Commit e377cd82 authored by Florian Fainelli's avatar Florian Fainelli Committed by Russell King
Browse files

ARM: 8640/1: Add support for CONFIG_DEBUG_VIRTUAL



x86 has an option: CONFIG_DEBUG_VIRTUAL to do additional checks on
virt_to_phys calls. The goal is to catch users who are calling
virt_to_phys on non-linear addresses immediately. This includes caller
using __virt_to_phys() on image addresses instead of __pa_symbol(). This
is a generally useful debug feature to spot bad code (particulary in
drivers).

Acked-by: default avatarRussell King <rmk+kernel@armlinux.org.uk>
Acked-by: default avatarLaura Abbott <labbott@redhat.com>
Signed-off-by: default avatarFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent 399f157a
......@@ -2,6 +2,7 @@ config ARM
bool
default y
select ARCH_CLOCKSOURCE_DATA
select ARCH_HAS_DEBUG_VIRTUAL
select ARCH_HAS_DEVMEM_IS_ALLOWED
select ARCH_HAS_ELF_RANDOMIZE
select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
......
......@@ -213,7 +213,7 @@ extern const void *__pv_table_begin, *__pv_table_end;
: "r" (x), "I" (__PV_BITS_31_24) \
: "cc")
static inline phys_addr_t __virt_to_phys(unsigned long x)
static inline phys_addr_t __virt_to_phys_nodebug(unsigned long x)
{
phys_addr_t t;
......@@ -245,7 +245,7 @@ static inline unsigned long __phys_to_virt(phys_addr_t x)
#define PHYS_OFFSET PLAT_PHYS_OFFSET
#define PHYS_PFN_OFFSET ((unsigned long)(PHYS_OFFSET >> PAGE_SHIFT))
static inline phys_addr_t __virt_to_phys(unsigned long x)
static inline phys_addr_t __virt_to_phys_nodebug(unsigned long x)
{
return (phys_addr_t)x - PAGE_OFFSET + PHYS_OFFSET;
}
......@@ -261,6 +261,16 @@ static inline unsigned long __phys_to_virt(phys_addr_t x)
((((unsigned long)(kaddr) - PAGE_OFFSET) >> PAGE_SHIFT) + \
PHYS_PFN_OFFSET)
#define __pa_symbol_nodebug(x) __virt_to_phys_nodebug((x))
#ifdef CONFIG_DEBUG_VIRTUAL
extern phys_addr_t __virt_to_phys(unsigned long x);
extern phys_addr_t __phys_addr_symbol(unsigned long x);
#else
#define __virt_to_phys(x) __virt_to_phys_nodebug(x)
#define __phys_addr_symbol(x) __pa_symbol_nodebug(x)
#endif
/*
* These are *only* valid on the kernel direct mapped RAM memory.
* Note: Drivers should NOT use these. They are the wrong
......@@ -283,6 +293,7 @@ static inline void *phys_to_virt(phys_addr_t x)
* Drivers should NOT use these either.
*/
#define __pa(x) __virt_to_phys((unsigned long)(x))
#define __pa_symbol(x) __phys_addr_symbol(RELOC_HIDE((unsigned long)(x), 0))
#define __va(x) ((void *)__phys_to_virt((phys_addr_t)(x)))
#define pfn_to_kaddr(pfn) __va((phys_addr_t)(pfn) << PAGE_SHIFT)
......
......@@ -14,6 +14,7 @@ endif
obj-$(CONFIG_ARM_PTDUMP) += dump.o
obj-$(CONFIG_MODULES) += proc-syms.o
obj-$(CONFIG_DEBUG_VIRTUAL) += physaddr.o
obj-$(CONFIG_ALIGNMENT_TRAP) += alignment.o
obj-$(CONFIG_HIGHMEM) += highmem.o
......
#include <linux/bug.h>
#include <linux/export.h>
#include <linux/types.h>
#include <linux/mmdebug.h>
#include <linux/mm.h>
#include <asm/sections.h>
#include <asm/memory.h>
#include <asm/fixmap.h>
#include <asm/dma.h>
#include "mm.h"
static inline bool __virt_addr_valid(unsigned long x)
{
/*
* high_memory does not get immediately defined, and there
* are early callers of __pa() against PAGE_OFFSET
*/
if (!high_memory && x >= PAGE_OFFSET)
return true;
if (high_memory && x >= PAGE_OFFSET && x < (unsigned long)high_memory)
return true;
/*
* MAX_DMA_ADDRESS is a virtual address that may not correspond to an
* actual physical address. Enough code relies on __pa(MAX_DMA_ADDRESS)
* that we just need to work around it and always return true.
*/
if (x == MAX_DMA_ADDRESS)
return true;
return false;
}
phys_addr_t __virt_to_phys(unsigned long x)
{
WARN(!__virt_addr_valid(x),
"virt_to_phys used for non-linear address: %pK (%pS)\n",
(void *)x, (void *)x);
return __virt_to_phys_nodebug(x);
}
EXPORT_SYMBOL(__virt_to_phys);
phys_addr_t __phys_addr_symbol(unsigned long x)
{
/* This is bounds checking against the kernel image only.
* __pa_symbol should only be used on kernel symbol addresses.
*/
VIRTUAL_BUG_ON(x < (unsigned long)KERNEL_START ||
x > (unsigned long)KERNEL_END);
return __pa_symbol_nodebug(x);
}
EXPORT_SYMBOL(__phys_addr_symbol);
Supports Markdown
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment