mmio

X86 IO ports and Mmio The I/O is a channel for CPU and peripheral communication, mainly divided into two types, port I/O, and Mmio (Memory mapping I/O). The is the I/O port that we often call, and it should actually be called the I/O address space. The is accessed through the In/out directive for the x86 schema. The PC architecture has a total of 65,536 8bit I/O ports, consisting of the 64ki

Release date:Updated on: Affected Systems:XenSource Xen 4.xXenSource Xen 3.xDescription:--------------------------------------------------------------------------------Bugtraq id: 54691 Xen is an open-source Virtual Machine monitor developed by

, providing 4 GB address space for the system, that is, up to 4 GB memory can be installed. Although the 4 GB memory can be installed, the 4 GB memory space cannot all be allocated to the memory, because from the top address of the 4 GB space (FFFF_FFFFh) at the beginning, mb-1gb of address space needs to be allocated to other physical memory on the motherboard. We can see that 4 GB address space can be divided into two parts, 0 MB ~ The physical memory top address is allocated to the physical m

, because from the top address of the 4 GB space (ffff_ffffh) at the beginning, mb-1gb of address space needs to be allocated to other physical memory on the motherboard. We can see that 4 GB address space can be divided into two parts, 0 MB ~ The physical memory top address is allocated to the physical memory installed on the motherboard, 4 GB to the physical memory top address is allocated to the BIOS (ROM) and PCI/PCI-E device memory. Since these memories are basically used for system input

to solve this kind of problem is to use the perf process to sample, and then generate a flame diagram, because it is a good idea to first see where the CPU is consumed.Perf record-a-g-p 36256 sleep 20To generate a flame diagram:Win2008-badIt is clear that the majority of CPU consumption is KVM operation, the most important consumption is vmx_handle_exit. (The real flame diagram is a vector diagram, which is easy to check with a browser). There are two main causes of Vmx_handle_exit:• Access io

(order:4, 65536 bytes)??TCP established hash table entries:65536 (order:7, 524288 bytes)TCP bind hash Table entries:65536 (order:6, 262144 bytes)Tcp:hash tables configured (established 65536 bind 65536)TCP Reno RegisteredNet:registered Protocol Family 1Checking if image is initramfs...it isn ' t (no cpio magic); Looks like an initrdFreeing Initrd memory:22757k freedJFFS2 version 2.2. (NAND) (SUMMARY)? 2001-2006 Red Hat, Inc.Msgmni have been set to 1009IO Scheduler NoOp registered (default)Seria

The topic of this article:Overview of IO VirtualizationDevice Discovery access interception device analog device sharingSoftware-based IO virtualizationIO virtualization based on front-end backendHardware-based IO virtualizationOverviewFrom the processor's point of view, peripherals are accessed through a set of I/O resources (port I/O or Mmio), so the associated virtualization of the device is called I/O virtualization. The idea is that VMM intercept

be readable.-Writing must be idempotent, ordering-independent and access-size-independent.-Writing back a read value must be safe and side-effect-free.-Any side effects due to a write can be delayed until the data is explicitlyFlushed by software. Anything else will lead to data loss (read: Upload uption) or other "very weird ",Unpredictable things will happen.Regular memory is cache coherent, and DMA (with a few very special casesException that are beyond the scope of this document) is cache c

driver Hub Va = 0xffc00000, Pa = 0x30380000, size = 0x00027000 Netwinder floating point emulator v0.97 (Double Precision) Devfs: Richard Gooch (rgooch@atnf.csiro.au) Devfs: boot_options: 0x1 NTFS Driver 2.1.15 [flags: R/W]. Yaffs Mar 6 2008 10:21:10 installing. Console: switching to color frame buffer device 40x30 S3c2410ts init S3c2410ts Device Driver Major: 253 S3c2410ts initialized S3C2410 real time clock driver v0.1 S3C2410X serial, (c) 2003 simtec Electronics Ttys0 at

command is not updated after execution boot.img Print the log In search Earlyprink/earlycon/bootconsoles, see a print Found in the program: The reason is only cmdline+ earlyprintk, but not to Earlyprink assignment if (!BUF) { Pr_warning ("No earlyprintk arguments passed.\n"); return 0; } Kernel-parameters.txt is described in the following earlycon= [KNL] Output early console device and options. Uart[8250],io,Uart[8250],mmio,Uart[8250],mmi

