[PATCH v2] powerpc/mm: Fix return type of pgd_val()

Christophe Leroy christophe.leroy at csgroup.eu
Thu Aug 22 17:58:42 AEST 2024


Commit 6b0e82791bd0 ("powerpc/e500: switch to 64 bits PGD on 85xx
(32 bits)") switched PGD entries to 64 bits, but pgd_val() returns
an unsigned long which is 32 bits on PPC32. This is not a problem
for regular PMD entries because the upper part is always NULL, but
when PMD entries are leaf they contain 64 bits values, so pgd_val()
must return an unsigned long long instead of an unsigned long.

Also change the condition to CONFIG_PPC_85xx instead of CONFIG_PPC_E500
as the change was meant for 32 bits only. Allthough this should be
harmless on PPC64, it generates a warning with pgd_ERROR print.

Fixes: 6b0e82791bd0 ("powerpc/e500: switch to 64 bits PGD on 85xx (32 bits)")
Signed-off-by: Christophe Leroy <christophe.leroy at csgroup.eu>
---
v2: Limit it to CONFIG_PPC_85xx and use a cast instead of duplicating pgd_ERROR
---
 arch/powerpc/include/asm/nohash/32/pgtable.h |  4 ++--
 arch/powerpc/include/asm/pgtable-types.h     | 12 +++++++++---
 2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/arch/powerpc/include/asm/nohash/32/pgtable.h b/arch/powerpc/include/asm/nohash/32/pgtable.h
index 9508399dd036..b481738c4bb5 100644
--- a/arch/powerpc/include/asm/nohash/32/pgtable.h
+++ b/arch/powerpc/include/asm/nohash/32/pgtable.h
@@ -52,7 +52,7 @@
 #define USER_PTRS_PER_PGD	(TASK_SIZE / PGDIR_SIZE)
 
 #define pgd_ERROR(e) \
-	pr_err("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
+	pr_err("%s:%d: bad pgd %08llx.\n", __FILE__, __LINE__, (unsigned long long)pgd_val(e))
 
 /*
  * This is the bottom of the PKMAP area with HIGHMEM or an arbitrary
@@ -170,7 +170,7 @@ static inline void pmd_clear(pmd_t *pmdp)
 #define pmd_pfn(pmd)		(pmd_val(pmd) >> PAGE_SHIFT)
 #else
 #define pmd_page_vaddr(pmd)	\
-	((const void *)(pmd_val(pmd) & ~(PTE_TABLE_SIZE - 1)))
+	((const void *)((unsigned long)pmd_val(pmd) & ~(PTE_TABLE_SIZE - 1)))
 #define pmd_pfn(pmd)		(__pa(pmd_val(pmd)) >> PAGE_SHIFT)
 #endif
 
diff --git a/arch/powerpc/include/asm/pgtable-types.h b/arch/powerpc/include/asm/pgtable-types.h
index 7b3d4c592a10..f3086e39e7d2 100644
--- a/arch/powerpc/include/asm/pgtable-types.h
+++ b/arch/powerpc/include/asm/pgtable-types.h
@@ -49,16 +49,22 @@ static inline unsigned long pud_val(pud_t x)
 #endif /* CONFIG_PPC64 */
 
 /* PGD level */
-#if defined(CONFIG_PPC_E500) && defined(CONFIG_PTE_64BIT)
+#if defined(CONFIG_PPC_85xx) && defined(CONFIG_PTE_64BIT)
 typedef struct { unsigned long long pgd; } pgd_t;
+
+static inline unsigned long long pgd_val(pgd_t x)
+{
+	return x.pgd;
+}
 #else
 typedef struct { unsigned long pgd; } pgd_t;
-#endif
-#define __pgd(x)	((pgd_t) { (x) })
+
 static inline unsigned long pgd_val(pgd_t x)
 {
 	return x.pgd;
 }
+#endif
+#define __pgd(x)	((pgd_t) { (x) })
 
 /* Page protection bits */
 typedef struct { unsigned long pgprot; } pgprot_t;
-- 
2.44.0



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