From 4dd7554a6456d124c85e0a4ad156625b71390b5c Mon Sep 17 00:00:00 2001
From: Nicholas Piggin <npiggin@gmail.com>
Date: Wed, 24 Jul 2019 18:46:37 +1000
Subject: [PATCH] powerpc/64: Add VIRTUAL_BUG_ON checks for __va and __pa
addresses
Ensure __va is given a physical address below PAGE_OFFSET, and __pa is
given a virtual address above PAGE_OFFSET.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190724084638.24982-4-npiggin@gmail.com
---
arch/powerpc/include/asm/page.h | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h
index 0d52f57fca04f..c8bb14ff47135 100644
--- a/arch/powerpc/include/asm/page.h
+++ b/arch/powerpc/include/asm/page.h
@@ -215,9 +215,19 @@ static inline bool pfn_valid(unsigned long pfn)
/*
* gcc miscompiles (unsigned long)(&static_var) - PAGE_OFFSET
* with -mcmodel=medium, so we use & and | instead of - and + on 64-bit.
+ * This also results in better code generation.
*/
-#define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) | PAGE_OFFSET))
-#define __pa(x) ((unsigned long)(x) & 0x0fffffffffffffffUL)
+#define __va(x) \
+({ \
+ VIRTUAL_BUG_ON((unsigned long)(x) >= PAGE_OFFSET); \
+ (void *)(unsigned long)((phys_addr_t)(x) | PAGE_OFFSET); \
+})
+
+#define __pa(x) \
+({ \
+ VIRTUAL_BUG_ON((unsigned long)(x) < PAGE_OFFSET); \
+ (unsigned long)(x) & 0x0fffffffffffffffUL; \
+})
#else /* 32-bit, non book E */
#define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) + PAGE_OFFSET - MEMORY_START))
--
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