From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f69.google.com (mail-pa0-f69.google.com [209.85.220.69]) by kanga.kvack.org (Postfix) with ESMTP id BA1CA6B0005 for ; Mon, 20 Jun 2016 20:40:58 -0400 (EDT) Received: by mail-pa0-f69.google.com with SMTP id b13so1469132pat.3 for ; Mon, 20 Jun 2016 17:40:58 -0700 (PDT) Received: from ozlabs.org (ozlabs.org. [2401:3900:2:1::2]) by mx.google.com with ESMTPS id pj9si3491338pac.4.2016.06.20.17.40.57 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 20 Jun 2016 17:40:57 -0700 (PDT) In-Reply-To: <1462958539-25552-1-git-send-email-oohall@gmail.com> From: Michael Ellerman Subject: Re: [v2] powerpc/mm: Ensure "special" zones are empty Message-Id: <3rYTRT6gDSz9t0f@ozlabs.org> Date: Tue, 21 Jun 2016 10:40:53 +1000 (AEST) Sender: owner-linux-mm@kvack.org List-ID: To: Oliver O'Halloran , linuxppc-dev@lists.ozlabs.org Cc: linux-mm@kvack.org On Wed, 2016-11-05 at 09:22:18 UTC, Oliver O'Halloran wrote: > The mm zone mechanism was traditionally used by arch specific code to > partition memory into allocation zones. However there are several zones > that are managed by the mm subsystem rather than the architecture. Most > architectures set the max PFN of these special zones to zero, however on > powerpc we set them to ~0ul. This, in conjunction with a bug in > free_area_init_nodes() results in all of system memory being placed in > ZONE_DEVICE when enabled. Device memory cannot be used for regular kernel > memory allocations so this will cause a kernel panic at boot. Given the > planned addition of more mm managed zones (ZONE_CMA) we should aim to be > consistent with every other architecture and set the max PFN for these > zones to zero. > > Signed-off-by: Oliver O'Halloran > Reviewed-by: Balbir Singh > Cc: linux-mm@kvack.org Applied to powerpc next, thanks. https://git.kernel.org/powerpc/c/3079abe555511031e2ba5d1e21 cheers -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org