From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oa0-f48.google.com (mail-oa0-f48.google.com [209.85.219.48]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id BBE292C00A4 for ; Sat, 15 Feb 2014 07:42:28 +1100 (EST) Received: by mail-oa0-f48.google.com with SMTP id l6so14967474oag.7 for ; Fri, 14 Feb 2014 12:42:25 -0800 (PST) MIME-Version: 1.0 Date: Fri, 14 Feb 2014 14:42:24 -0600 Message-ID: Subject: Anyone using SysRQ key sequences on console serial port ? From: John Donnelly To: linuxppc-dev@lists.ozlabs.org Content-Type: multipart/alternative; boundary=089e015366b4e4a36b04f263d7a0 List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , --089e015366b4e4a36b04f263d7a0 Content-Type: text/plain; charset=ISO-8859-1 Hi, I tried using the SysRq hotkey sequence on a serial console - 3.11.0-5-powerpc-e500mc system, by issuing a " break " and the system immediately wedges after displaying "SysRQ : HELP : " using both "Putty" and "Teraterm" terminal emulators. I know the system is dead because my ssh sessions stopped too. http://en.wikipedia.org/wiki/Magic_SysRq_key . -- *Regards,* * John.* *--* *o* Energy-efficiency is #1 reason data centers look to expand. -- Digital Realty Trust *o* Green Data Centers spending to increase 300% worldwide by 2016. -- Pike Research *o *Data Centers have become as vital to the functioni ng of society as power stations. -- The Economist --089e015366b4e4a36b04f263d7a0 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable
Hi,

=A0I tried using the SysRq hotkey sequenc= e on a serial console - 3.11.0-5-powerpc-e500mc system, by issuing a "= break " and the system immediately wedges after displaying "SysR= Q : HELP : " using both "Putty" and "Teraterm" =A0= terminal emulators. I know the system is dead because my ssh sessions stopp= ed too.=A0



=A0=A0

--

Regards,
=A0John.

--

o= =A0= Energy-efficiency is #1 reason data centers look to expand. =A0-- Digital R= ealty Trust
o=A0Green Data Centers= spending to increase 300% worldwide by 2016. =A0-- Pike Research
o=A0Data Centers have=A0become as vital to the=A0functioni ng=A0of society as p= ower stations. =A0-- The Economist

