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Date: Mon, 28 Dec 2015 10:13:13 +0200
From: Konstantin Belousov <kostikbel@gmail.com>
To: Bruce Evans <brde@optusnet.com.au>
Cc: Ian Lepore <ian@freebsd.org>, Dmitry Chagin <dchagin@freebsd.org>,
 src-committers@freebsd.org, svn-src-all@freebsd.org,
 svn-src-head@freebsd.org
Subject: Re: svn commit: r292777 - in head: lib/libc/sys sys/kern
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On Mon, Dec 28, 2015 at 09:35:11AM +1100, Bruce Evans wrote:
> If this causes a panic, then it is from a sanity check detecting the
> invalid conversion later.  A negative value in days breaks the loop
> logic but seems to give premature exit from the loops instead of many
> iterations.
It causes the panic due to out of bound accesses to bin2bcd_data[] array.
The issue affects around twenty rtc drivers, according to the quick grep
for clock_ts_to_ct() usage.  It probably also affects geom raid modules,
but I did not looked there at all.

As I understand, people prefer to have ability to test practically
useless values for the current time, by the cost the unplugged easy
kernel panic, in the production systems ? Am I right ? The commit gave
the immediate relief for the issue. If somebody have the correct fix
for clock_ts_to_ct(), I am happy to see this commit reverted after the
proper fix.