Ptrace implementation

Ptrace implementation

[Erik Kooistra]

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Hello,

I am porting http://hetgrotebos.org/wiki/Tracy to sparc on linux. But i encounters some issues, If i read the sys call docs correctly the sycall number is stored in, G1, but from my tests it seems it is stored in G0.

Second, the syscall_restore function is not implemented, see http://lxr.free-electrons.com/source/arch/sparc/include/asm/syscall.h powerpc and x86/amd64 use a orig_ register. Maybe this is also a desirable solution for sparc ??

finally, i can't seem to find the result of the sys call in the registers. Powerpc has solved this by adding a result to the pt_regs struct, (the result should be in the o0 if i am correct).

(I am currently working on a sparc v100 with a TI UltraSparc IIe (Hummingbird))

Erik Kooistra

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Re: Ptrace implementation

[David Miller]

From: Erik Kooistra <me@erikkooistra.nl>
Date: Sun, 2 Mar 2014 15:48:09 +0100

> but from my tests it seems it is stored in G0.

%g0 is the "zero register, writes to it are ignored and all reads give
zero.