On 2017/5/2 16:43, Michal Hocko wrote: > On Tue 02-05-17 15:59:23, Xishi Qiu wrote: >> Hi, I use "memtester -p 0x6c80000000000 10G" to test physical address 0x6c80000000000 >> Because this physical address is invalid, and valid_mmap_phys_addr_range() >> always return 1, so it causes crash. >> >> My question is that should the user assure the physical address is valid? > > We already seem to be checking range_is_allowed(). What is your > CONFIG_STRICT_DEVMEM setting? The code seems to be rather confusing but > my assumption is that you better know what you are doing when mapping > this file. > HI Michal, CONFIG_STRICT_DEVMEM=y, and range_is_allowed() will skip memory, but 0x6c80000000000 is not memory, it is just a invalid address, so it cause crash. You mean the user should assure the physical address is valid, right? Thanks, Xishi Qiu >> ... >> [ 169.147578] ? panic+0x1f1/0x239 >> [ 169.150789] oops_end+0xb8/0xd0 >> [ 169.153910] pgtable_bad+0x8a/0x95 >> [ 169.157294] __do_page_fault+0x3aa/0x4a0 >> [ 169.161194] do_page_fault+0x30/0x80 >> [ 169.164750] ? do_syscall_64+0x175/0x180 >> [ 169.168649] page_fault+0x28/0x30 >> >> Thanks, >> Xishi Qiu > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
