diff --git a/README.md b/README.md
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 # rCore-Tutorial-v3
-rCore-Tutorial version 3.x
+rCore-Tutorial version 3.5. See the [Documentation in Chinese](https://rcore-os.github.io/rCore-Tutorial-Book-v3/).
+
+## news
+- 2021.07.29: Now we are updating our labs. Please checkout chX-dev Branches for our current new labs. (Notice: please see the [Dependency] section in the end of this doc)
+
+## Overview
+
+This project aims to show how to write an **Unix-like OS** running on **RISC-V** platforms **from scratch** in **[Rust](https://www.rust-lang.org/)** for **beginners** without any background knowledge about **computer architectures, assembly languages or operating systems**.
+
+## Features
+
+* Platform supported: `qemu-system-riscv64` simulator or dev boards based on [Kendryte K210 SoC](https://canaan.io/product/kendryteai) such as [Maix Dock](https://www.seeedstudio.com/Sipeed-MAIX-Dock-p-4815.html)
+* OS
+  * concurrency of multiple processes
+  * preemptive scheduling(Round-Robin algorithm)
+  * dynamic memory management in kernel
+  * virtual memory
+  * a simple file system with a block cache
+  * an interactive shell in the userspace
+* **only 4K+ LoC**
+* [A detailed documentation in Chinese](https://rcore-os.github.io/rCore-Tutorial-Book-v3/) in spite of the lack of comments in the code(English version is not available at present)
+
+## Run our project
+
+TODO:
+
+## Working in progress
+
+Now we are still updating our project, you can find latest changes on branches `chX-dev` such as `ch1-dev`. We are intended to publish first release 3.5.0 after completing most of the tasks mentioned below.
+
+Overall progress: ch7
+
+### Completed
+
+* [x] automatically clean up and rebuild before running our project on a different platform
+* [x] fix `power` series application in early chapters, now you can find modulus in the output
+* [x] use `UPSafeCell` instead of `RefCell` or `spin::Mutex` in order to access static data structures and adjust its API so that it cannot be borrowed twice at a time(mention `& .exclusive_access().task[0]` in `run_first_task`)
+* [x] move `TaskContext` into `TaskControlBlock` instead of restoring it in place on kernel stack(since ch3), eliminating annoying `task_cx_ptr2`
+* [x] replace `llvm_asm!` with `asm!`
+* [x] expand the fs image size generated by `rcore-fs-fuse` to 128MiB
+* [x] add a new test named `huge_write` which evaluates the fs performance(qemu\~500KiB/s k210\~50KiB/s)
+* [x] flush all block cache to disk after a fs transaction which involves write operation
+
+### Todo(High priority)
+
+* [ ] bug fix: we should call `find_pte` rather than `find_pte_create` in `PageTable::unmap`
+* [ ] bug fix: check validity of level-3 pte in `find_pte` instead of checking it outside this function
+* [ ] use old fs image optionally, do not always rebuild the image
+* [ ] replace `spin::Mutex` with `UPSafeCell` before SMP chapter
+* [ ] add new system calls: getdents64/fstat
+* [ ] shell functionality improvement(to be continued...)
+* [ ] add a new chapter about synchronization & mutual exclusion(uniprocessor only)
+* [ ] give every non-zero process exit code an unique and clear error type
+* [ ] effective error handling of mm module
+
+### Todo(Low priority)
+
+* [ ] rewrite practice doc and remove some inproper questions
+* [ ] provide smooth debug experience at a Rust source code level
+* [ ] format the code using official tools
+* [ ] support Allwinner's RISC-V D1 chip
 
 ## Dependency
 
 ### Binaries
 
-* rustc 1.56.0-nightly (08095fc1f 2021-07-26)
+* rustc 1.56.0-nightly (b03ccace5 2021-08-24)
 
 * qemu: 5.0.0
 
-* rustsbi-lib: 0.2.0-alpha.4
+* rustsbi: qemu[7d71bfb7] k210[563144b0]
 
-  rustsbi-qemu: d4968dd2
+### Crates
 
-  rustsbi-k210: b689314e
+We will add them later.
diff --git a/dev-env-info.md b/dev-env-info.md
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+# rCore-Tutorial-v3
+rCore-Tutorial version 3.x
+
+## Dependency
+
+### Binaries
+
+* rustc 1.56.0-nightly (08095fc1f 2021-07-26)
+
+* qemu: 5.0.0
+
+* rustsbi-lib: 0.2.0-alpha.4
+
+  rustsbi-qemu: d4968dd2
+
+  rustsbi-k210: b689314e