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Subject: Re: KASAN: slab-out-of-bounds Read in fbcon_get_font
To:     Paolo Bonzini <pbonzini@redhat.com>,
        Dmitry Vyukov <dvyukov@google.com>
Cc:     syzbot <syzbot+4455ca3b3291de891abc@syzkaller.appspotmail.com>,
        Andrey Ryabinin <aryabinin@virtuozzo.com>,
        Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>,
        Daniel Thompson <daniel.thompson@linaro.org>,
        Daniel Vetter <daniel.vetter@ffwll.ch>,
        DRI <dri-devel@lists.freedesktop.org>, ghalat@redhat.com,
        Gleb Natapov <gleb@kernel.org>, gwshan@linux.vnet.ibm.com,
        "H. Peter Anvin" <hpa@zytor.com>, James Morris <jmorris@namei.org>,
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        linux-security-module <linux-security-module@vger.kernel.org>,
        Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Ingo Molnar <mingo@redhat.com>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Russell Currey <ruscur@russell.cc>,
        Sam Ravnborg <sam@ravnborg.org>,
        "Serge E. Hallyn" <serge@hallyn.com>, stewart@linux.vnet.ibm.com,
        syzkaller-bugs <syzkaller-bugs@googlegroups.com>,
        Kentaro Takeda <takedakn@nttdata.co.jp>,
        Thomas Gleixner <tglx@linutronix.de>,
        the arch/x86 maintainers <x86@kernel.org>
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From:   Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Message-ID: <397ad276-ee2b-3883-9ed4-b5b1a2f8cf67@i-love.sakura.ne.jp>
Date:   Thu, 5 Dec 2019 19:41:18 +0900
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On 2019/12/05 19:22, Paolo Bonzini wrote:
> Ah, and because the machine is a KVM guest, kvm_wait appears in a lot of
> backtrace and I get to share syzkaller's joy every time. :)
> 
> This bisect result is bogus, though Tetsuo found the bug anyway.
> Perhaps you can exclude commits that only touch architectures other than
> x86?
> 

It would be nice if coverage functionality can extract filenames in the source
code and supply the list of filenames as arguments for bisect operation.

Also, (unrelated but) it would be nice if we can have "make yes2modconfig"
target which converts CONFIG_FOO=y to CONFIG_FOO=m if FOO is tristate.
syzbot is testing kernel configs close to "make allyesconfig" but I want to
save kernel rebuild time by disabling unrelated functionality when manually
"debug printk()ing" kernels.