I write a new device driver which is using a reserved-memory area. Where I followed the description from https://xilinx-wiki.atlassian.net/wiki/spaces/A/pages/18841683/Linux+Reserved+Memory The memory reservation in the device tree works as expected. But now I'm curious about the address mapping in the device driver. In the prob function I use "memremap()" to get the reserved area remapped into the virtual memory area of the kernel space (and later on into user space). Later I work with the virtual address returned from "memremap()", for that and to understand the kernel functions, I used "virt_to_phys()" function to convert the vaddr back to the physical address. Unfortunately, I don't get the same physical address back. What is wrong there? Or what do I miss? I see a delta of 0x847000 bytes when convert the address back, so where do this come from? Here is a code sequence used: paddr = r.start; vaddr = memremap(paddr, 4096, MEMREMAP_WB); printk("Allocated reserved memory, vaddr: 0x%0X, paddr: 0x%0X\n", (u32)vaddr, paddr); printk("Allocated reserved memory, paddr (2): 0x%0x\n", virt_to_phys(vaddr)); where the output is [10370.743577] Allocated reserved memory, vaddr: 0xE0847000, paddr: 0x20000000 [10370.750564] Allocated reserved memory, paddr (2): 0x20847000
