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<TITLE>RE: kdump info request</TITLE>
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<P><FONT SIZE=2>Thanks for the reply. I guess we have pretty much nailed down device bringup sequence when loading under capture kernel. Our concern is: the capture kernel has a significant smaller memory footprint. Our RAID driver itself has a large memory requirement, some of which could fail allocation when loaded under the capture kernel.<BR>
<BR>
If we could somehow determine that we are being called in context of capture kernel, we can dynamically lower driver memory requirement (at cost of lower IO throughout of-course, which is ok for this brief context).<BR>
<BR>
Thanks<BR>
-Atul<BR>
<BR>
-----Original Message-----<BR>
From: Vivek Goyal [<A HREF="mailto:vgoyal@in.ibm.com">mailto:vgoyal@in.ibm.com</A>]<BR>
Sent: Tue 9/18/2007 9:53 PM<BR>
To: Mukker, Atul<BR>
Cc: vgoyal@in.ibm.com; Kexec Mailing List<BR>
Subject: Re: kdump info request<BR>
<BR>
On Tue, Sep 18, 2007 at 03:13:42PM -0600, Mukker, Atul wrote:<BR>
> Hello Vivek, Hari:<BR>
><BR>
> <BR>
><BR>
> Excuse me for contacting you direct, but seems like you 2 can point me<BR>
> to a right direction for a kdump question we have.<BR>
><BR>
> <BR>
><BR>
> We are trying to make sure our RAID driver works ok when kernel is<BR>
> loaded with kdump. Is there a way for driver to detect this condition;<BR>
> that is, current kernel is running with kdump. We need this information<BR>
> so we can scale down certain operations in the driver.<BR>
><BR>
<BR>
Hi Atul,<BR>
<BR>
What do you mean by detecting if current kernel is running with kdump? Do<BR>
you mean that you want to know the moment somebody loads a capture kernel<BR>
by kexec -p and driver will change some of its behaviour?<BR>
<BR>
I think that's not the right way to go about. Explain the issue<BR>
a little bit in detail.<BR>
<BR>
Generally drivers run into issues while initializing in second kernel and<BR>
one of the way to handle it is reset the device before going further with<BR>
initialization. I am hoping your RAID controller provides some kind of<BR>
reset mechanism from software.<BR>
<BR>
Thanks<BR>
Vivek<BR>
<BR>
<BR>
</FONT>
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