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[142.68.80.239]) by smtp.gmail.com with ESMTPSA id w17-20020ae9e511000000b007856bff53d3sm3084439qkf.54.2024.02.13.09.21.29 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 13 Feb 2024 09:21:29 -0800 (PST) Received: from jgg by wakko with local (Exim 4.95) (envelope-from ) id 1rZwTI-005N9E-UB; Tue, 13 Feb 2024 13:21:28 -0400 Date: Tue, 13 Feb 2024 13:21:28 -0400 From: Jason Gunthorpe To: Shivaprasad G Bhat Cc: iommu@lists.linux.dev, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, mpe@ellerman.id.au, npiggin@gmail.com, christophe.leroy@csgroup.eu, aneesh.kumar@kernel.org, naveen.n.rao@linux.ibm.com, jroedel@suse.de, tpearson@raptorengineering.com, aik@amd.com, bgray@linux.ibm.com, gregkh@linuxfoundation.org, gbatra@linux.vnet.ibm.com, vaibhav@linux.ibm.com, venkat88@linux.vnet.ibm.com Subject: Re: [PATCH] powerpc/iommu: Fix the missing iommu_group_put() during platform domain attach Message-ID: <20240213172128.GM765010@ziepe.ca> References: <170784021983.6249.10039296655906636112.stgit@linux.ibm.com> Precedence: bulk X-Mailing-List: iommu@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <170784021983.6249.10039296655906636112.stgit@linux.ibm.com> On Tue, Feb 13, 2024 at 10:05:22AM -0600, Shivaprasad G Bhat wrote: > The function spapr_tce_platform_iommu_attach_dev() is missing to call > iommu_group_put() when the domain is already set. This refcount leak > shows up with BUG_ON() during DLPAR remove operation as, > > KernelBug: Kernel bug in state 'None': kernel BUG at arch/powerpc/platforms/pseries/iommu.c:100! > Oops: Exception in kernel mode, sig: 5 [#1] > LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=8192 NUMA pSeries > > Hardware name: IBM,9080-HEX POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1060.00 (NH1060_016) hv:phyp pSeries > NIP: c0000000000ff4d4 LR: c0000000000ff4cc CTR: 0000000000000000 > REGS: c0000013aed5f840 TRAP: 0700 Tainted: G I (6.8.0-rc3-autotest-g99bd3cb0d12e) > MSR: 8000000000029033 CR: 44002402 XER: 20040000 > CFAR: c000000000a0d170 IRQMASK: 0 > GPR00: c0000000000ff4cc c0000013aed5fae0 c000000001512700 c0000013aa362138 > GPR04: 0000000000000000 0000000000000000 0000000000000000 0000000119c8afd0 > GPR08: 0000000000000000 c000001284442b00 0000000000000001 0000000000001003 > GPR12: 0000000300000000 c0000018ffff2f00 0000000000000000 0000000000000000 > GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > GPR24: c0000013aed5fc40 0000000000000002 0000000000000000 c000000002757d90 > GPR28: c0000000000ff440 c000000002757cb8 c00000183799c1a0 c0000013aa362b00 > NIP [c0000000000ff4d4] iommu_reconfig_notifier+0x94/0x200 > LR [c0000000000ff4cc] iommu_reconfig_notifier+0x8c/0x200 > Call Trace: > [c0000013aed5fae0] [c0000000000ff4cc] iommu_reconfig_notifier+0x8c/0x200 (unreliable) > [c0000013aed5fb10] [c0000000001a27b0] notifier_call_chain+0xb8/0x19c > [c0000013aed5fb70] [c0000000001a2a78] blocking_notifier_call_chain+0x64/0x98 > [c0000013aed5fbb0] [c000000000c4a898] of_reconfig_notify+0x44/0xdc > [c0000013aed5fc20] [c000000000c4add4] of_detach_node+0x78/0xb0 > [c0000013aed5fc70] [c0000000000f96a8] ofdt_write.part.0+0x86c/0xbb8 > [c0000013aed5fce0] [c00000000069b4bc] proc_reg_write+0xf4/0x150 > [c0000013aed5fd10] [c0000000005bfeb4] vfs_write+0xf8/0x488 > [c0000013aed5fdc0] [c0000000005c0570] ksys_write+0x84/0x140 > [c0000013aed5fe10] [c000000000033358] system_call_exception+0x138/0x330 > [c0000013aed5fe50] [c00000000000d05c] system_call_vectored_common+0x15c/0x2ec > --- interrupt: 3000 at 0x20000433acb4 > > ---[ end trace 0000000000000000 ]--- > > The patch adds the missing iommu_group_put() call. > > Fixes: a8ca9fc9134c ("powerpc/iommu: Do not do platform domain attach atctions after probe") > Signed-off-by: Shivaprasad G Bhat > --- > arch/powerpc/kernel/iommu.