From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757053AbcA2Vyw (ORCPT ); Fri, 29 Jan 2016 16:54:52 -0500 Received: from mout.kundenserver.de ([217.72.192.74]:59039 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756854AbcA2Vyt (ORCPT ); Fri, 29 Jan 2016 16:54:49 -0500 From: Arnd Bergmann To: Geert Uytterhoeven Cc: Russell King - ARM Linux , Fengguang Wu , Linux-Arch , Linux MIPS Mailing List , James Hogan , Paul Burton , linux-kbuild , Heinrich Schuchardt , "linux-kernel@vger.kernel.org" , Ralf Baechle , Florian Fainelli , Michal Marek , "linux-arm-kernel@lists.infradead.org" Subject: Re: [linux-review:James-Hogan/kbuild-Remove-stale-asm-generic-wrappers/20160119-183642] d979f99e9cc14e2667e9b6e268db695977e4197a BUILD DONE Date: Fri, 29 Jan 2016 22:54:02 +0100 Message-ID: <4727572.ddrMioV3Fi@wuerfel> User-Agent: KMail/4.11.5 (Linux/3.16.0-10-generic; KDE/4.11.5; x86_64; ; ) In-Reply-To: References: <569e1dbb.MgLv8OaZwklOxxtU%fengguang.wu@intel.com> <19656457.qoKNGRmV4Q@wuerfel> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-Provags-ID: V03:K0:8MwsxqK3HlAEI25xJvpxA04oq44XHdAbEHbI3z3/ySwJhj708S7 Ot3OkLsHIFLO4yW2ZWSyVnE2QZARVpjGJQQS1JQUUiEPF2yvO9wifAK8D7fhpD7PUbvdTvi trDELElCzhUpI4z0srQzZJpTLqDlAVetep4A8YYe2bn7b+2SctXjJYhsJ1ICHpEc1eBtNdU gaDiQMCk4Pzs84Z49uc9A== X-UI-Out-Filterresults: notjunk:1;V01:K0:6zO3R664FxI=:ATf3iaG3u5ZtNaf8sVmlIU 8MXPFIhsDFztW7fXi30PuGihxG1CzpgMRcQyhoniTn356gTvyBoDwcLkEvmwfmcWrtnk1xrA4 R64Aj+uC6qBce//10gcdY6FdSL5SInbSCVcRfgPfSkpSx39+aQzvIZiP61HeeAwS78yr9lO29 nZ29X5z39jl2TjWXF/emZeCBzXOBIf3R7ai8k8Av9xP88/3Q7GSf2p+IaLFfUkaUAQk9kLpqZ MTMv0J3o9eQqhR/LDGK/ngBYNXiTsbwtZvwB2A4EcCXJCceHQ3G/oQWQDVPTfhBJTmFZ4qTCt +VlkeZeV1SyN8OPMT6u/sRCLSYRlGyG//QT48NXXiIJec7UbISFx4hXyYCeIZhMMFWvdsydOq e8pShl3SeBagBU85okOJVH+WPdA8zmn0Wz4JhYzK18LrtdXbG+4CErGGwiDKtHYF3N+mWfimW tHMLNtuONoJ7ZChj7YOPZ5TJmBKB0PdVIy3HS1pOJYARkj9iyLIDMLCfXtd3t30JVEBwS0bOW 4GMd3wYQp++jbhR1vCM6dXFF1JzreYjfGE/SuH4AGjj+ums0gx1rh+yGbpiJBNAzRPPgzXRKZ oRD3WVd8C2ox4a8agr/MrGmf34+xhcFaWEmWq36KkNjjOAN7q0/fiKInY3yQCS378t/imw95P 10sawF2YzUjZYvHeuvxN+UE3vFScCF5xdEyGqZYVp8gMTccUuuIWg1Qs0h9QdOZGasPA/psKz 0/UtnD4M4/7JDl/v Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Friday 29 January 2016 22:24:31 Geert Uytterhoeven wrote: > > diff --git a/arch/arm/include/debug/8250.S b/arch/arm/include/debug/8250.S > > index 7f7446f6f806..1191b1458586 100644 > > --- a/arch/arm/include/debug/8250.S > > +++ b/arch/arm/include/debug/8250.S > > @@ -9,6 +9,9 @@ > > */ > > #include > > > > +#if CONFIG_DEBUG_UART_PHYS == 0xdeadbeef || CONFIG_DEBUG_UART_VIRT < 0xe0000000 > > Any special reason for 0xe0000000 vs ... > > > --- a/arch/arm/include/debug/efm32.S > > +++ b/arch/arm/include/debug/efm32.S > > @@ -6,6 +6,9 @@ > > * it under the terms of the GNU General Public License version 2 as > > * published by the Free Software Foundation. > > */ > > +#if CONFIG_DEBUG_UART_PHYS == 0xdeadbeef || CONFIG_DEBUG_UART_VIRT < 0xf0000000 > > 0xf0000000? We have one platform that uses a 8250 at address 0xe0010fe0, and one using the netx UART at virtual address 0xe0000a00, everything else uses 0xf0000000 or higher. The 0xf0000000 address seems like a better default cutoff, because that is close to the VMALLOC_START value for systems with 768MB of RAM or more. Picking a lower number can easily get you in trouble here. Now that I think about it, I guess platforms that use values above 0xfee00000 can also easily get into trouble as that conflicts with the PCI I/O space, the fixmap or other special areas documented in Documentation/arm/memory.txt. We have a bunch of those: default 0xfee003f8 if DEBUG_FOOTBRIDGE_COM1 default 0xfee20000 if DEBUG_NSPIRE_CLASSIC_UART || DEBUG_NSPIRE_CX_UART default 0xfee82340 if ARCH_IOP13XX default 0xfef00000 if ARCH_IXP4XX && !CPU_BIG_ENDIAN default 0xfef00003 if ARCH_IXP4XX && CPU_BIG_ENDIAN default 0xfef36000 if DEBUG_HIGHBANK_UART default 0xfefb0000 if DEBUG_OMAP1UART1 || DEBUG_OMAP7XXUART1 default 0xfefb0800 if DEBUG_OMAP1UART2 || DEBUG_OMAP7XXUART2 default 0xfefb9800 if DEBUG_OMAP1UART3 || DEBUG_OMAP7XXUART3 default 0xfefff700 if ARCH_IOP33X default 0xff003000 if DEBUG_U300_UART default 0xffd01000 if DEBUG_HIP01_UART The HIP01 is the only one that looks actively dangerous here (clashes with fixmap), the others are probably all fine but it would be nice to stay out of that area completely. Arnd