linux-kernel - Re: [PATCH V15 03/11] cper: add timestamp print to CPER status printing

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Message-ID: <20170421172603.4574wonnm5tgvbcn@pd.tnic>
Date:   Fri, 21 Apr 2017 19:26:03 +0200
From:   Borislav Petkov <bp@...en8.de>
To:     "Baicar, Tyler" <tbaicar@...eaurora.org>
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Subject: Re: [PATCH V15 03/11] cper: add timestamp print to CPER status
 printing

On Fri, Apr 21, 2017 at 10:04:35AM -0600, Baicar, Tyler wrote:
> This is basically what I already had in v14...you asked to move it into a
> different if-statement? https://lkml.org/lkml/2017/4/12/397

Well, clearly I've been smoking some nasty potent sh*t. :-\

/me goes and looks at the spec:

"Bit 0 – Timestamp is precise if this bit is set and correlates to the
time of the error event."

So why are we even printing the timestamp when !precise?

IOW, I think we should do:

	if (!(timestamp[3] & 0x1))
		printk("%stimestamp imprecise\n", pfx);
	else {
		sec = ..
		min = ...

		...
	}

and print the actual values only when the timestamp is precise.
Otherwise it has *some* values which could just as well be completely
random. And it's not like we're reporting the error tomorrow - it is
mostly a couple of seconds from logging to the fw pushing it out...

-- 
Regards/Gruss,
    Boris.

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