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) Doh, that is a weird splat for this but thanks for finding it Reviewed-by: Jason Gunthorpe Jason From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 05912C4829F for ; 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[142.68.80.239]) by smtp.gmail.com with ESMTPSA id w17-20020ae9e511000000b007856bff53d3sm3084439qkf.54.2024.02.13.09.21.29 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 13 Feb 2024 09:21:29 -0800 (PST) Received: from jgg by wakko with local (Exim 4.95) (envelope-from ) id 1rZwTI-005N9E-UB; Tue, 13 Feb 2024 13:21:28 -0400 Date: Tue, 13 Feb 2024 13:21:28 -0400 From: Jason Gunthorpe To: Shivaprasad G Bhat Subject: Re: [PATCH] powerpc/iommu: Fix the missing iommu_group_put() during platform domain attach Message-ID: <20240213172128.GM765010@ziepe.ca> References: <170784021983.6249.10039296655906636112.stgit@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <170784021983.6249.10039296655906636112.stgit@linux.ibm.com> X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: venkat88@linux.vnet.ibm.com, jroedel@suse.de, gbatra@linux.vnet.ibm.com, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, aneesh.kumar@kernel.org, tpearson@raptorengineering.com, iommu@lists.linux.dev, npiggin@gmail.com, bgray@linux.ibm.com, naveen.n.rao@linux.ibm.com, vaibhav@linux.ibm.com, linuxppc-dev@lists.ozlabs.org, aik@amd.com Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Tue, Feb 13, 2024 at 10:05:22AM -0600, Shivaprasad G Bhat wrote: > The function spapr_tce_platform_iommu_attach_dev() is missing to call > iommu_group_put() when the domain is already set. This refcount leak > shows up with BUG_ON() during DLPAR remove operation as, > > KernelBug: Kernel bug in state 'None': kernel BUG at arch/powerpc/platforms/pseries/iommu.c:100! > Oops: Exception in kernel mode, sig: 5 [#1] > LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=8192 NUMA pSeries > > Hardware name: IBM,9080-HEX POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1060.00 (NH1060_016) hv:phyp pSeries > NIP: c0000000000ff4d4 LR: c0000000000ff4cc CTR: 0000000000000000 > REGS: c0000013aed5f840 TRAP: 0700 Tainted: G I (6.8.0-rc3-autotest-g99bd3cb0d12e) > MSR: 8000000000029033 CR: 44002402 XER: 20040000 > CFAR: c000000000a0d170 IRQMASK: 0 > GPR00: c0000000000ff4cc c0000013aed5fae0 c000000001512700 c0000013aa362138 > GPR04: 0000000000000000 0000000000000000 0000000000000000 0000000119c8afd0 > GPR08: 0000000000000000 c000001284442b00 0000000000000001 0000000000001003 > GPR12: 0000000300000000 c0000018ffff2f00 0000000000000000 0000000000000000 > GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > GPR24: c0000013aed5fc40 0000000000000002 0000000000000000 c000000002757d90 > GPR28: c0000000000ff440 c000000002757cb8 c00000183799c1a0 c0000013aa362b00 > NIP [c0000000000ff4d4] iommu_reconfig_notifier+0x94/0x200 > LR [c0000000000ff4cc] iommu_reconfig_notifier+0x8c/0x200 > Call Trace: > [c0000013aed5fae0] [c0000000000ff4cc] iommu_reconfig_notifier+0x8c/0x200 (unreliable) > [c0000013aed5fb10] [c0000000001a27b0] notifier_call_chain+0xb8/0x19c > [c0000013aed5fb70] [c0000000001a2a78] blocking_notifier_call_chain+0x64/0x98 > [c0000013aed5fbb0] [c000000000c4a898] of_reconfig_notify+0x44/0xdc > [c0000013aed5fc20] [c000000000c4add4] of_detach_node+0x78/0xb0 > [c0000013aed5fc70] [c0000000000f96a8] ofdt_write.part.0+0x86c/0xbb8 > [c0000013aed5fce0] [c00000000069b4bc] proc_reg_write+0xf4/0x150 > [c0000013aed5fd10] [c0000000005bfeb4] vfs_write+0xf8/0x488 > [c0000013aed5fdc0] [c0000000005c0570] ksys_write+0x84/0x140 > [c0000013aed5fe10] [c000000000033358] system_call_exception+0x138/0x330 > [c0000013aed5fe50] [c00000000000d05c] system_call_vectored_common+0x15c/0x2ec > --- interrupt: 3000 at 0x20000433acb4 > > ---[ end trace 0000000000000000 ]--- > > The patch adds the missing iommu_group_put() call. > > Fixes: a8ca9fc9134c ("powerpc/iommu: Do not do platform domain attach atctions after probe") > Signed-off-by: Shivaprasad G Bhat > --- > arch/powerpc/kernel/iommu.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) Doh, that is a weird splat for this but thanks for finding it Reviewed-by: Jason Gunthorpe Jason