arno/linux-insides
1
0
Fork 0
mirror of https://github.com/0xAX/linux-insides.git synced 2025-08-04 22:25:17 +00:00
Code Issues Releases Wiki Activity

Merge pull request #864 from cyyzero/fix_segment_descriptor

Browse Source 
Fix misdescription about conforming bit
This commit is contained in:
Alex Kuleshov 2025-07-28 13:28:46 +05:00 committed by GitHub
commit ac6c11993c
No known key found for this signature in database
GPG Key ID: B5690EEEBB952194
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
Booting/linux-bootstrap-2.md
View File

@ -127,7 +127,7 @@ As we can see the first bit(bit 43) is `0` for a _data_ segment and `1` for a _c
* if E(bit 42) is 0, expand up, otherwise, expand down. Read more [here](http://www.sudleyplace.com/dpmione/expanddown.html).
* if W(bit 41)(for Data Segments) is 1, write access is allowed, and if it is 0, the segment is read-only. Note that read access is always allowed on data segments.
* A(bit 40) controls whether the segment can be accessed by the processor or not.
* C(bit 43) is the conforming bit(for code selectors). If C is 1, the segment code can be executed from a lower level privilege (e.g. user) level. If C is 0, it can only be executed from the same privilege level.
* C(bit 42) is the conforming bit(for code selectors). If C is 1, the segment code can be executed from a lower level privilege (e.g. user) level. If C is 0, it can only be executed from the same privilege level.
* R(bit 41) controls read access to code segments; when it is 1, the segment can be read from. Write access is never granted for code segments.
4. DPL[2-bits] (Descriptor Privilege Level) comprises the bits 45-46. It defines the privilege level of the segment. It can be 0-3 where 0 is the most privileged level.