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From: Steven Rostedt <rostedt@goodmis.org>
To: Dmitry Vyukov <dvyukov@google.com>
Cc: syzkaller <syzkaller@googlegroups.com>,
	syzbot <syzbot+61e04e51b7ac86930589@syzkaller.appspotmail.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Jens Axboe <axboe@kernel.dk>, Borislav Petkov <bp@alien8.de>,
	"H. Peter Anvin" <hpa@zytor.com>,
	Jim Mattson <jmattson@google.com>, Joerg Roedel <joro@8bytes.org>,
	KVM list <kvm@vger.kernel.org>,
	linux-block <linux-block@vger.kernel.org>,
	LKML <linux-kernel@vger.kernel.org>,
	Mark Rutland <mark.rutland@arm.com>,
	masahiroy@kernel.org, Ingo Molnar <mingo@redhat.com>,
	Paolo Bonzini <pbonzini@redhat.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Sean Christopherson <seanjc@google.com>,
	syzkaller-bugs <syzkaller-bugs@googlegroups.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Vitaly Kuznetsov <vkuznets@redhat.com>,
	Wanpeng Li <wanpengli@tencent.com>, Will Deacon <will@kernel.org>,
	"the arch/x86 maintainers" <x86@kernel.org>
Subject: Re: [syzbot] possible deadlock in del_gendisk
Date: Tue, 13 Apr 2021 14:43:35 -0400
Message-ID: <20210413144335.4ff14cf2@gandalf.local.home> (raw)
In-Reply-To: <20210413144009.6ed2feb8@gandalf.local.home>

On Tue, 13 Apr 2021 14:40:09 -0400
Steven Rostedt <rostedt@goodmis.org> wrote:

> ------------[ cut here ]------------
> raw_local_irq_restore() called with IRQs enabled
> WARNING: CPU: 0 PID: 8777 at kernel/locking/irqflag-debug.c:9 warn_bogus_irq_restore kernel/locking/irqflag-debug.c:9 [inline]
> WARNING: CPU: 0 PID: 8777 at kernel/locking/irqflag-debug.c:9 warn_bogus_irq_restore+0x1d/0x20 kernel/locking/irqflag-debug.c:7

In fact, when you have the above, which is a WARN() with text:

 "raw_local_irq_restore() called with IRQs enabled"

It is pretty much guaranteed that all triggers of this bug will have the
above warning with the same text.

-- Steve

  reply index

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-04-13 17:33 syzbot
2021-04-13 17:41 ` Steven Rostedt
2021-04-13 17:43   ` Steven Rostedt
2021-04-13 18:24     ` Dmitry Vyukov
2021-04-13 18:40       ` Steven Rostedt
2021-04-13 18:43         ` Steven Rostedt [this message]
2021-04-16  7:51           ` Bisections with different bug manifestations Dmitry Vyukov
2021-04-16 13:13             ` Steven Rostedt
2021-04-16 13:26               ` Dmitry Vyukov
2021-04-16 13:48                 ` Dmitry Vyukov

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