mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-15 08:14:15 +08:00
e377cd8221
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: Russell King <rmk+kernel@armlinux.org.uk> Acked-by: Laura Abbott <labbott@redhat.com> Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
58 lines
1.4 KiB
C
58 lines
1.4 KiB
C
#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);
|