Thank you for your reply. it's interesting, my modified kernel image is run ok on my hardware(arm926ejs). i test mounting ramfs and nfs, they are all ok. are they occasional? sorry, i don't comprehend your explanation about it In my opinion, if it's possible that the content of parameters isn't in memory at the time of the call, the "sys_mount" can't get them also. could u explain it in detail? Thanks Thanks. sean -----邮件原件----- 发件人: Rajat Jain [mailto:Rajat.Jain@xxxxxxxxxxxx] 发送时间: 2009年10月20日 16:48 收件人: 付新荣; kernelnewbies@xxxxxxxxxxxx 主题: RE: About the system call named "sys_mount". Hi, > now, i want to simplify the function according to the following > method, but i don't know wether there is some potential risk. > 1. don't to allocates memory in kernel space for each parameter. > 2. sys_mount refer to the parameter through the memory pointer passed > directly. You can't refer to a user space memory directly. The reason being it could not be in memory at the time of the call (and the kernel cannot page fault). And thus the copy to kernel space is justified and needed. Thanks, Rajat -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
