Kernel DSO ?

[Mulyadi Santosa]

On Tue, Feb 5, 2013 at 9:13 AM, Shraddha Kamat <sh2008ka at gmail.com> wrote:
> What is a kernel DSO ? I encountered it while
> I was reading perf code.

AFAIK, it's a virtual "library", which act as a "hub" when user space
application does system call.

Specifically, when one does system call, it jumps to this DSO. Then,
IIRC, this DSO determines whether to use int 80h or sysenter/syscall
(for x86). Following it up, system call flows as usual.

You can see this DSO's address by using cat /proc/self/maps. Look for "vdso".

-- 
regards,

Mulyadi Santosa
Freelance Linux trainer and consultant

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