From mboxrd@z Thu Jan 1 00:00:00 1970 From: lersek@redhat.com (Laszlo Ersek) Date: Fri, 14 Oct 2016 17:27:58 +0200 Subject: aarch64 ACPI boot regressed by commit 7ba5f605f3a0 ("arm64/numa: remove the limitation that cpu0 must bind to node0") In-Reply-To: References: <4a64cd93-5ead-aad6-1057-f42224d65b43@redhat.com> <20161014080524.4hm2b4p373r7rhel@hawk.localdomain> <04f22a79-301b-f05b-033d-c7a24c9f4084@redhat.com> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 10/14/16 17:01, Laszlo Ersek wrote: > Maybe the code I > tried to analyze in this email was never *meant* to associate CPU#0 with > any NUMA node at all (not even node 0); instead, other code -- for > example code removed by 7ba5f605f3a0 -- was meant to perform that > association. Staring a bit more at the code, this looks very likely; in acpi_map_gic_cpu_interface() we have > /* Check if GICC structure of boot CPU is available in the MADT */ > if (cpu_logical_map(0) == hwid) { > if (bootcpu_valid) { > pr_err("duplicate boot CPU MPIDR: 0x%llx in MADT\n", > hwid); > return; > } > bootcpu_valid = true; > return; > } which means that this callback function (for parsing the GICC structures in the MADT) expects to find the boot processor as well. Upon finding the boot processor, we set bootcpu_valid to true, and that's it -- no association with any NUMA node, and no incrementing of "cpu_count". Thanks Laszlo