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Date:   Mon, 26 Sep 2022 10:24:41 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Dave Hansen <dave.hansen@intel.com>
Cc:     Alexei Starovoitov <alexei.starovoitov@gmail.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        tech-board@lists.linuxfoundation.org,
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        Kernel Team <Kernel-team@fb.com>,
        Borislav Petkov <bp@alien8.de>, brijesh.singh@amd.com,
        Dan Williams <dan.j.williams@intel.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        "H. Peter Anvin" <hpa@zytor.com>, jane.chu@oracle.com,
        "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        LKML <linux-kernel@vger.kernel.org>,
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        Ingo Molnar <mingo@redhat.com>, seanjc@google.com,
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        Thomas Gleixner <tglx@linutronix.de>,
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        John Fastabend <john.fastabend@gmail.com>,
        "open list:BPF (Safe dynamic programs and tools)" 
        <bpf@vger.kernel.org>
Subject: Re: [syzbot] WARNING in __change_page_attr_set_clr
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On Sun, Sep 25, 2022 at 05:10:19PM -0700, Dave Hansen wrote:

> Peter, I remember an earlier version of your patch having some various
> enforcement modes.  Since the strict enforcement has actually broken a
> few things, should we resurrect the nicer soft detection mode?  Or,
> maybe make the soft one the only mode for now?

Well, I think we'll have to disable the whole thing for i386, but I'm
sincerely hoping this is the only one we'll hit on x86_64 -- I did spend
some effort fixing W^X issues a while back.