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To:     LKML <linux-kernel@vger.kernel.org>, linux-mm@kvack.org
From:   Meelis Roos <mroos@linux.ee>
Subject: CONFIG_DEBUG_VIRTUAL breaks boot on x86-32
Message-ID: <4d5ee3b0-6d47-a8df-a6b3-54b0fba66ed7@linux.ee>
Date:   Thu, 21 Mar 2019 22:22:43 +0200
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I tried to debug another problem and turned on most debug options for memory.
The resulting kernel failed to boot.

Bisecting the configurations led to CONFIG_DEBUG_VIRTUAL - if I turned it on
in addition to some other debug options, the machine crashed with

kernel BUG at arch/x86/mm/physaddr.c:79!

Screenshot at http://kodu.ut.ee/~mroos/debug_virtual-boot-hang-1.jpg

The machine was Athlon XP with VIA KT600 chipset and 2G RAM.

-- 
Meelis Roos <mroos@linux.ee>