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Date:   Fri, 29 May 2020 19:11:04 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Thomas Gleixner <tglx@linutronix.de>
Cc:     Dmitry Vyukov <dvyukov@google.com>,
        syzbot <syzbot+dc1fa714cb070b184db5@syzkaller.appspotmail.com>,
        LKML <linux-kernel@vger.kernel.org>,
        syzkaller-bugs <syzkaller-bugs@googlegroups.com>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        the arch/x86 maintainers <x86@kernel.org>,
        Oleg Nesterov <oleg@redhat.com>
Subject: Re: PANIC: double fault in fixup_bad_iret
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On Fri, May 29, 2020 at 06:07:11PM +0200, Peter Zijlstra wrote:

> Like with KCSAN, we should blanket kill KASAN/UBSAN and friends (at the
> very least in arch/x86/) until they get that function attribute stuff
> sorted.

Something like so.

---
diff --git a/arch/x86/Makefile b/arch/x86/Makefile
index 00e378de8bc0..a90d32b87d7e 100644
--- a/arch/x86/Makefile
+++ b/arch/x86/Makefile
@@ -1,6 +1,14 @@
 # SPDX-License-Identifier: GPL-2.0
 # Unified Makefile for i386 and x86_64
 
+#
+# Until such a time that __no_kasan and __no_ubsan work as expected (and are
+# made part of noinstr), don't sanitize anything.
+#
+KASAN_SANITIZE := n
+UBSAN_SANITIZE := n
+KCOV_INSTRUMENT := n
+
 # select defconfig based on actual architecture
 ifeq ($(ARCH),x86)
   ifeq ($(shell uname -m),x86_64)