Background memory validation for gaming devices
Various embodiments are directed to a gaming device including a background memory validation system. The background memory validation system includes a background kernel thread that validates read-only pages on the gaming device. Additionally, the background kernel thread also minimizes potential timing problems because this process only validates page content in memory that is fully-loaded and functional.
1. A method for verifying contents of one or more pages stored within a memory of a gaming device, the method comprising:
receiving a command from a memory validation module to start a background validation kernel thread,
determining whether a page is active and thereafter determining whether the active page is a read-only page;
starting the background validation kernel thread by determining a duration of a memory check cycle, wherein the duration is based on a maximum number of read-only pages to be processed during the memory check cycle or a maximum number of timer ticks before a sleep timer is initiated, thereby allowing other processes to run; and
validating the contents of one or more read-only pages stored within a memory of the gaming device with the background validation kernel thread, wherein validating the contents of the read-only pages is a background process.
2. The method of claim 1 , wherein validating the contents of one or more read-only pages further comprises determining whether a page is read-only based on one or more fields of a page table entry for the page and a virtual memory address of the page.
3. The method of claim 1 , wherein validating the contents of one or more read-only pages further comprises:
calculating a CRC32 value for the contents of the read-only page; and
comparing the calculated CRC32 value to a previously-stored CRC32 value for the contents of the read-only page.
4. The method of claim 1 , further comprising periodically requesting a status from the memory validation module.
5. A method for verifying contents of one or more pages stored within a memory of a gaming device, the method comprising:
initiating a memory validation for one or more pages stored within the memory of the gaming device, wherein the memory validation is a background process that uses a background validation kernel thread;
determining a duration of a memory check cycle using the background validation kernel thread, wherein the duration is based on a maximum number of read-only pages to be processed during the memory check cycle or a maximum number of timer ticks before a sleep timer is initiated, thereby allowing other processes to run;
determining whether a page is active and determining whether the page is a read-only page;
configuring a processing loop for the memory validation; and
validating a page is a read-only page.
6. The method of claim 5 , further comprising pausing the processing loop after a predetermined number of pages or after a predetermined time limit.
7. The method of claim 5 , further comprising periodically requesting a status from the memory validation.
8. The method of claim 5 , wherein configuring the processing loop further comprises determining a maximum number of pages processed based on a total number of pages within the gaming device and a CPU speed of the gaming device.
9. The method of claim 5 , wherein determining whether a page is read-only further comprises determining whether the page is active, has a valid virtual memory address, and whether the page is not writable.
10. The method of claim 9 , further comprising designating a page table entry for a writable page to be zero.
11. The method of claim 5 , wherein validating the read-only page further comprises:
calculating a CRC32 value for the contents of the read-only page; and
comparing the calculated CRC32 value to a previously-stored CRC32 value for the contents of the read-only page.
12. A method for verifying contents of one or more pages stored within a memory of a gaming device, the method comprising:
initiating a memory validation for one or more pages stored within the memory of the gaming device, wherein the memory validation is a background process that uses a background validation kernel thread,
determining a duration of a memory check cycle using the background validation kernel thread, wherein the duration is based on a maximum number of read-only pages to be processed during the memory check cycle or a maximum number of timer ticks before a sleep timer is initiated, thereby allowing other processes to run;
determining whether a page is active and determining whether the active page is a read-only page;
determining whether a page is active by analyzing page table entry and the virtual memory address of the page; and
validating an active page is a read-only page.
13. The method of claim 12 , further comprising configuring a processing loop for the memory validation.
14. The method of claim 13 , wherein configuring the processing loop further comprises determining a maximum number of pages processed based on a total number of pages within the gaming device and a CPU speed of the gaming device.
15. The method of claim 13 , further comprising pausing the processing loop after a predetermined number of pages or after a predetermined time limit.
16. The method of claim 12 , further comprising periodically requesting a status from the memory validation.
17. The method of claim 12 , wherein determining whether a page is read-only further comprises determining whether the page is active, has a valid virtual memory address, and whether the page is not writable.