From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Chiang Date: Thu, 14 Jan 2010 05:01:42 +0000 Subject: Re: lockdep support caused an MCA Message-Id: <20100114050142.GE27766@ldl.fc.hp.com> List-Id: References: <20100111195825.GE10162@ldl.fc.hp.com> In-Reply-To: <20100111195825.GE10162@ldl.fc.hp.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable To: linux-ia64@vger.kernel.org * Luming Yu : > On Tue, Jan 12, 2010 at 9:51 AM, Yu, Luming wrote: > > Let me check if I can get access to an HP rx8640 to re-spin the patch. > > > > > > -----Original Message----- > > From: Alex Chiang [mailto:achiang@hp.com] > > Sent: Tuesday, January 12, 2010 3:58 AM > > To: Yu, Luming; Luck, Tony > > Cc: linux-ia64@vger.kernel.org > > Subject: lockdep support caused an MCA > > > > This patch 2f02b4a12b24c9f077c6d739ac23c9b90840ccca: > > > > Author: Luming Yu =A02009-12-04 09:14:30 > > > > =A0 =A0[IA64] lockdep support > > > > =A0 =A0Basic functionality for lockdep on ia64. > > > > =A0 =A0Known issues: > > =A0 =A00. dynamic allocate per CPU area in lockdep. > > =A0 =A01. lock held in leave kernel. > > =A0 =A02. enabling CONFIG_DEBUG_LOCKDEP triggers the lockdep warning. > > =A0 =A03. Need to implement save_stack functions > > =A0 =A04. Replace some cpp macros with inline functions > > =A0 =A05. Add nmi_enter/nmi_exit > > > > =A0 =A0Signed-off-by: Bob Picco > > =A0 =A0Signed-off-by: Yu Luming > > =A0 =A0Signed-off-by: Tony Luck > > > > causes a very early MCA on an HP rx8640. > > > > Unfortunately, even with early_printk turned on, the machine > > encounters the MCA and reboots before any output occurs, so I > > don't have any further information. > > > > I haven't done any other triage on this as the patch has already > > been dropped from Tony's tree, but I'd be happy to test the next > > go-around. >=20 > I have managed to get the patch run on a HP rx8640 system with > latest next tree + ia64-lockdep patch. The following is the part of > boot log with lockdep footprints..The interesting thing is > lockdep code seems to have detected possible recursive locking > with the kernel on the platform. How many cells was your system? Mine was 2 cells (for a total of 16 CPUs). I just mention this because booting on a 1 cell config is quite different from a multi-cell config. Thanks for getting it going though. /ac