--089e015366b4e4a36b04f263d7a0-- From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wi0-x22f.google.com (mail-wi0-x22f.google.com [IPv6:2a00:1450:400c:c05::22f]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 55F5C2C009F for ; Mon, 17 Feb 2014 02:57:01 +1100 (EST) Received: by mail-wi0-f175.google.com with SMTP id hm4so1694880wib.14 for ; Sun, 16 Feb 2014 07:56:55 -0800 (PST) MIME-Version: 1.0 Sender: paul.gortmaker@gmail.com In-Reply-To: References: From: Paul Gortmaker Date: Sun, 16 Feb 2014 10:56:24 -0500 Message-ID: Subject: Re: Anyone using SysRQ key sequences on console serial port ? To: John Donnelly Content-Type: text/plain; charset=ISO-8859-1 Cc: linuxppc-dev@lists.ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Fri, Feb 14, 2014 at 3:42 PM, John Donnelly wrote: > Hi, > > I tried using the SysRq hotkey sequence on a serial console - > 3.11.0-5-powerpc-e500mc system, by issuing a " break " and the system > immediately wedges after displaying "SysRQ : HELP : " using both "Putty" and > "Teraterm" terminal emulators. I know the system is dead because my ssh > sessions stopped too. Yes it does work -- or at least it _did_ work. Make sure your dts has an entry compatible = "fsl,ns16550", "ns16550"; since that enables a workaround I'd added for a hardware errata relating to sending breaks over the serial console. What you describe above makes me think you aren't getting the workaround enabled. Paul. -- > > http://en.wikipedia.org/wiki/Magic_SysRq_key . > > > > > -- > > Regards, > John. > > -- > > o Energy-efficiency is #1 reason data centers look to expand. -- Digital > Realty Trust > o Green Data Centers spending to increase 300% worldwide by 2016. -- Pike > Research > o Data Centers have become as vital to the functioni > ng of society as power stations. -- The Economist > > > _______________________________________________ > Linuxppc-dev mailing list > Linuxppc-dev@lists.ozlabs.org > https://lists.ozlabs.org/listinfo/linuxppc-dev From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from na01-by2-obe.outbound.protection.outlook.com (mail-by2lp0236.outbound.protection.outlook.com [207.46.163.236]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id C22572C00D0 for ; Tue, 18 Feb 2014 06:37:14 +1100 (EST) Message-ID: <1392665821.6733.630.camel@snotra.buserror.net> Subject: Re: Anyone using SysRQ key sequences on console serial port ? From: Scott Wood To: Paul Gortmaker Date: Mon, 17 Feb 2014 13:37:01 -0600 In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" MIME-Version: 1.0 Cc: John Donnelly , linuxppc-dev@lists.ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Sun, 2014-02-16 at 10:56 -0500, Paul Gortmaker wrote: > On Fri, Feb 14, 2014 at 3:42 PM, John Donnelly wrote: > > Hi, > > > > I tried using the SysRq hotkey sequence on a serial console - > > 3.11.0-5-powerpc-e500mc system, by issuing a " break " and the system > > immediately wedges after displaying "SysRQ : HELP : " using both "Putty" and > > "Teraterm" terminal emulators. I know the system is dead because my ssh > > sessions stopped too. > > Yes it does work -- or at least it _did_ work. Make sure your dts has an entry > > compatible = "fsl,ns16550", "ns16550"; > > since that enables a workaround I'd added for a hardware errata relating > to sending breaks over the serial console. What you describe above > makes me think you aren't getting the workaround enabled. Also make sure CONFIG_SERIAL_8250_FSL is enabled. -Scott From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oa0-f47.google.com (mail-oa0-f47.google.com [209.85.219.47]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id E20F62C00BE for ; Wed, 19 Feb 2014 06:47:57 +1100 (EST) Received: by mail-oa0-f47.google.com with SMTP id m1so19686830oag.20 for ; Tue, 18 Feb 2014 11:47:54 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <1392665821.6733.630.camel@snotra.buserror.net> References: <1392665821.6733.630.camel@snotra.buserror.net> Date: Tue, 18 Feb 2014 13:47:54 -0600 Message-ID: Subject: Re: Anyone using SysRQ key sequences on console serial port ? From: John Donnelly To: Scott Wood Content-Type: multipart/alternative; boundary=001a11c2ec9a54869b04f2b38c16 Cc: Paul Gortmaker , linuxppc-dev@lists.ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , --001a11c2ec9a54869b04f2b38c16 Content-Type: text/plain; charset=ISO-8859-1 I am enable to get one keyboard sequence responded to with the noted change in the dts . for instance: SysRQ ( Break) c Panics .. Which is a good response, and since it doesn't require a return to user mode ( I suspect ) it appears to work. Any other requests fail to report any information : SysRQ (break ) l - list active processes m - list memory Any additional SysRQ are ignored., and the system appears hung. On an reference Intel platform, multiple SyqRQ can be issued and the system remains healthy . On Mon, Feb 17, 2014 at 1:37 PM, Scott Wood wrote: > On Sun, 2014-02-16 at 10:56 -0500, Paul Gortmaker wrote: > > On Fri, Feb 14, 2014 at 3:42 PM, John Donnelly > wrote: > > > Hi, > > > > > > I tried using the SysRq hotkey sequence on a serial console - > > > 3.11.0-5-powerpc-e500mc system, by issuing a " break " and the system > > > immediately wedges after displaying "SysRQ : HELP : " using both > "Putty" and > > > "Teraterm" terminal emulators. I know the system is dead because my > ssh > > > sessions stopped too. > > > > Yes it does work -- or at least it _did_ work. Make sure your dts has > an entry > > > > compatible = "fsl,ns16550", "ns16550"; > > > > since that enables a workaround I'd added for a hardware errata relating > > to sending breaks over the serial console. What you describe above > > makes me think you aren't getting the workaround enabled. > > Also make sure CONFIG_SERIAL_8250_FSL is enabled. > > -Scott > > > -- *Regards,* * John.* *--* *o* Energy-efficiency is #1 reason data centers look to expand. -- Digital Realty Trust *o* Green Data Centers spending to increase 300% worldwide by 2016. -- Pike Research *o *Data Centers have become as vital to the functioni ng of society as power stations. -- The Economist --001a11c2ec9a54869b04f2b38c16 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable
I am enable to get one keyboard sequence responded to with= the noted change in the dts .

