From: Michael Ellerman <mpe@ellerman.id.au>
To: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>,
linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org
Cc: benh@kernel.crashing.org, paulus@samba.org, npiggin@gmail.com,
gpiccoli@linux.vnet.ibm.com,
Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
Subject: Re: [PATCH] powerpc/xmon: Fix an unexpected xmon onoff state change
Date: Thu, 16 Feb 2017 16:09:18 +1100 [thread overview]
Message-ID: <87shnek9hd.fsf@concordia.ellerman.id.au> (raw)
In-Reply-To: <1487144990-5969-1-git-send-email-xinhui.pan@linux.vnet.ibm.com>
Pan Xinhui <xinhui.pan@linux.vnet.ibm.com> writes:
> Once xmon is triggered by sysrq-x, it is enabled always afterwards even
> if it is disabled during boot. This will cause a system reset interrut
> fail to dump. So keep xmon in its original state after exit.
>
> Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
> ---
> arch/powerpc/xmon/xmon.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c
> index 9c0e17c..721212f 100644
> --- a/arch/powerpc/xmon/xmon.c
> +++ b/arch/powerpc/xmon/xmon.c
> @@ -76,6 +76,7 @@ static int xmon_gate;
> #endif /* CONFIG_SMP */
>
> static unsigned long in_xmon __read_mostly = 0;
> +static int xmon_off = 0;
>
> static unsigned long adrs;
> static int size = 1;
> @@ -3250,6 +3251,8 @@ static void sysrq_handle_xmon(int key)
> /* ensure xmon is enabled */
> xmon_init(1);
> debugger(get_irq_regs());
> + if (xmon_off)
> + xmon_init(0);
> }
I don't think this is right.
xmon_off is only true if you boot with xmon=off on the command line.
So if you boot with CONFIG_XMON_DEFAULT=n, and nothing on the command
line, then enter xmon via sysrq, then exit, xmon will still be enabled.
cheers
next prev parent reply other threads:[~2017-02-16 5:09 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-02-15 7:49 [PATCH] powerpc/xmon: Fix an unexpected xmon onoff state change Pan Xinhui
2017-02-15 21:22 ` Guilherme G. Piccoli
2017-02-16 5:09 ` Michael Ellerman [this message]
2017-02-16 10:57 ` Guilherme G. Piccoli
2017-02-16 11:51 ` Pan Xinhui
2017-02-17 6:05 ` Michael Ellerman
2017-02-17 9:30 ` Pan Xinhui
2017-02-17 12:25 ` Guilherme G. Piccoli
2017-02-20 4:46 ` Michael Ellerman
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