On 03/28/2017 10:57 AM, Florian Fainelli wrote:
> Provide hooks to intercept bad usages of virt_to_phys() and
> __pa_symbol() throughout the kernel. To make this possible, we need to
> rename the current implement of virt_to_phys() into
> __virt_to_phys_nodebug() and wrap it around depending on
> CONFIG_DEBUG_VIRTUAL.
>
> A similar thing is needed for __pa_symbol() which is now aliased to
> __phys_addr_symbol() whose implementation is either the direct return of
> RELOC_HIDE or goes through the debug version.
Ping? This may not longer apply cleanly against arch/mips/Kconfig, but
the conflicts should be trivial to resolve.
Thanks.
>
> Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
> ---
> arch/mips/Kconfig | 1 +
> arch/mips/include/asm/io.h | 14 +++++++++++++-
> arch/mips/include/asm/page.h | 9 ++++++++-
> arch/mips/mm/Makefile | 2 ++
> arch/mips/mm/physaddr.c | 40 ++++++++++++++++++++++++++++++++++++++++
> 5 files changed, 64 insertions(+), 2 deletions(-)
> create mode 100644 arch/mips/mm/physaddr.c
>
> diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
> index 2afb41c52ba0..724457b5a7eb 100644
> --- a/arch/mips/Kconfig
> +++ b/arch/mips/Kconfig
> @@ -70,6 +70,7 @@ config MIPS
> select HAVE_EXIT_THREAD
> select HAVE_REGS_AND_STACK_ACCESS_API
> select HAVE_ARCH_HARDENED_USERCOPY
> + select ARCH_HAS_DEBUG_VIRTUAL
>
> menu "Machine selection"
>
> diff --git a/arch/mips/include/asm/io.h b/arch/mips/include/asm/io.h
> index ecabc00c1e66..016e12161c9d 100644
> --- a/arch/mips/include/asm/io.h
> +++ b/arch/mips/include/asm/io.h
> @@ -116,11 +116,23 @@ static inline void set_io_port_base(unsigned long base)
> * almost all conceivable cases a device driver should not be using
> * this function
> */
> -static inline unsigned long virt_to_phys(volatile const void *address)
> +static inline unsigned long __virt_to_phys_nodebug(volatile const void *address)
> {
> return __pa(address);
> }
>
> +#ifdef CONFIG_DEBUG_VIRTUAL
> +extern phys_addr_t __virt_to_phys(volatile const void *x);
> +#else
> +#define __virt_to_phys(x) __virt_to_phys_nodebug(x)
> +#endif
> +
> +#define virt_to_phys virt_to_phys
> +static inline phys_addr_t virt_to_phys(const volatile void *x)
> +{
> + return __virt_to_phys(x);
> +}
> +
> /*
> * phys_to_virt - map physical address to virtual
> * @address: address to remap
> diff --git a/arch/mips/include/asm/page.h b/arch/mips/include/asm/page.h
> index 5f987598054f..bf8bd7d77fce 100644
> --- a/arch/mips/include/asm/page.h
> +++ b/arch/mips/include/asm/page.h
> @@ -205,9 +205,16 @@ static inline unsigned long ___pa(unsigned long x)
> * until GCC 3.x has been retired before we can apply
> * https://patchwork.linux-mips.org/patch/1541/
> */
> +#define __pa_symbol_nodebug(x) __pa(RELOC_HIDE((unsigned long)(x), 0))
> +
> +#ifdef CONFIG_DEBUG_VIRTUAL
> +extern phys_addr_t __phys_addr_symbol(unsigned long x);
> +#else
> +#define __phys_addr_symbol(x) __pa_symbol_nodebug(x)
> +#endif
>
> #ifndef __pa_symbol
> -#define __pa_symbol(x) __pa(RELOC_HIDE((unsigned long)(x), 0))
> +#define __pa_symbol(x) __phys_addr_symbol((unsigned long)(x))
> #endif
>
> #define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT)
> diff --git a/arch/mips/mm/Makefile b/arch/mips/mm/Makefile
> index b4cc8811a664..0a1d241c50fb 100644
> --- a/arch/mips/mm/Makefile
> +++ b/arch/mips/mm/Makefile
> @@ -29,3 +29,5 @@ obj-$(CONFIG_R5000_CPU_SCACHE) += sc-r5k.o
> obj-$(CONFIG_RM7000_CPU_SCACHE) += sc-rm7k.o
> obj-$(CONFIG_MIPS_CPU_SCACHE) += sc-mips.o
> obj-$(CONFIG_SCACHE_DEBUGFS) += sc-debugfs.o
> +
> +obj-$(CONFIG_DEBUG_VIRTUAL) += physaddr.o
> diff --git a/arch/mips/mm/physaddr.c b/arch/mips/mm/physaddr.c
> new file mode 100644
> index 000000000000..6123a9b3b3c0
> --- /dev/null
> +++ b/arch/mips/mm/physaddr.c
> @@ -0,0 +1,40 @@
> +#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/io.h>
> +#include <asm/page.h>
> +#include <asm/dma.h>
> +
> +static inline bool __debug_virt_addr_valid(unsigned long x)
> +{
> + if (x >= PAGE_OFFSET && x < (unsigned long)high_memory)
> + return true;
> +
> + return false;
> +}
> +
> +phys_addr_t __virt_to_phys(volatile const void *x)
> +{
> + WARN(!__debug_virt_addr_valid((unsigned long)x),
> + "virt_to_phys used for non-linear address: %pK (%pS)\n",
> + x, 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)_text ||
> + x > (unsigned long)_end);
> +
> + return __pa_symbol_nodebug(x);
> +}
> +EXPORT_SYMBOL(__phys_addr_symbol);
>
--
Florian
