Hello,
Looking at the vmdump code, here is something that puzzles me.
I'm not sure if I'm missing something obvious here.
Since right now dump involves wait_kio calls, which involves a context
switch to another runnable process, isn't there a chance of the memory
state changing whilst the dump is going on. Couldn't the dump become
inconsistent, or not correctly reflect the state of the system when the
incident that triggered the dump happened ? (Since interrupts aren't turned
off, even that could affect the state ... but to a lesser extent, I guess)
I had actually started with looking into the smp_send_stop issue and the
more generic issue of getting a consistent system snapshot (as accurately
reflecting the state at the time of the system crash as possible), when
this question came to mind. BTW, is there some work going on in this area ?
Or have the issues been sorted out already ?
Matt you had mentioned that you were working on a specialized IDE driver
for dump, to avoid having to go through the normal kio/raw i/o path in the
kernel. Is that still in the plan ?
Regards
Suparna
Suparna Bhattacharya
IBM Software Lab, India
E-mail : bsuparna@xxxxxxxxxx
Phone : 91-80-5267117, Extn : 2525
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