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Date:   Thu, 6 Aug 2020 21:23:33 +0200
From:   Joerg Roedel <jroedel@suse.de>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Ingo Molnar <mingo@kernel.org>,
        "Jason A. Donenfeld" <Jason@zx2c4.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Borislav Petkov <bp@alien8.de>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [GIT PULL] x86/mm changes for v5.9
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On Thu, Aug 06, 2020 at 12:02:40PM -0700, Linus Torvalds wrote:
> But you may obviously have different settings for CONFIG_X86_5LEVEL,
> and maybe that ends up changing something?
> 
> But since apparently it's not immediately obvious what the problem is,
> I'll revert it for now.

Yes, that's the best for now. My gut feeling is that the fault Jason is
seeing didn't happen on a vmalloc address, but I can't prove that yet.

And if this is true it means that more work is needed before the syncing
on x86-64 can be removed, so reverting is the best for now.

Jason, can you share more details about the test setup which triggers
this? Like the .config and the machine setup, ideally a qemu
command-line, and how to reproduce it on that setup.

Thanks,

	Joerg