From: Jiri Slaby <jirislaby@kernel.org>
To: liu.yec@h3c.com, daniel.thompson@linaro.org
Cc: dianders@chromium.org, gregkh@linuxfoundation.org,
jason.wessel@windriver.com, kgdb-bugreport@lists.sourceforge.net,
linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org
Subject: Re: [PATCH V4] kdb: Fix the deadlock issue in KDB debugging.
Date: Fri, 22 Mar 2024 07:54:42 +0100 [thread overview]
Message-ID: <d3b77177-7c00-4459-9515-37afe741e9dd@kernel.org> (raw)
In-Reply-To: <20240321115017.2879691-1-liu.yec@h3c.com>
On 21. 03. 24, 12:50, liu.yec@h3c.com wrote:
> From: LiuYe <liu.yeC@h3c.com>
>
> Currently, if CONFIG_KDB_KEYBOARD is enabled, then kgdboc will
> attempt to use schedule_work() to provoke a keyboard reset when
> transitioning out of the debugger and back to normal operation.
> This can cause deadlock because schedule_work() is not NMI-safe.
>
> The stack trace below shows an example of the problem. In this
> case the master cpu is not running from NMI but it has parked
> the slave CPUs using an NMI and the parked CPUs is holding
> spinlocks needed by schedule_work().
I am missing here an explanation (perhaps because I cannot find any docs
for irq_work) why irq_work works in this case.
And why you need to schedule another work in the irq_work and not do the
job directly.
thanks,
--
js
suse labs
next prev parent reply other threads:[~2024-03-22 6:54 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-02-28 2:56 [PATCH] kdb: Fix the deadlock issue in KDB debugging LiuYe
2024-02-28 12:05 ` Daniel Thompson
2024-03-01 3:30 ` 答复: " Liuye
2024-03-01 10:59 ` Daniel Thompson
2024-03-12 8:37 ` 答复: " Liuye
2024-03-12 9:57 ` Daniel Thompson
2024-03-12 10:04 ` 答复: " Liuye
2024-03-12 10:24 ` Daniel Thompson
2024-03-13 1:22 ` 答复: " Liuye
2024-03-13 14:17 ` Daniel Thompson
2024-03-14 7:06 ` 答复: " Liuye
2024-03-14 13:09 ` Daniel Thompson
2024-03-15 9:59 ` 答复: " Liuye
2024-03-16 2:34 ` [PATCH v1] " liu.yec
2024-03-20 16:28 ` Daniel Thompson
2024-03-21 2:26 ` [PATCH V3] " liu.yec
2024-03-21 7:38 ` Greg KH
2024-03-21 7:57 ` 答复: " Liuye
2024-03-21 11:04 ` Daniel Thompson
2024-03-21 11:50 ` [PATCH V4] " liu.yec
2024-03-22 6:54 ` Jiri Slaby [this message]
2024-03-22 7:50 ` 答复: " Liuye
2024-03-22 15:58 ` Daniel Thompson
2024-03-23 1:41 ` [PATCH V5] " liu.yec
2024-03-25 16:54 ` Daniel Thompson
2024-03-26 0:47 ` 答复: " Liuye
2024-03-26 7:40 ` [PATCH V6] " liu.yec
2024-03-26 8:22 ` Greg KH
2024-03-26 8:54 ` [PATCH V7] " liu.yec
2024-04-02 12:58 ` Daniel Thompson
2024-04-03 6:11 ` [PATCH V8] " liu.yec
2024-04-03 13:58 ` Daniel Thompson
2024-04-03 22:22 ` Andy Shevchenko
2024-04-08 1:44 ` LiuYe
2024-04-08 10:29 ` Andy Shevchenko
2024-04-09 2:03 ` [PATCH V9] " liu.yec
2024-04-10 2:06 ` [PATCH V10] " liu.yec
2024-04-10 3:59 ` Andy Shevchenko
2024-04-10 5:30 ` Greg KH
2024-04-10 5:54 ` 答复: " Liuye
2024-04-10 5:59 ` Greg KH
2024-04-10 6:10 ` 答复: " Liuye
2024-04-10 6:15 ` Greg KH
2024-04-10 6:30 ` 答复: " Liuye
2024-04-10 7:18 ` [PATCH V11] " liu.yec
2024-04-10 8:24 ` 答复: 答复: 答复: [PATCH V10] " Greg KH
2024-04-10 8:38 ` 答复: " Liuye
2024-03-02 20:44 ` [PATCH] " Greg KH
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