Re: [PATCH 3/3] EDAC: Convert AMD EDAC pieces to use RAS printk buffer

[Borislav Petkov <bp@amd64.org>]

On Mon, Mar 12, 2012 at 04:18:57PM +0000, Luck, Tony wrote:
> > This is an initial version of the patch which converts MCE decoding
> > facilities to use the RAS printk buffer. When there's no userspace agent
> > running (i.e., /sys/devices/system/ras/agent == 0), we fall back to the
> > default printk'ing into dmesg which is what we've been doing so far.
> 
> This looks unpleasant if your userspace agent set this sysfs file, and
> then dies (or gets killed).

Yeah, having a sysfs file like that felt unpleasant - I was hoping
someone would point me to a better solution...

> Perhaps you need some device file that the agent keeps open (so if the
> agent goes away, the kernel gets a "close" on the device to tell it
> to revert). But even with this sort of solution you would still have
> to worry about races.

Sounds better, especially the close-on-exit part. Please elaborate on
the races...

Thanks.

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Boris.

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