18–20 Sept 2024
Europe/Vienna timezone

Poison & remedy of vmas instead of guards

20 Sept 2024, 15:45
15m
"Hall L1" (Austria Center)

"Hall L1"

Austria Center

135
Kernel Memory Management MC Kernel Memory Management MC

Speakers

Liam Howlett (Oracle) Lorenzo Stoakes (Oracle)

Description

vma guards are inserted at the start and/or end of vmas to detect out-of-bound reads or writes. Currently these guards are represented by an allocated vma even though almost all the information in the vma is not used. Sometimes these guards are so numerous that they represent close to half of the vmas used in a system. Such a large number of underutilized objects represents a potential for significant space savings. I would like to discuss a more efficient way to implement the same functionality using "poison" and "remedy", which will jilt the vma guards from the next generation of allocators.

Primary author

Co-author

Presentation materials