| Message ID | 20220929021226.318152-1-chenhuacai@loongson.cn (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | LoongArch: Support access filter to /dev/mem interface | expand |
Hi Huacai,
I love your patch! Perhaps something to improve:
[auto build test WARNING on soc/for-next]
[also build test WARNING on linus/master v6.0-rc7 next-20220928]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Huacai-Chen/LoongArch-Support-access-filter-to-dev-mem-interface/20220929-101532
base: https://git.kernel.org/pub/scm/linux/kernel/git/soc/soc.git for-next
config: loongarch-allyesconfig
compiler: loongarch64-linux-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/ebb5f48a499f12b42fe885735d3678914667fb73
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Huacai-Chen/LoongArch-Support-access-filter-to-dev-mem-interface/20220929-101532
git checkout ebb5f48a499f12b42fe885735d3678914667fb73
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=loongarch SHELL=/bin/bash arch/loongarch/
If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
All warnings (new ones prefixed by >>):
>> arch/loongarch/mm/mmap.c:125:5: warning: no previous prototype for 'valid_phys_addr_range' [-Wmissing-prototypes]
125 | int valid_phys_addr_range(phys_addr_t addr, size_t size)
| ^~~~~~~~~~~~~~~~~~~~~
>> arch/loongarch/mm/mmap.c:143:5: warning: no previous prototype for 'valid_mmap_phys_addr_range' [-Wmissing-prototypes]
143 | int valid_mmap_phys_addr_range(unsigned long pfn, size_t size)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
vim +/valid_phys_addr_range +125 arch/loongarch/mm/mmap.c
120
121 /*
122 * You really shouldn't be using read() or write() on /dev/mem. This might go
123 * away in the future.
124 */
> 125 int valid_phys_addr_range(phys_addr_t addr, size_t size)
126 {
127 /*
128 * Check whether addr is covered by a memory region without the
129 * MEMBLOCK_NOMAP attribute, and whether that region covers the
130 * entire range. In theory, this could lead to false negatives
131 * if the range is covered by distinct but adjacent memory regions
132 * that only differ in other attributes. However, few of such
133 * attributes have been defined, and it is debatable whether it
134 * follows that /dev/mem read() calls should be able traverse
135 * such boundaries.
136 */
137 return memblock_is_region_memory(addr, size) && memblock_is_map_memory(addr);
138 }
139
140 /*
141 * Do not allow /dev/mem mappings beyond the supported physical range.
142 */
> 143 int valid_mmap_phys_addr_range(unsigned long pfn, size_t size)
diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig index fcb5f9489ffd..9c36eb29096a 100644 --- a/arch/loongarch/Kconfig +++ b/arch/loongarch/Kconfig @@ -70,6 +70,7 @@ config LOONGARCH select GENERIC_LIB_CMPDI2 select GENERIC_LIB_LSHRDI3 select GENERIC_LIB_UCMPDI2 + select GENERIC_LIB_DEVMEM_IS_ALLOWED select GENERIC_PCI_IOMAP select GENERIC_SCHED_CLOCK select GENERIC_SMP_IDLE_THREAD diff --git a/arch/loongarch/include/asm/io.h b/arch/loongarch/include/asm/io.h index 999944ea1cea..398d1a7b3dd6 100644 --- a/arch/loongarch/include/asm/io.h +++ b/arch/loongarch/include/asm/io.h @@ -107,4 +107,8 @@ extern void __memcpy_fromio(void *to, const volatile void __iomem *from, size_t #include <asm-generic/io.h> +#define ARCH_HAS_VALID_PHYS_ADDR_RANGE +extern int valid_phys_addr_range(phys_addr_t addr, size_t size); +extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t size); + #endif /* _ASM_IO_H */ diff --git a/arch/loongarch/mm/mmap.c b/arch/loongarch/mm/mmap.c index 381a569635a9..71d45bdffc9e 100644 --- a/arch/loongarch/mm/mmap.c +++ b/arch/loongarch/mm/mmap.c @@ -3,6 +3,7 @@ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited */ #include <linux/export.h> +#include <linux/memblock.h> #include <linux/mm.h> #include <linux/mman.h> @@ -116,3 +117,30 @@ int __virt_addr_valid(volatile void *kaddr) return pfn_valid(PFN_DOWN(PHYSADDR(kaddr))); } EXPORT_SYMBOL_GPL(__virt_addr_valid); + +/* + * You really shouldn't be using read() or write() on /dev/mem. This might go + * away in the future. + */ +int valid_phys_addr_range(phys_addr_t addr, size_t size) +{ + /* + * Check whether addr is covered by a memory region without the + * MEMBLOCK_NOMAP attribute, and whether that region covers the + * entire range. In theory, this could lead to false negatives + * if the range is covered by distinct but adjacent memory regions + * that only differ in other attributes. However, few of such + * attributes have been defined, and it is debatable whether it + * follows that /dev/mem read() calls should be able traverse + * such boundaries. + */ + return memblock_is_region_memory(addr, size) && memblock_is_map_memory(addr); +} + +/* + * Do not allow /dev/mem mappings beyond the supported physical range. + */ +int valid_mmap_phys_addr_range(unsigned long pfn, size_t size) +{ + return !(((pfn << PAGE_SHIFT) + size) & ~(GENMASK_ULL(cpu_pabits, 0))); +}