Re: /proc/kmsg giving eof on blocking read

From: Kay Sievers
Date: Thu Nov 22 2012 - 16:26:04 EST


On Thu, Nov 22, 2012 at 11:44 AM, Jan Schmidt <list.lkml@xxxxxxxxxxxxx> wrote:
> I'm currently debugging something in btrfs in good old printk style, generating
> around 10MB/min. I'm seeing /proc/kmsg returning eof on a blocking read (and,
> side note, syslog-ng won't reopen it, effectively stopping logging kernel
> messages silently).

Are you sure there is not something else that opens the same file?
Even once might be enough to return 0. The too simple locking logic in
/proc/kmsg cannot support multiple readers properly, it never did.

Kay
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