linux-kernel - Re: 答复: 答复: 答复: [PATCH] kdb: Fix the deadlock issue in KDB debugging.

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20240312102419.GC202685@aspen.lan>
Date: Tue, 12 Mar 2024 10:24:19 +0000
From: Daniel Thompson <daniel.thompson@...aro.org>
To: Liuye <liu.yeC@....com>
Cc: "jason.wessel@...driver.com" <jason.wessel@...driver.com>,
	"dianders@...omium.org" <dianders@...omium.org>,
	"gregkh@...uxfoundation.org" <gregkh@...uxfoundation.org>,
	"jirislaby@...nel.org" <jirislaby@...nel.org>,
	"kgdb-bugreport@...ts.sourceforge.net" <kgdb-bugreport@...ts.sourceforge.net>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"linux-serial@...r.kernel.org" <linux-serial@...r.kernel.org>
Subject: Re: 答复: 答复: 答复:
 [PATCH] kdb: Fix the deadlock issue in KDB debugging.

On Tue, Mar 12, 2024 at 10:04:54AM +0000, Liuye wrote:
> >On Tue, Mar 12, 2024 at 08:37:11AM +0000, Liuye wrote:
> >> I know that you said schedule_work is not NMI save, which is the first
> >> issue. Perhaps it can be fixed using irq_work_queue. But even if
> >> irq_work_queue is used to implement it, there will still be a deadlock
> >> problem because slave cpu1 still has not released the running queue
> >> lock of master CPU0.
> >
> >This doesn't sound right to me. Why do you think CPU1 won't release
> >the run queue lock?
>
> In this example, CPU1 is waiting for CPU0 to release dbg_slave_lock.

That shouldn't be a problem. CPU0 will have released that lock by
the time the irq work is dispatched.


Daniel.