The qemu memory API simulates the qemu memory, I/O bus, and the corresponding controller. It mainly includes the following simulation parts:• Regular memory• Io ing memory (mmio)• Memory controller (dynamically ing physical memory to different virtual address spaces) The qemu memory model provides the following functions:• Tracks memory changes on the target machine• Coalesced memory)• Create ioeventfd regions for KVMThe memory of qemu is organized in

accessed with the address, pointer. However, for the Linux kernel, it may be used for different CPUs, so it must be considered in both ways, so it takes a new approach, the I/O map-based or memory-mapped I/O port is known as an I/O region (I/O regions), regardless of which way you use, Must first apply IO area: Request_resource (), release it at the end: Release_resource ().Io region is an IO resource, so it can be described using the resource structure type.There are 2 ways to access the IO po

disabled, data cache writebackBuilt 1 zonelists in Zone order, mobility grouping on. Total pages: 109728Kernel command line: Console = ttymxc0, 115200 init =/init androidboot. Console = ttymxc0 di1_primary calibration IP = DHCPUnknown boot option 'androidboot. Console = ttymxc0 ': ignoringPID hash table entries: 2048 (Order: 11,819 2 bytes)Dentry cache hash table entries: 65536 (Order: 6, 262144 bytes)Inode-Cache hash table entries: 32768 (Order: 5, 131072 bytes)Memory: 432 MB = 432 MB totalMem

(MMIO) GAP specificationLinux-based device manufacturers use MMIO gap (also known as PCI Hole) to allocate available physical memory between the Just enough Operating System (JeOS) used to boot the device and the actual software infrastructure of the drive device. Inability to configure MMIO gap causes JeOS to run out of all available memory, making the device's

driver usbfsusbcore:registered new interface driver Hubusbcore:regist Ered new device driver Usbromfs MTD (C) Red Hat, Inc.io Scheduler NoOp Registeredio Scheduler deadline Registeredio s Cheduler CFQ registered (default) Start plist testend plist tests3c-fb s3c-fb:window 0:fbserial:8250/16550 driver, 4 por TS, IRQ sharing disableds3c6400-uart.0:ttysac0 at MMIO 0x7f005000 (IRQ = in) is a s3c6400/10console [ttySAC0] Enableds3c6 400-uart.1:ttysac1 at

layer losts interrups, and don ' t know why!!!+if (Pin_val1 = = 0 | | ntries > Nr_tries)+return irq_handled;+ #undef nr_tires+ #endif 6, if the boot detection succeeds, the add port succeeds and will print: Serial8250.11:ttys0 at MMIO 0x30000000 (IRQ = $) is a 16550aserial8250.11: TtyS1 at MMIO 0x30000008 (IRQ = up) is a 16550aserial8250.11:ttys2 at MMIO 0x30000

because DMA uses physical addresses to access memory, does not go through the MMU, and requires a contiguous buffer, so in order to provide a physically contiguous buffer, a region must be specifically partitioned from the physical address space for DMA. 16m-896m Zone_normal, the physical page of this area is the kernel direct mapping, that is, kernel space commonly used data such as kernel code, GDT, IDT, PGD, Mem_map array and so on zone_normal, in order to kernel the virt

6550 driver $ revision: 1.90 $4 ports, IRQ sharing enableds3c2440-uart.0: s3c2410_serial0 at mmio 0x50000000 (IRQ = 70) is a S3C2440s3c2440-uart.1: s3c2410_serial1 at mmio 0x50004000 (IRQ = 73) is a S3C2440s3c2440-uart.2: maid at mmio 0x50008000 (IRQ = 76) is a s3c2440ramdisk driver initialized: 16 RAM disks of 4096 K size 1024 blocksizeloop: module loadeddm9000

Precision)Ms gmni has been set to 120Io scheduler Noop registeredIo scheduler anticipatory registered (default)Io scheduler deadline registeredIo scheduler CFQ registeredConsole: switching to color frame buffer device 30x40Fb0: s3c2410fb Frame Buffer DeviceS3c2440-uart.0: s3c2410_serial0 at mmio 0x50000000 (IRQ = 70) is a S3C2440S3c2440-uart.1: s3c2410_serial1 at mmio 0x50004000 (IRQ = 73) is a S3C2440S3c2

executed (except for invlpg, load, and changing the related bit of Cr4 will also cause TLBFlush ). Therefore, the virtual machine only needs to intercept these commands and update the corresponding address translation relationship to vtlb. For example, if the guest OS needs to flush the VA in TLB as 0x11111111, what hypervisor needs to do is to find the physical address PA corresponding to 0x11111111 In the guest OS page table, then, convert the created p2m table (Pa => Ma) to Ma, and fill in v