BACKGROUND Malicious code, known as malware, which includes viruses, worms, adware, etc., may attack core components of the operating system to compromise key applications, including critical applications that operate in the operating system kernel,…

A program's memory usage typically includes four different regions: Code -- The region where the program instructions are stored. Static memory -- The region where global variables (variable defined outside any function) as well as static local varia…

https://flink.apache.org/news/2015/09/16/off-heap-memory.html   Running data-intensive code in the JVM and making it well-behaved is tricky. Systems that put billions of data objects naively onto the JVM heap face unpredictable OutOfMemoryErrors and…

The computer program memory is organized into the following: Data Segment (Data + BSS + Heap) Stack Code segment Data The data area contains global and static variables used by the program that are explicitly initialized with a non-zero (or non-NULL)…

1 main.c #include "led.h" #define BASE_ADDRESS (volatile datum *) 0x10000000 #define NUM_BYTES 0x10000 /********************************************************************** * * Function: main() * * Description: Test the second 64 KB bank of SR…

1 MEMORY command The MEMORY command describes the location and size of blocks of memory in the target. You can use it to describe which memory regions may be used by the linker, and which memory regions it must avoid. A linker script may contain at m…

Memory management is the heart of operating systems; it is crucial for both programming and system administration. In the next few posts I'll cover memory with an eye towards practical aspects, but without shying away from internals. While the concep…

Memory dump是系统出现crash时常用的分析故障原因的方法,qualcomm 各子系统运行时,为方便debug,都会开辟ram log和debug variable用于保存各系统运行信息及健康状态,就像飞机黑盒子用于记录飞行器飞行状态.当出现crash时,可以将ram log .debug variable所在的memory region dump出来分析导致故障的原因.所以当需要分析crash故障.功耗问题等,qualcomm都会要求客户提供正确的memory dump.Memory…

Memory management is the heart of operating systems; it is crucial for both programming and system administration. In the next few posts I'll cover memory with an eye towards practical aspects, but without shying away from internals. While the concep…

kmalloc #include <linux/slab.h> void *kmalloc(size_t size,int flags); void kfree(void *addr); flags: GFP_ATOMIC: Used to allocate memory from interrupt handlers and other code outside of a process context.Never sleeps GFP_KERNEL: Normal allocation o…