Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753051AbbBYKA6 (ORCPT ); Wed, 25 Feb 2015 05:00:58 -0500 Received: from foss-mx-na.foss.arm.com ([217.140.108.86]:44574 "EHLO foss-mx-na.foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751293AbbBYKA4 (ORCPT ); Wed, 25 Feb 2015 05:00:56 -0500 Date: Wed, 25 Feb 2015 10:00:45 +0000 From: Will Deacon To: Geert Uytterhoeven Cc: Laurent Pinchart , Vincent =?iso-8859-1?Q?Stehl=E9?= , "iommu@lists.linux-foundation.org" , Linux-Next , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" Subject: Re: [PATCH linux-next] iommu: Enable LPAE pagetable on ARM only Message-ID: <20150225100044.GC20673@arm.com> References: <1424621346-7822-1-git-send-email-vincent.stehle@laposte.net> <2868840.GyWYJOzqWH@avalon> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3919 Lines: 100 On Tue, Feb 24, 2015 at 10:33:02AM +0000, Geert Uytterhoeven wrote: > On Mon, Feb 23, 2015 at 5:52 PM, Laurent Pinchart > wrote: > > On Sunday 22 February 2015 17:09:06 Vincent Stehl? wrote: > >> LPAE iommu page table makes sense only for ARM architecture. Add the > >> corresponding dependency in Kconfig. > >> > >> This fixes the following runtime warnings on PA-RISC architecture: > > > > I suppose this is caused by the selftest code ? > > > >> WARNING: at drivers/iommu/io-pgtable-arm.c:413 > >> Modules linked in: > >> CPU: 0 PID: 1 Comm: swapper/0 Not tainted > >> 3.19.0-next-20150222-00002-gc420256 #2 task: 17ca0000 ti: 17ca8000 task.ti: > >> 17ca8000 > >> > >> YZrvWESTHLNXBCVMcbcbcbcbOGFRQPDI > >> PSW: 00000000000001001111111100001111 Not tainted > >> r00-03 0004ff0f 0000001b 104871b0 17ca83c0 > >> r04-07 00001000 00000000 00000000 00000000 > >> r08-11 00000000 40001000 1013b36c 17ca8248 > >> r12-15 00000080 17e712c0 00000000 17c5e100 > >> r16-19 0000000c 105d8eb0 40001000 ffffffff > >> r20-23 00000000 00800020 1048717c 00000000 > >> r24-27 00001000 00000000 00000009 10774ce0 > >> r28-31 00000000 00000027 17ca8480 10486d44 > >> sr00-03 00000000 00000000 00000000 00000000 > >> sr04-07 00000000 00000000 00000000 00000000 > >> > >> IASQ: 00000000 00000000 IAOQ: 10486df4 10486df8 > >> IIR: 03ffe01f ISR: 00000000 IOR: 17c86e54 > >> CPU: 0 CR30: 17ca8000 CR31: 00000002 > >> ORIG_R28: 00000001 > >> IAOQ[0]: __arm_lpae_unmap+0x144/0x4cc > >> IAOQ[1]: __arm_lpae_unmap+0x148/0x4cc > >> RP(r2): arm_lpae_unmap+0x34/0x6c > >> Backtrace: > >> [<104871b0>] arm_lpae_unmap+0x34/0x6c > >> [<10127944>] 0x10127944 > >> [<10168ee0>] do_one_initcall+0x128/0x1dc > >> [<101028fc>] 0x101028fc > >> [<10161b48>] kernel_init+0x1c/0x118 > >> [<1015d01c>] end_fault_vector+0x1c/0x24 > >> [<101762ec>] save_stack_trace+0x28/0x60 > >> > >> Signed-off-by: Vincent Stehl? > >> Cc: Laurent Pinchart > >> Cc: Will Deacon > >> --- > >> > >> > >> Hi, > >> > >> This can be seen with e.g. Linux next-20150222 on parisc with allmodconfig. > >> > >> Best regards, > >> > >> V. > >> > >> > >> drivers/iommu/Kconfig | 1 + > >> 1 file changed, 1 insertion(+) > >> > >> diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig > >> index baa0d97..c73fd72 100644 > >> --- a/drivers/iommu/Kconfig > >> +++ b/drivers/iommu/Kconfig > >> @@ -22,6 +22,7 @@ config IOMMU_IO_PGTABLE > >> > >> config IOMMU_IO_PGTABLE_LPAE > >> bool "ARMv7/v8 Long Descriptor Format" > >> + depends on ARM > > > > How about ARM || COMPILE_TEST ? It can still be useful to compile the module > > on other architectures. > > COMPILE_TEST is meant for test-compiling drivers or subsystems that are not > useful on all platforms. IMHO COMPILE_TEST kernels are still supposed to boot > without ill effects. > > Now, I understand the issue on PA-RISC is with the selftest, not with the actual > IOMMU_IO_PGTABLE_LPAE module? Then IOMMU_IO_PGTABLE_LPAE > can depend on ARM || COMPILE_TEST (|| ARM64, cfr. Laurent's later email). > > But the selftest should protect itself against running on non-ARM, either > by making IOMMU_IO_PGTABLE_LPAE_SELFTEST depend on ARM(64) > (without "|| COMPILE_TEST"), or by adding a check to arm_lpae_do_selftests(), > to please all compile-testers. Perhaps, but actually the issues reported by the self-test are *real* bugs that I've now got fixes for. They just don't show up on arm platforms because of different right shift behaviour. Will -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/