Linux Kernel -- IRQ (proc file system VS system call) -


i working on linux kernel project. in project modified kernel copy_process called 1 of modules responds writes proc file entry. in essence, things liks:

int procfile_write(struct file *file, const char *buffer, unsigned long count,            void *data) {     //...more code     copy_process(...);     //...more code }  int init_module() {     /* create /proc file */     our_proc_file = create_proc_entry(procfs_name, 0644, null);     // more code     our_proc_file->write_proc = procfile_write;     return 0;   /* ok */ }

my problem kernel hangs inside copy_process when hits line: 

write_lock_irq(&tasklist_lock);

now, know function being called time do_fork. happens inside system call.

my questions:

  1. am on right path thinking has writing proc file entry vs system calls?
  2. what irqs have writing proc file entries?
  3. is writing proc file entry different system call? mean in way handled , in context invoked?

thank you!

update: converted way code called being called while handling write proc file being called system call. nothing changed. still hangs when getting same line (i.e. locking tasklist_lock). now, problem why hangs there? , how fix issue?


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