From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yunsheng Lin Date: Sat, 12 Oct 2019 09:47:56 +0000 Subject: Re: [PATCH v6] numa: make node_to_cpumask_map() NUMA_NO_NODE aware Message-Id: <1e1ec851-b5e7-8f35-a627-4c12ca9c2d3c@huawei.com> List-Id: References: <20190924131939.GS23050@dhcp22.suse.cz> <1adcbe68-6753-3497-48a0-cc84ac503372@huawei.com> <20190925104108.GE4553@hirez.programming.kicks-ass.net> <47fa4cee-8528-7c23-c7de-7be1b65aa2ae@huawei.com> <20191010073212.GB18412@dhcp22.suse.cz> <6cc94f9b-0d79-93a8-5ec2-4f6c21639268@huawei.com> <20191011111539.GX2311@hirez.programming.kicks-ass.net> <7fad58d6-5126-e8b8-a7d8-a91814da53ba@huawei.com> <20191012074014.GA2037204@kroah.com> In-Reply-To: <20191012074014.GA2037204@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Greg KH Cc: Peter Zijlstra , Michal Hocko , Robin Murphy , catalin.marinas@arm.com, will@kernel.org, mingo@redhat.com, bp@alien8.de, rth@twiddle.net, ink@jurassic.park.msu.ru, mattst88@gmail.com, benh@kernel.crashing.org, paulus@samba.org, mpe@ellerman.id.au, heiko.carstens@de.ibm.com, gor@linux.ibm.com, borntraeger@de.ibm.com, ysato@users.sourceforge.jp, dalias@libc.org, davem@davemloft.net, ralf@linux-mips.org, paul.burton@mips.com, jhogan@kernel.org, jiaxun.yang@flygoat.com, chenhc@lemote.com, akpm@linux-foundation.org, rppt@linux.ibm.com, anshuman.khandual@arm.com, tglx@linutronix.de, cai@lca.pw, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, hpa@zytor.com, x86@kernel.org, dave.hansen@linux.intel.com, luto@kernel.org, len.brown@intel.com, axboe@kernel.dk, dledford@redhat.com, jeffrey.t.kirsher@intel.com, linux-alpha@vger.kernel.org, naveen.n.rao@linux.vnet.ibm.com, mwb@linux.vnet.ibm.com, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, tbogendoerfer@suse.de, linux-mips@vger.kernel.org, rafael@kernel.org, bhelgaas@google.com, linux-pci@vger.kernel.org, "Rafael J. Wysocki" , lenb@kernel.org, linux-acpi@vger.kernel.org On 2019/10/12 15:40, Greg KH wrote: > On Sat, Oct 12, 2019 at 02:17:26PM +0800, Yunsheng Lin wrote: >> add pci and acpi maintainer >> cc linux-pci@vger.kernel.org and linux-acpi@vger.kernel.org >> >> On 2019/10/11 19:15, Peter Zijlstra wrote: >>> On Fri, Oct 11, 2019 at 11:27:54AM +0800, Yunsheng Lin wrote: >>>> But I failed to see why the above is related to making node_to_cpumask_map() >>>> NUMA_NO_NODE aware? >>> >>> Your initial bug is for hns3, which is a PCI device, which really _MUST_ >>> have a node assigned. >>> >>> It not having one, is a straight up bug. We must not silently accept >>> NO_NODE there, ever. >>> >> >> I suppose you mean reporting a lack of affinity when the node of a pcie >> device is not set by "not silently accept NO_NODE". > > If the firmware of a pci device does not provide the node information, > then yes, warn about that. > >> As Greg has asked about in [1]: >> what is a user to do when the user sees the kernel reporting that? >> >> We may tell user to contact their vendor for info or updates about >> that when they do not know about their system well enough, but their >> vendor may get away with this by quoting ACPI spec as the spec >> considering this optional. Should the user believe this is indeed a >> fw bug or a misreport from the kernel? > > Say it is a firmware bug, if it is a firmware bug, that's simple. > >> If this kind of reporting is common pratice and will not cause any >> misunderstanding, then maybe we can report that. > > Yes, please do so, that's the only way those boxes are ever going to get > fixed. And go add the test to the "firmware testing" tool that is based > on Linux that Intel has somewhere, to give vendors a chance to fix this > before they ship hardware. > > This shouldn't be a big deal, we warn of other hardware bugs all the > time. Ok, thanks for clarifying. Will send a patch to catch the case when a pcie device without numa node being set and warn about it. Maybe use dev->bus to verify if it is a pci device? > > thanks, > > greg k-h > > . >