David Hildenbrand (Arm) <david@kernel.org>
Signed-off-by: Yeoreum Yun <yeoreum.yun@arm.com>
---
 arch/arm/include/asm/page-nommu.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm/include/asm/page-nommu.h b/arch/arm/include/asm/page-nommu.h
index e74415c959bea..88659b38e2364 100644
--- a/arch/arm/include/asm/page-nommu.h
+++ b/arch/arm/include/asm/page-nommu.h
@@ -18,12 +18,12 @@
  */
 typedef unsigned long pte_t;
 typedef unsigned long pmd_t;
-typedef unsigned long pgd_t[2];
+typedef unsigned long pgd_t;
 typedef unsigned long pgprot_t;
 
 #define pte_val(x)      (x)
 #define pmd_val(x)      (x)
-#define pgd_val(x)	((x)[0])
+#define pgd_val(x)      (x)
 #define pgprot_val(x)   (x)
 
 #define __pte(x)        (x)
-- 
LEVI:{C3F47F37-75D8-414A-A8BA-3980EC8A46D7}


  reply	other threads:[~2026-07-13 13:56 UTC|newest]

Thread overview: 86+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-07-13 13:55 [RFC PATCH 00/34] mm: optimize unnecessary loads due to ptep_get() and friends out Yeoreum Yun
2026-07-13 13:55 ` Yeoreum Yun [this message]
2026-07-13 13:55 ` [RFC PATCH 02/34] ARM: mm: make 2-level pgd_t a scalar Yeoreum Yun
2026-07-13 15:38   ` Arnd Bergmann
2026-07-13 16:04     ` David Hildenbrand (Arm)
2026-07-13 16:26       ` David Hildenbrand (Arm)
2026-07-14 10:26   ` Pedro Falcato
2026-07-14 10:54     ` David Hildenbrand (Arm)
2026-07-14 11:55     ` Arnd Bergmann
2026-07-14 13:34       ` David Laight
2026-07-14 15:06         ` Arnd Bergmann
2026-07-14 21:45           ` David Laight
2026-07-15  6:11             ` Arnd Bergmann
2026-07-16 19:04       ` Yeoreum Yun
2026-07-17  6:16         ` Arnd Bergmann
2026-07-17  7:55           ` Yeoreum Yun
2026-07-14 12:34   ` David Laight
2026-07-14 13:03     ` David Hildenbrand (Arm)
2026-07-15  6:15   ` Arnd Bergmann
2026-07-15  9:41     ` David Hildenbrand (Arm)
2026-07-16 10:56     ` Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 03/34] ARM: mm: remove custom pgdp_get() Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 04/34] LoongArch: mm: define pud_leaf() only when PUD exists Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 05/34] MIPS: " Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 06/34] mm/pgtable: define (pgd|p4d|pud)_leaf() for folded page tables Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 07/34] mm/pgtable: define (pgd|p4d|pud)_offset_lockless() " Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 08/34] loongarch: kvm: remove stack copy address of pXd in pXd_offset() Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 09/34] riscv: " Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 10/34] x86: mm: carve out the generic compile-time folded pgtable case in effective_prot() Yeoreum Yun
2026-07-13 14:19   ` Dave Hansen
2026-07-13 14:41     ` David Hildenbrand (Arm)
2026-07-13 14:55       ` Dave Hansen
2026-07-13 15:02         ` David Hildenbrand (Arm)
2026-07-13 17:57           ` Dave Hansen
2026-07-13 19:49             ` David Hildenbrand (Arm)
2026-07-13 20:27               ` Dave Hansen
2026-07-13 21:17                 ` David Hildenbrand (Arm)
2026-07-13 21:40                   ` Dave Hansen
2026-07-14 10:50                     ` David Hildenbrand (Arm)
2026-07-14 11:40                       ` Yeoreum Yun
2026-07-14 14:35                         ` Dave Hansen
2026-07-14 16:08                           ` Yeoreum Yun
2026-07-14 16:31                             ` David Hildenbrand (Arm)
2026-07-14 18:28                               ` Yeoreum Yun
2026-07-15  9:43                                 ` David Hildenbrand (Arm)
2026-07-14 16:51                             ` Yeoreum Yun
2026-07-14 17:29                               ` David Hildenbrand (Arm)
2026-07-14 17:58                                 ` Yeoreum Yun
2026-07-15  9:44                                   ` David Hildenbrand (Arm)
2026-07-16  8:47                                     ` Yeoreum Yun
