Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Content-Type: text/plain;
        charset=utf-8
Mime-Version: 1.0 (Mac OS X Mail 13.0 \(3608.40.2.2.4\))
Subject: Re: [PATCH -next] efi/libstub/x86: fix an EFI server boot failure
From:   Qian Cai <cai@lca.pw>
In-Reply-To: <CAKv+Gu_snhTpsM4cjZ38UhH02v151NW4cJdQu9QVqCWu4rFVZw@mail.gmail.com>
Date:   Thu, 23 Jan 2020 14:49:14 -0500
Cc:     Ingo Molnar <mingo@redhat.com>, Ard Biesheuvel <ardb@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        linux-efi <linux-efi@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Content-Transfer-Encoding: quoted-printable
Message-Id: <10CCB37C-B91A-4A15-B9C0-5DBA5DD0BFD9@lca.pw>
References: <20200122191430.4888-1-cai@lca.pw>
 <CAKv+Gu_snhTpsM4cjZ38UhH02v151NW4cJdQu9QVqCWu4rFVZw@mail.gmail.com>
To:     Ard Biesheuvel <ard.biesheuvel@linaro.org>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk


> On Jan 22, 2020, at 2:17 PM, Ard Biesheuvel =
<ard.biesheuvel@linaro.org> wrote:
>=20
> On Wed, 22 Jan 2020 at 20:15, Qian Cai <cai@lca.pw> wrote:
>>=20
>> x86_64 EFI systems are unable to boot due to a typo in the recent =
commit.
>>=20
>> EFI config tables not found.
>> -- System halted
>>=20
>> Fixes: 796eb8d26a57 ("efi/libstub/x86: Use const attribute for =
efi_is_64bit()")
>> Signed-off-by: Qian Cai <cai@lca.pw>
>> ---
>> arch/x86/boot/compressed/eboot.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>=20
>> diff --git a/arch/x86/boot/compressed/eboot.c =
b/arch/x86/boot/compressed/eboot.c
>> index 82e26d0ff075..287393d725f0 100644
>> --- a/arch/x86/boot/compressed/eboot.c
>> +++ b/arch/x86/boot/compressed/eboot.c
>> @@ -32,7 +32,7 @@ __attribute_const__ bool efi_is_64bit(void)
>> {
>>        if (IS_ENABLED(CONFIG_EFI_MIXED))
>>                return efi_is64;
>> -       return IS_ENABLED(CONFIG_X64_64);
>> +       return IS_ENABLED(CONFIG_X86_64);
>> }
>>=20
>> static efi_status_t
>=20
> Apologies for the breakage - your fix is obviously correct. But I did
> test this code, so I am curious why I didn't see this problem. Are you
> booting via GRUB or from the UEFI shell? Can you share your .config
> please?

https://raw.githubusercontent.com/cailca/linux-mm/master/x86.config

BTW, this will also trigger a compilation breakage,

ld: arch/x86/platform/efi/efi_64.o: in function =
`efi_set_virtual_address_map':
efi_64.c:(.init.text+0x1419): undefined reference to `__efi64_thunk'
ld: efi_64.c:(.init.text+0x1530): undefined reference to =
`efi_uv1_memmap_phys_prolog'
ld: efi_64.c:(.init.text+0x1706): undefined reference to =
`efi_uv1_memmap_phys_epilog=E2=80=99

Likely due to the commit =E2=80=9Cefi/x86: avoid KASAN false positives =
when accessing the 1:1 mapping=E2=80=9D

Looks like you are in process fixing that one as well.=