From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ozlabs.org (ozlabs.org [IPv6:2401:3900:2:1::2]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3y7n3c33hWzDqhg for ; Fri, 6 Oct 2017 22:10:04 +1100 (AEDT) In-Reply-To: <20170907050551.4632-1-anton@ozlabs.org> To: Anton Blanchard , benh@kernel.crashing.org, paulus@samba.org, bharata@linux.vnet.ibm.com, arbab@linux.vnet.ibm.com, npiggin@gmail.com, mikey@neuling.org, cyrilbur@gmail.com, aneesh.kumar@linux.vnet.ibm.com From: Michael Ellerman Cc: linuxppc-dev@lists.ozlabs.org Subject: Re: powerpc/powernv: Increase memory block size to 1GB on radix Message-Id: <3y7n3c2442z9t4b@ozlabs.org> Date: Fri, 6 Oct 2017 22:10:04 +1100 (AEDT) List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Thu, 2017-09-07 at 05:05:51 UTC, Anton Blanchard wrote: > From: Anton Blanchard > > Memory hot unplug on PowerNV radix hosts is broken. Our memory block > size is 256MB but since we map the linear region with very large pages, > each pte we tear down maps 1GB. > > A hot unplug of one 256MB memory block results in 768MB of memory > getting unintentionally unmapped. At this point we are likely to oops. > > Fix this by increasing our memory block size to 1GB on PowerNV radix > hosts. > > Signed-off-by: Anton Blanchard Applied to powerpc fixes, thanks. https://git.kernel.org/powerpc/c/53ecde0b9126ff140abe3aefd7f0ec cheers