2026-07-15  7:45                               ` Geert Uytterhoeven
2026-07-15  9:41                                 ` Yeoreum Yun
2026-07-15 10:34                                   ` Geert Uytterhoeven
2026-07-16  7:49                                     ` Yeoreum Yun
2026-07-21 17:45                         ` Yeoreum Yun
2026-07-21 18:21                           ` David Hildenbrand (Arm)
2026-07-13 14:48     ` Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 11/34] mm: vmscan: remove stack copy address of pud pass in wallk_pud_range() Yeoreum Yun
2026-07-15 13:44   ` Usama Anjum
2026-07-13 13:55 ` [RFC PATCH 12/34] arm64: mm: use proper set_pXd() for generic compile-time folded patable in kasan_early_init() Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 13/34] arm64: mm: define pud_set_huge() when __PGTABLE_PMD_FOLDED not defined Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 14/34] csky: mm: use proper set_pXd() for generic compile-time folded patable in vmalloc_fault() Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 15/34] mips: mm: use proper set_pXd() for generic compile-time folded patable in vmalloc_fault path Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 16/34] nios2: " Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 17/34] riscv: mm: use proper set_pXd() for generic compile-time folded patable in vmalloc_fault() Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 18/34] riscv: mm: use proper set_pXd() for generic compile-time folded patable in setup_vm_final() Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 19/34] x86: power: use proper set_pXd() for generic compile-time folded patable in resume_one_md_table_init() Yeoreum Yun
2026-07-13 14:38   ` Dave Hansen
2026-07-13 14:59     ` David Hildenbrand (Arm)
2026-07-13 15:01     ` Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 20/34] x86: kexec: use proper set_pXd() for generic compile-time folded patable in machine_kexec_page_table_set_one() Yeoreum Yun
2026-07-13 13:56 ` [RFC PATCH 21/34] x86: platform: use proper set_pXd() for generic compile-time folded patable in setup_olpc_ofw_pgd() Yeoreum Yun
2026-07-13 13:56 ` [RFC PATCH 22/34] x86: mm: use proper set_pXd() for generic compile-time folded patable in one_md_table_init() Yeoreum Yun
2026-07-13 13:56 ` [RFC PATCH 23/34] x86: mm: skip pud setup when using generic compile-time folded pagetable Yeoreum Yun
2026-07-13 13:56 ` [RFC PATCH 24/34] x86: mm: call try_to_free_pmd_page() when CONFIG_PGTABLE_LEVELS > 2 Yeoreum Yun
2026-07-13 13:56 ` [RFC PATCH 25/34] x86: mm: remove usage of pgd_page_vaddr() for CONFIG_x86_PAE Yeoreum Yun
2026-07-13 13:56 ` [RFC PATCH 26/34] x86: mm: define pudp_set_access_flags() when CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD is enabled only Yeoreum Yun
2026-07-13 13:56 ` [RFC PATCH 27/34] m68k: mm: remove usage of pgd_page_vaddr() for CONFIG_PGTABLE_LEVELS=3 Yeoreum Yun
2026-07-13 13:56 ` [RFC PATCH 28/34] arm: mm: use proper pgtable APIs for generic compile-time folded patable in kasan_init() Yeoreum Yun
2026-07-13 13:56 ` [RFC PATCH 29/34] mm/pgtable: disallow calling folded set_pgd/set_p4d/set_pud Yeoreum Yun
2026-07-13 13:56 ` [RFC PATCH 30/34] mm/pgtable: disallow calling folded (pgd|p4d|pud)_page, pgd_page_vaddr() and (p4d|pud)_pgtable Yeoreum Yun
2026-07-13 13:56 ` [RFC PATCH 31/34] mm/pgtable: optimize pmdp_get() and friends for folded pagetable levels Yeoreum Yun
2026-07-13 13:56 ` [RFC PATCH 32/34] openrisc/pgtable: drop __pmd_offset() Yeoreum Yun
2026-07-13 13:56 ` [RFC PATCH 33/34] mm/pgtable: catch abuse of folded dummy pgd_t/p4d_t/pud_t Yeoreum Yun
2026-07-13 13:56 ` [RFC PATCH 34/34] arm64: pgtable: convert pte_present() from macro to static inline Yeoreum Yun
2026-07-13 14:08 ` [RFC PATCH 00/34] mm: optimize unnecessary loads due to ptep_get() and friends out David Hildenbrand (Arm)

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