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From: Vince Weaver <vincent.weaver@maine.edu>
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Date: Fri, 4 May 2018 10:35:53 -0400 (EDT)
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To: Josh Poimboeuf <jpoimboe@redhat.com>
cc: Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@kernel.org>,
        linux-kernel@vger.kernel.org,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Andy Lutomirski <luto@kernel.org>
Subject: Re: perf: fuzzer causes stack going in wrong direction warnings
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On Wed, 2 May 2018, Josh Poimboeuf wrote:

> After looking closer, I realized that at least some of these warnings
> are due to bad unwind hints in the entry code.  Can you try this patch
> instead of the last one?

with just this new patch applied I still get warnings such as this:

[  469.436218] WARNING: can't dereference registers at 00000000886d9235 for ip apic_timer_interrupt+0xa/0x20
[  790.499655] WARNING: stack recursion on stack type 2
[  790.907092] WARNING: stack going in the wrong direction? ip=native_sched_clock+0x9/0x90
[ 3632.876656] WARNING: can't dereference iret registers at 000000001754e5aa for ip nmi_restore+0x16/0x2b
[ 3650.161250] WARNING: missing regs for base reg R10 at ip native_sched_clock+0xd/0x90


Vince