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From:   Jian-Hong Pan <jian-hong@endlessm.com>
Date:   Mon, 16 Mar 2020 17:17:56 +0800
Message-ID: <CAPpJ_eetjhmPwXXXn2y-vibRCK6rrKsFZgC+YGzxO4fMrCKpuQ@mail.gmail.com>
Subject: Re: [PATCH] Revert "x86/reboot, efi: Use EFI reboot for Acer
 TravelMate X514-51T"
To:     Borislav Petkov <bp@alien8.de>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        "H . Peter Anvin" <hpa@zytor.com>,
        Ard Biesheuvel <ardb@kernel.org>,
        Kees Cook <keescook@chromium.org>,
        Anton Vorontsov <anton@enomsg.org>,
        Colin Cross <ccross@android.com>,
        Tony Luck <tony.luck@intel.com>, x86@kernel.org,
        Linux Kernel <linux-kernel@vger.kernel.org>,
        linux-efi@vger.kernel.org,
        Linux Upstreaming Team <linux@endlessm.com>
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Borislav Petkov <bp@alien8.de> =E6=96=BC 2020=E5=B9=B43=E6=9C=8812=E6=97=A5=
 =E9=80=B1=E5=9B=9B =E4=B8=8B=E5=8D=886:46=E5=AF=AB=E9=81=93=EF=BC=9A
>
> On Thu, Mar 12, 2020 at 04:33:42PM +0800, Jian-Hong Pan wrote:
> > This reverts commit 0082517fa4bce073e7cf542633439f26538a14cc.
> >
> > According to Acer's information, this reboot issue is fixed since 1.08
> > and newer BIOS. So, we can revert the quirk.
>
> We can?
>
> How do you know *everyone* affected will update their BIOS?
>
> And what's the downside of keeping it?

Good question!
How about add DMI_BIOS_VERSION for BIOS DMI_MATCH.  For example,
DMI_MATCH(DMI_BIOS_VERSION, "V1.0")

The BIOS versions listed on Acer website [1] are 1.04, 1.10 ...
The reboot issue is fixed since BIOS 1.08.  So, the only the string
like "V1.0*" should apply the quirk.

But, that will raise another question:  Since the original quirk works
for all Acer X514-51T and the quirk cannot be removed for older BIOS.
Why not keep only original matching items for all Acer X514-51T
laptops?

I am not sure which option is better.  Any comment?

[1] https://www.acer.com/ac/en/US/content/support-product/7889?b=3D1

BR,
Jian-Hong Pan