[PATCH 5/6] powerpc/64: Only WARN if __pa()/__va() called with bad addresses

Michael Ellerman mpe at ellerman.id.au
Thu Apr 7 00:58:01 AEST 2022


We added checks to __pa() / __va() to ensure they're only called with
appropriate addresses. But using BUG_ON() is too strong, it means
virt_addr_valid() will BUG when DEBUG_VIRTUAL is enabled.

Instead switch them to warnings, arm64 does the same.

Fixes: 4dd7554a6456 ("powerpc/64: Add VIRTUAL_BUG_ON checks for __va and __pa addresses")
Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>
---
 arch/powerpc/include/asm/page.h | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h
index f2c5c26869f1..40a27a56ee40 100644
--- a/arch/powerpc/include/asm/page.h
+++ b/arch/powerpc/include/asm/page.h
@@ -216,6 +216,12 @@ static inline bool pfn_valid(unsigned long pfn)
 #define __pa(x) ((phys_addr_t)(unsigned long)(x) - VIRT_PHYS_OFFSET)
 #else
 #ifdef CONFIG_PPC64
+
+#ifdef CONFIG_DEBUG_VIRTUAL
+#define VIRTUAL_WARN_ON(x)	WARN_ON(x)
+#else
+#define VIRTUAL_WARN_ON(x)
+#endif
 /*
  * gcc miscompiles (unsigned long)(&static_var) - PAGE_OFFSET
  * with -mcmodel=medium, so we use & and | instead of - and + on 64-bit.
@@ -223,13 +229,13 @@ static inline bool pfn_valid(unsigned long pfn)
  */
 #define __va(x)								\
 ({									\
-	VIRTUAL_BUG_ON((unsigned long)(x) >= PAGE_OFFSET);		\
+	VIRTUAL_WARN_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);		\
+	VIRTUAL_WARN_ON((unsigned long)(x) < PAGE_OFFSET);		\
 	(unsigned long)(x) & 0x0fffffffffffffffUL;			\
 })
 
-- 
2.34.1



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