Fix

content/posts/2023-11-11-Linux-Kernel-sys_fork.md

@@ -1,11 +1,11 @@
 ---
 title: Linux Kernel, syscalls
-date: 2022-11-19T
+date: 2023-11-11T01:22:30Z
 slug: linux-kernel-sys-fork
 description: ""
 ---
 
-#### sys_fork()
+### sys_fork()
 
 ```asm
 .align 2
@@ -23,7 +23,7 @@ _sys_fork:
 1:  ret
 ```
 
-##### `FUNCTION find_empty_process()`
+#### `FUNCTION find_empty_process()`
 
 ```assembly
 A:
@@ -49,11 +49,12 @@ A:
 
 
 
-##### `FUNCTION copy_process`
-
-`<- nr, EBP, EDI, ESI, GS, EBX~EDX, CS~FS, EIP, EFLAGS, ESP, SS`
-`-> INT`
+#### `FUNCTION copy_process`
 
+```
+<- nr, EBP, EDI, ESI, GS, EBX~EDX, CS~FS, EIP, EFLAGS, ESP, SS
+-> INT
+```
 
 ```assembly
 TASK_STRUCT P
@@ -117,24 +118,15 @@ RET last_pid
 
 
 
-"nr" passed is the index of the new task in the task array, where each element corresponds to a process slot.
-
-fork() copies the parent's kernel context, as well as general registers and segment selectors required for a new process to run in user space.
-
-It creates a new task structure from a new free page and sets up default values and certain parameters inherited from the parent, such as process ID, priority, and execution times.
-
-Then it copies memory regions from the parent to the new process, referred to by "nr," which is the index of the new process in the task array.
-
-Changes the parent process's working directory (PWD) and root directory reference counters, incrementing them by 1 to reflect the new child process now also using these resources.
-
-Sets the Task State Segment (TSS) and Local Descriptor Table (LDT) entries, which are x86-specific structures used for task switching and memory segmentation, respectively.
-
-TSS holds information about the task's stack for privilege level changes and also the hardware context when a task switch occurs.
-
-LDT is a segment descriptor table that stores descriptors for local segments, giving a task its own set of segment registers.
-
-Finally, it assigns the newly created task structure, p, to the task array at index "nr." This effectively makes the new task available for scheduling.
-
-
+- "nr" passed is the index of the new task in the task array, where each element corresponds to a process slot.
+- fork() copies the parent's kernel context, as well as general registers and segment selectors required for a new process to run in user space.
+- It creates a new task structure from a new free page and sets up default values and certain parameters inherited from the parent, such as process ID, priority, and execution times.
+- Then it copies memory regions from the parent to the new process, referred to by "nr," which is the index of the new process in the task array.
+- Changes the parent process's working directory (PWD) and root directory reference counters, incrementing them by 1 to reflect the new child process now also using these resources.
+- Sets the Task State Segment (TSS) and Local Descriptor Table (LDT) entries, which are x86-specific structures used for task switching and memory segmentation, respectively.
+- TSS holds information about the task's stack for privilege level changes and also the hardware context when a task switch occurs.
+- LDT is a segment descriptor table that stores descriptors for local segments, giving a task its own set of segment registers.
+- Finally, it assigns the newly created task structure, p, to the task array at index "nr." This effectively makes the new task available for scheduling.
 
+### `_sys_fork()`
 "sys_fork" finds an empty process ID using the search loop in `_find_empty_process`, then it invokes `_copy_process` to clone the parent's kernel context to the new process. This sets up a complete environment for the new process to run independently from the parent, but initially as a nearly identical copy.

scripts/remote.sh

@@ -1 +1,8 @@
-ssh web /srv/blog/scripts/update.sh
+HOST=$1
+if [[ -z $1 ]];
+then
+    HOST="web"
+    echo $HOST
+fi
+
+ssh $HOST /srv/blog/scripts/update.sh