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;
Date:   Sat, 25 May 2019 17:40:52 +0800
From:   Gen Zhang <blackgod016574@gmail.com>
To:     Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc:     Darren Hart <dvhart@infradead.org>,
        linux-efi <linux-efi@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2] efi_64: Fix a missing-check bug in
 arch/x86/platform/efi/efi_64.c
Message-ID: <20190525094052.GA13189@zhanggen-UX430UQ>
References: <20190517082633.GA3890@zhanggen-UX430UQ>
 <CAKv+Gu98JNK34Q6MNOe3aq0W5rbv6hUFiuc7cHxHJat5aTk_gg@mail.gmail.com>
 <20190517090628.GA4162@zhanggen-UX430UQ>
 <CAKv+Gu_mwFpdtNZm9QMFn69+vOMTOpv9gvuhnBL2NBXvwkhXqg@mail.gmail.com>
 <20190523005133.GA14881@zhanggen-UX430UQ>
 <CAKv+Gu_wRYZdDYXso0B5m_BPJznGQXpCWq4_0u34bConu0V1ow@mail.gmail.com>
 <20190525023608.GA11613@zhanggen-UX430UQ>
 <CAKv+Gu-agMymoGm0G8Yj-siXwtPnqYjAHeu-wQwRT47Jqd27JA@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <CAKv+Gu-agMymoGm0G8Yj-siXwtPnqYjAHeu-wQwRT47Jqd27JA@mail.gmail.com>
User-Agent: Mutt/1.5.24 (2015-08-30)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Sat, May 25, 2019 at 11:18:36AM +0200, Ard Biesheuvel wrote:
> On Sat, 25 May 2019 at 04:36, Gen Zhang <blackgod016574@gmail.com> wrote:
> >
> > On Fri, May 24, 2019 at 06:07:10PM +0200, Ard Biesheuvel wrote:
> > > Apologies for only spotting this now, but I seem to have given some bad advice.
> > >
> > > efi_call_phys_prolog() in efi_64.c will also return NULL if
> > > (!efi_enabled(EFI_OLD_MEMMAP)), but this is not an error condition. So
> > > that occurrence has to be updated: please return efi_mm.pgd instead.
> > Thanks for your reply, Ard. You mean that we should return efi_mm.pgd
> > when allcoation fails? And we should delete return EFI_ABORTED on the
> > caller site, right? In that case, how should we handle the NULL pointer
> > returned by condition if(!efi_enabled(EFI_OLD_MEMMAP)) on the caller
> > site?
> >
> 
> No, the other way around. I have already updated the patch, so don't
> worry about it.
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/efi/efi.git/commit/?h=urgent&id=d2dc2bc7b60b936b95da4b04c2912c02974c3e9f
Thanks for your reply and update, Ard! That's really nice of you.

Thanks
Gen