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mips: define pud_index() regardless of page table folding

PATCH Applied Mike Rapoport 4 participants 4 messages Apr 2, 2020 – Apr 16, 2020

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Mike Rapoport

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#0 lore raw

PATCH 1/1 mips: define pud_index() regardless of page table folding

From: Mike Rapoport <[email protected]>

Commit 31168f033e37 ("mips: drop __pXd_offset() macros that duplicate pXd_index() ones") is correct that pud_index() & __pud_offset() are the same when pud_index() is actually provided, however it does not take into account the __PAGETABLE_PUD_FOLDED case. This has broken MIPS KVM compilation because it relied on availability of pud_index().

Define pud_index() regardless of page table folded. It will evaluate to actual index for 4-level pagetables and to 0 for folded PUD level.

Link https://lore.kernel.org/lkml/[email protected] open here
Reported-by Paolo Bonzini <[email protected]>
Signed-off-by Mike Rapoport <[email protected]>
---
 arch/mips/include/asm/pgtable-64.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
arch/mips/include/asm/pgtable-64.h +2 -2
index f92716cfa4f4..ee5dc0c145b9 100644
@@ -172,6 +172,8 @@
 
 extern pte_t invalid_pte_table[PTRS_PER_PTE];
 
+#define pud_index(address)	(((address) >> PUD_SHIFT) & (PTRS_PER_PUD - 1))
+
 #ifndef __PAGETABLE_PUD_FOLDED
 /*
  * For 4-level pagetables we defines these ourselves, for 3-level the

@@ -210,8 +212,6 @@ static inline void p4d_clear(p4d_t *p4dp)
 	p4d_val(*p4dp) = (unsigned long)invalid_pud_table;
 }
 
-#define pud_index(address)	(((address) >> PUD_SHIFT) & (PTRS_PER_PUD - 1))
-
 static inline unsigned long p4d_page_vaddr(p4d_t p4d)
 {
 	return p4d_val(p4d);
Signature · 1 line
2.25.1
Tested-by on v1 1/1
#1 lore raw
Tested-by Huacai Chen <[email protected]>
Quoted 44 lines · Mike Rapoport

From: Mike Rapoport <[email protected]>

Commit 31168f033e37 ("mips: drop __pXd_offset() macros that duplicate pXd_index() ones") is correct that pud_index() & __pud_offset() are the same when pud_index() is actually provided, however it does not take into account the __PAGETABLE_PUD_FOLDED case. This has broken MIPS KVM compilation because it relied on availability of pud_index().

Define pud_index() regardless of page table folded. It will evaluate to actual index for 4-level pagetables and to 0 for folded PUD level.

Link https://lore.kernel.org/lkml/[email protected] open here
Reported-by Paolo Bonzini <[email protected]>
Signed-off-by Mike Rapoport <[email protected]>
---
 arch/mips/include/asm/pgtable-64.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
arch/mips/include/asm/pgtable-64.h +2 -3
index f92716cfa4f4..ee5dc0c145b9 100644
@@ -172,6 +172,8 @@
 
 extern pte_t invalid_pte_table[PTRS_PER_PTE];
 
+#define pud_index(address)     (((address) >> PUD_SHIFT) & (PTRS_PER_PUD - 1))
+
 #ifndef __PAGETABLE_PUD_FOLDED
 /*
  * For 4-level pagetables we defines these ourselves, for 3-level the

@@ -210,8 +212,6 @@ static inline void p4d_clear(p4d_t *p4dp)
        p4d_val(*p4dp) = (unsigned long)invalid_pud_table;
 }
 
-#define pud_index(address)     (((address) >> PUD_SHIFT) & (PTRS_PER_PUD - 1))
-
 static inline unsigned long p4d_page_vaddr(p4d_t p4d)
 {
        return p4d_val(p4d);
--

2.25.1

Reviewed-by on v1 1/1
#2 lore raw
In reply to Mike Rapoport
Quoted 8 lines · Mike Rapoport

From: Mike Rapoport <[email protected]>

Commit 31168f033e37 ("mips: drop __pXd_offset() macros that duplicate pXd_index() ones") is correct that pud_index() & __pud_offset() are the same when pud_index() is actually provided, however it does not take into account the __PAGETABLE_PUD_FOLDED case. This has broken MIPS KVM compilation because it relied on availability of pud_index().

Quoted 6 lines

Define pud_index() regardless of page table folded. It will evaluate to actual index for 4-level pagetables and to 0 for folded PUD level.

Link https://lore.kernel.org/lkml/[email protected] open here
Reported-by Paolo Bonzini <[email protected]>
Signed-off-by Mike Rapoport <[email protected]>
Reviewed-by Philippe Mathieu-Daudé <[email protected]>
Quoted 27 lines
---
 arch/mips/include/asm/pgtable-64.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
arch/mips/include/asm/pgtable-64.h +2 -2
index f92716cfa4f4..ee5dc0c145b9 100644
@@ -172,6 +172,8 @@
 
 extern pte_t invalid_pte_table[PTRS_PER_PTE];
 
+#define pud_index(address)	(((address) >> PUD_SHIFT) & (PTRS_PER_PUD - 1))
+
 #ifndef __PAGETABLE_PUD_FOLDED
 /*
  * For 4-level pagetables we defines these ourselves, for 3-level the

@@ -210,8 +212,6 @@ static inline void p4d_clear(p4d_t *p4dp)
 	p4d_val(*p4dp) = (unsigned long)invalid_pud_table;
 }
 
-#define pud_index(address)	(((address) >> PUD_SHIFT) & (PTRS_PER_PUD - 1))
-
 static inline unsigned long p4d_page_vaddr(p4d_t p4d)
 {
 	return p4d_val(p4d);
maintainer Applied
#3 lore raw
In reply to Mike Rapoport
Quoted 11 lines · Mike Rapoport

From: Mike Rapoport <[email protected]>

Commit 31168f033e37 ("mips: drop __pXd_offset() macros that duplicate pXd_index() ones") is correct that pud_index() & __pud_offset() are the same when pud_index() is actually provided, however it does not take into account the __PAGETABLE_PUD_FOLDED case. This has broken MIPS KVM compilation because it relied on availability of pud_index().

Define pud_index() regardless of page table folded. It will evaluate to actual index for 4-level pagetables and to 0 for folded PUD level.

Quoted 6 lines
Link https://lore.kernel.org/lkml/[email protected] open here
Reported-by Paolo Bonzini <[email protected]>
Signed-off-by Mike Rapoport <[email protected]>
---
 arch/mips/include/asm/pgtable-64.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

applied to mips-next.

Thomas.

Signature · 2 lines
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good idea.                                                [ RFC1925, 2.3 ]