Re: [uClinux-dev] About system call code in arm-uclinux, Aplio version

From: Joe deBlaquiere (jadb@redhat.com)
Date: Sun Jan 21 2001 - 10:29:31 EST 

I'm not entirely sure about this, but I think the answer to this is that
the kernel_thread() call creates a thread which runs as a user mode
process (using the clone call). Therefore init() is not being run in SVC
mode.

Zhu, Yaozong wrote:

> Hi all,
> 	It seems that start_kernel(init/main.c) runs in SVC mode.  And in start_kernel, kernel_thread(init, NULL, 0) is called which does two swi's .   My humble question is ,  when doing system calls from SVC mode, vector_swi(arch/armnommu/kernel/entry-armv.S) saves and restores USER mode registers, and _ret_from_sys_call does restore sp_SVC and spsr_SVC, but lr_SVC is lost, isn't this a problem,  or I am wrong?
> 
> 
> 
> 
> This message resent by the uclinux-dev@uclinux.org list server http://www.uClinux.org/


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Joe deBlaquiere
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