Messages in this thread |  | | Date | Tue, 20 Nov 2001 20:54:42 +0000 (WET) | From | Luis Miguel Correia Henriques <> | Subject | copy to user |
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The reason that I need it to spend CPU time is that I'm developing a fault injector. The purpose of a fault injection tool is, as you could imagine, to test some critical systems and it's capacity to recover from fails. The reason for changing the code of a process is that process must be delayed but without leaving the CPU - everything must look like nothing wrong is happening, except for other processes that are waiting for something from the delayed process...
Maybe I should have explained this before... sorry.
I suppose now you can understand why SIGSTOP won't work. Hope you can help me :)
About using udelay... this soluction seemed fine to me at first but if I hang the CPU with udelay the scheduler will no be doing it's job (isn't it?). This would give me even more intrusiveness (another requirement: the less intrusiveness as possible).
Isn't there any doubt that copy_to_user can handle my problem? When I use it to change CS, this function returns the correct number of bytes (and no error) but, when I try to read... the old data is still there. I suppose there is a page/segment protection against writing to CS, isn't it?
Luis Henriques
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