Method and computer system for accessing memory

Abstract

The present invention discloses a memory access method and a computer system. A peer mapping area of a kernel mode comprises a first peer mapping sub-area and a second peer mapping sub-area, wherein the first peer mapping sub-area and the second peer mapping sub-area have different page tables, and an original system task and an original kernel task use a virtual address of the first peer mapping sub-area to access a physical memory. The method comprises: when a being-monitored kernel task using a virtual address of the second peer mapping sub-area to make a request to access the corresponding physical memory, determining whether conversion of the page table is normal according to a present-bit in the page table of the second peer mapping sub-area; under the condition that the page table is abnormally converted, triggering abnormity of a missing page, and carrying out a processing procedure of the abnormity of the missing page; and and under the condition that the page table is normally converted, accessing the physical memory. Embodiments of the present invention can avoid an influence caused by unauthorized access of the kernel mode memory, so that the system reliability is improved, and the frequency of system crash is effectively reduced.

Description

technical field [0001] The invention relates to the field of computers, in particular to a method for accessing memory and a computer system. Background technique [0002] Reliability, Availability, Serviceability (RAS for short) feature is an important feature of a high-end server at present. According to statistics, one minute of downtime will cause the industry to lose tens or even millions of dollars. Therefore, the high reliability of the system is a very important indicator. For example, when the reliability indicator is 99.999%, it means that after one year Downtime does not exceed 5 minutes. [0003] If the business only involves the user mode, illegal memory access will generally cause a segment fault (segmentfault) to terminate the program, which only affects the business itself and will not interfere with the kernel mode. Currently, the kernel's page fault mechanism can detect illegal access caused by page faults in user mode. [0004] The memory at the kernel ...

AI Technical Summary

Problems solved by technology

For example, some low-quality third-party software (such as drivers, feature modules, etc.) may cause page faults in the kernel state due to illegal access to memory, access to illegal addresses, etc., and eventually cause system crashes and crashes

For example, in the field of mobile phones and other terminals, due to the uneven quality of developed applications, it often leads to flashbacks, system restarts, etc.

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