17.12.2. virt_to_phys
Convert a virtual address to physical:
insmod virt_to_phys.ko cat /sys/kernel/debug/lkmc_virt_to_phys
Source: kernel_modules/virt_to_phys.c
Sample output:
*kmalloc_ptr = 0x12345678 kmalloc_ptr = ffff88000e169ae8 virt_to_phys(kmalloc_ptr) = 0xe169ae8 static_var = 0x12345678 &static_var = ffffffffc0002308 virt_to_phys(&static_var) = 0x40002308
We can confirm that the kmalloc_ptr translation worked with:
./qemu-monitor 'xp 0xe169ae8'
which reads four bytes from a given physical address, and gives the expected:
000000000e169ae8: 0x12345678
TODO it only works for kmalloc however, for the static variable:
./qemu-monitor 'xp 0x40002308'
it gave a wrong value of 00000000.
Bibliography: