ipmi patch for review

From: Gleb Smirnoff <glebius_at_FreeBSD.org>
Date: Tue, 17 Sep 2013 14:21:10 +0400
  Hi!

  When system is writing a kernel core dump, it issues watchdog
pat wdog_kern_pat(WD_LASTVAL). If ipmi is in action, it registers
ipmi_wd_event() as event for watchdog. Thus ipmi_wd_event() is
called in dumping context.

The problem is that ipmi_wd_event() calls into ipmi_set_watchdog(),
that calls into ipmi_alloc_request(), which uses M_WAITOK and
thus sleeps. This is a smaller problem, since can be converted to
M_NOWAIT. But ipmi_set_watchdog() then calls into
ipmi_submit_driver_request(), which calls msleep() any time.

  The attached patch allows me to successfully write cores in
presence of IPMI.

-- 
Totus tuus, Glebius.

Received on Tue Sep 17 2013 - 08:21:20 UTC

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