=A0for instance:=A0
=

=A0 =A0SysRQ ( Break) =A0 c=A0

=A0 Panics .. Which is a good response, and since it doesn't requ= ire a return to user mode ( I suspect ) =A0it appears to work.=A0

Any other requests fail to report any information :=A0<= /div>

=A0SysRQ (break ) =A0l - list active processes
=A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0m - list memory= =A0

=A0 Any additional SysRQ are ignored., and the= system appears hung.

=A0On an reference Intel platform, multiple SyqRQ can b= e issued and the system remains healthy .



=A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0
=A0

=A0 =A0 =A0 =A0 =A0=A0


On Mon, Feb 17, 2014 at 1:37 PM, Scot= t Wood <scottwood@freescale.com> wrote:
On Sun, 2014-02-16 at 10:56 -0500, Paul Gort= maker wrote:
> On Fri, Feb 14, 2014 at 3:42 PM, John Donnelly <john.d@servergy.com> wrote:
> > Hi,
> >
> > =A0I tried using the SysRq hotkey sequence on a serial console -<= br> > > 3.11.0-5-powerpc-e500mc system, by issuing a " break " = and the system
> > immediately wedges after displaying "SysRQ : HELP : " u= sing both "Putty" and
> > "Teraterm" =A0terminal emulators. I know the system is = dead because my ssh
> > sessions stopped too.
>
> Yes it does work -- or at least it _did_ work. =A0Make sure your dts h= as an entry
>
> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 compatible =3D "f= sl,ns16550", "ns16550";
>
> since that enables a workaround I'd added for a hardware errata re= lating
> to sending breaks over the serial console. =A0 What you describe above=
> makes me think you aren't getting the workaround enabled.

Also make sure CONFIG_SERIAL_8250_FSL is enabled.

-Scott





--

Regards,
=A0John.

--

o= =A0= Energy-efficiency is #1 reason data centers look to expand. =A0-- Digital R= ealty Trust
o=A0Green Data Centers= spending to increase 300% worldwide by 2016. =A0-- Pike Research
o=A0Data Centers have=A0become as vital to the=A0functioni ng=A0of society as p= ower stations. =A0-- The Economist

