From eea1bb2248691ed65c33daff94a253af44feb103 Mon Sep 17 00:00:00 2001 From: Miles Chen Date: Tue, 16 Apr 2019 01:36:36 +0800 Subject: [PATCH] arm64: mm: check virtual addr in virt_to_page() if CONFIG_DEBUG_VIRTUAL=y This change uses the original virt_to_page() (the one with __pa()) to check the given virtual address if CONFIG_DEBUG_VIRTUAL=y. Recently, I worked on a bug: a driver passes a symbol address to dma_map_single() and the virt_to_page() (called by dma_map_single()) does not work for non-linear addresses after commit 9f2875912dac ("arm64: mm: restrict virt_to_page() to the linear mapping"). I tried to trap the bug by enabling CONFIG_DEBUG_VIRTUAL but it did not work - bacause the commit removes the __pa() from virt_to_page() but CONFIG_DEBUG_VIRTUAL checks the virtual address in __pa()/__virt_to_phys(). A simple solution is to use the original virt_to_page() (the one with__pa()) if CONFIG_DEBUG_VIRTUAL=y. Cc: Ard Biesheuvel Acked-by: Catalin Marinas Signed-off-by: Miles Chen Signed-off-by: Will Deacon --- arch/arm64/include/asm/memory.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h index 2901951..2cb8248 100644 --- a/arch/arm64/include/asm/memory.h +++ b/arch/arm64/include/asm/memory.h @@ -302,7 +302,7 @@ static inline void *phys_to_virt(phys_addr_t x) */ #define ARCH_PFN_OFFSET ((unsigned long)PHYS_PFN_OFFSET) -#ifndef CONFIG_SPARSEMEM_VMEMMAP +#if !defined(CONFIG_SPARSEMEM_VMEMMAP) || defined(CONFIG_DEBUG_VIRTUAL) #define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT) #define _virt_addr_valid(kaddr) pfn_valid(__pa(kaddr) >> PAGE_SHIFT) #else -- 2.7.4