linux-kernel

问题 I have developped a kernel module to manage a nf4 tag as a char device. I have developped this module outside of the kernel and tested it compiled as a loadable kernel module (i.e. .ko) during the development phase. Once the driver has been functional and stable enough I have inserted it into linux kernel source (v4.9.30) using patches so it's built as part of the kernel. Here I'm in the situation where the module is loaded probed at boot by kernel as it's builtin and it appears into the

问题 I have developped a kernel module to manage a nf4 tag as a char device. I have developped this module outside of the kernel and tested it compiled as a loadable kernel module (i.e. .ko) during the development phase. Once the driver has been functional and stable enough I have inserted it into linux kernel source (v4.9.30) using patches so it's built as part of the kernel. Here I'm in the situation where the module is loaded probed at boot by kernel as it's builtin and it appears into the

问题 I have developped a kernel module to manage a nf4 tag as a char device. I have developped this module outside of the kernel and tested it compiled as a loadable kernel module (i.e. .ko) during the development phase. Once the driver has been functional and stable enough I have inserted it into linux kernel source (v4.9.30) using patches so it's built as part of the kernel. Here I'm in the situation where the module is loaded probed at boot by kernel as it's builtin and it appears into the

问题 I have developped a kernel module to manage a nf4 tag as a char device. I have developped this module outside of the kernel and tested it compiled as a loadable kernel module (i.e. .ko) during the development phase. Once the driver has been functional and stable enough I have inserted it into linux kernel source (v4.9.30) using patches so it's built as part of the kernel. Here I'm in the situation where the module is loaded probed at boot by kernel as it's builtin and it appears into the

问题 The below manual on system() says it blocks SIGINT and SIGQUIT signal for any binary program run through system() call. https://man7.org/linux/man-pages/man3/system.3.html#:~:text=The%20system()%20library%20function,the%20command%20has%20been%20completed. Psedo Code: thread_1() { ... system("binary application"); } main() { ... pid = pthread_create(thread_1); pthread_cancel(pid); } pthread_cancel issues SIGINT to thread 1 which kill the thread 1, but not the binary application. How to make

问题 I am looking scheduling algorithm in static void __sched notrace __schedule(bool preempt) (__schedule) Along the way, I find # define __percpu __attribute__((noderef, address_space(3))) (address_space) However, I cannot understand why struct address_space can be initialized by using round brackets ( ) since I look through struct syntax in c language. How to initialize a struct in accordance with C programming language standards. struct should be initialized by { } for each filed. So, what

问题 I'm trying to get all the mount points in a kernel module. Below is what I've come up with. It segfaults because of the strcat. Is this the correct way to get the mount points? Will this work? if so how do i fix the segfault? If not, how does one go about getting the mount points in a linux kernel module? I've tried cycle the whole namespace looking for mountpoint roots that match but its from 2003 and the kernel has changed so much so its basically useless. Also tried get filesystem mount

问题 I'm trying to get all the mount points in a kernel module. Below is what I've come up with. It segfaults because of the strcat. Is this the correct way to get the mount points? Will this work? if so how do i fix the segfault? If not, how does one go about getting the mount points in a linux kernel module? I've tried cycle the whole namespace looking for mountpoint roots that match but its from 2003 and the kernel has changed so much so its basically useless. Also tried get filesystem mount

问题 I'm confused of user/kernel thread and mode/context switch (Platform: Linux) I have two linked questions. (1) Is the below sentence right? If I make a system call, then mode switch (user mode to kernel mode) will occur and eventually switching from user thread to kernel thread happens. Since system call can only be executed in kernel thread, I think mode switch must occur the switching from the user thread to kernel thread. (2) Then, what we call the overhead of mode switching is that

问题 I'm confused of user/kernel thread and mode/context switch (Platform: Linux) I have two linked questions. (1) Is the below sentence right? If I make a system call, then mode switch (user mode to kernel mode) will occur and eventually switching from user thread to kernel thread happens. Since system call can only be executed in kernel thread, I think mode switch must occur the switching from the user thread to kernel thread. (2) Then, what we call the overhead of mode switching is that