--001a11c2ec9a54869b04f2b38c16-- From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.windriver.com (mail.windriver.com [147.11.1.11]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id C8B432C00C4 for ; Thu, 20 Feb 2014 05:41:50 +1100 (EST) Message-ID: <5304FB19.4050208@windriver.com> Date: Wed, 19 Feb 2014 13:42:33 -0500 From: Paul Gortmaker MIME-Version: 1.0 To: John Donnelly , Scott Wood Subject: Re: Anyone using SysRQ key sequences on console serial port ? References: <1392665821.6733.630.camel@snotra.buserror.net> In-Reply-To: Content-Type: text/plain; charset="ISO-8859-1" Cc: linuxppc-dev@lists.ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , [BTW, your html mail may be ignored by most people ; for example most of the linux lists on vger.kernel.org actively reject it; top posting isn't going to help either... ] On 14-02-18 02:47 PM, John Donnelly wrote: > I am enable to get one keyboard sequence responded to with the noted change > in the dts . > > for instance: > > SysRQ ( Break) c > > Panics .. Which is a good response, and since it doesn't require a return > to user mode ( I suspect ) it appears to work. > > Any other requests fail to report any information : > > SysRQ (break ) l - list active processes > m - list memory > > Any additional SysRQ are ignored., and the system appears hung. It must be something specific about your particular platform, or the custom patches you have applied then. I just tested today's linux-next tree (i.e. the latest bleeding edge stuff) and it still works for the sbc8548 (defconfig + enable magic SYSRQ option). I did "s" (sync) multiple times and "?" then "m" for memory dump (obviously those chars don't get echo'd to the console.... --------------------------------------- root@sbc8548:~# cat /proc/cpuinfo |grep cpu cpu : e500v2 root@sbc8548:~# SysRq : Emergency Sync Emergency Sync complete SysRq : Emergency Sync Emergency Sync complete SysRq : HELP : loglevel(0-9) reboot(b) crash(c) terminate-all-tasks(e) memory-full-oom-kill(f) kill-all-tasks(i) thaw-filesystems(j) show-memory-usage(m) nice-all-RT-tasks(n) poweroff(o) show-registers(p) show-all-timers(q) sync(s) show-task-states(t) unmount(u) show-blocked-tasks(w) SysRq : Show Memory Mem-Info: DMA per-cpu: CPU 0: hi: 186, btch: 31 usd: 132 active_anon:738 inactive_anon:29 isolated_anon:0 active_file:915 inactive_file:2219 isolated_file:0 unevictable:0 dirty:0 writeback:0 unstable:0 free:188325 slab_reclaimable:488 slab_unreclaimable:778 mapped:1006 shmem:44 pagetables:83 bounce:0 free_cma:0 DMA free:753300kB min:3520kB low:4400kB high:5280kB active_anon:2952kB inactive_anon:116kB active_file:3660kB inactive_file:8876kB unevictable:0kB isolated(anon):0kB isolated(file):0kB present:786432kB managed:775916kB mlocked:0kB dirty:0kB writeback:0kB mapped:4024kB shmem:176kB slab_reclaimable:1952kB slab_unreclaimable:3112kB kernel_stack:264kB pagetables:332kB uns table:0kB bounce:0kB free_cma:0kB writeback_tmp:0kB pages_scanned:0 all_unreclaimable? no lowmem_reserve[]: 0 0 0 DMA: 403*4kB (UEM) 271*8kB (UEM) 131*16kB (UM) 35*32kB (UM) 15*64kB (UEM) 1*128kB (M) 1*256kB (M) 1*512kB (U) 1*1024kB (U) 3*2048kB (UEM) 180*4096kB (MR) = 753300kB 3178 total pagecache pages 0 pages in swap cache Swap cache stats: add 0, delete 0, find 0/0 Free swap = 0kB Total swap = 0kB 196608 pages RAM 0 pages HighMem/MovableOnly 2629 pages reserved --------------------------------------- Paul. -- > > On an reference Intel platform, multiple SyqRQ can be issued and the > system remains healthy . > > > > > > > > > > On Mon, Feb 17, 2014 at 1:37 PM, Scott Wood wrote: > >> On Sun, 2014-02-16 at 10:56 -0500, Paul Gortmaker wrote: >>> On Fri, Feb 14, 2014 at 3:42 PM, John Donnelly >> wrote: >>>> Hi, >>>> >>>> I tried using the SysRq hotkey sequence on a serial console - >>>> 3.11.0-5-powerpc-e500mc system, by issuing a " break " and the system >>>> immediately wedges after displaying "SysRQ : HELP : " using both >> "Putty" and >>>> "Teraterm" terminal emulators. I know the system is dead because my >> ssh >>>> sessions stopped too. >>> >>> Yes it does work -- or at least it _did_ work. Make sure your dts has >> an entry >>> >>> compatible = "fsl,ns16550", "ns16550"; >>> >>> since that enables a workaround I'd added for a hardware errata relating >>> to sending breaks over the serial console. What you describe above >>> makes me think you aren't getting the workaround enabled. >> >> Also make sure CONFIG_SERIAL_8250_FSL is enabled. >> >> -Scott >> >> >> > >