From 274259391c14166fcabae74f9fc0104223ff27a1 Mon Sep 17 00:00:00 2001 From: Breno Leitao Date: Thu, 11 Jun 2026 04:55:13 -0700 Subject: [PATCH] cacheinfo: don't propagate DT/ACPI error when arch supplies info (arm64) cache_setup_properties() sets use_arch_info = true when DT/ACPI provide no cache nodes and the arch can derive the topology from CPU registers (e.g. arm64 reading CLIDR_EL1), but still returns the original -ENOENT. cache_shared_cpu_map_setup() bails on that error before the new flag can take effect, so the first CPU brought online always trips a misleading warning: cacheinfo: Unable to detect cache hierarchy for CPU 0 Subsequent CPUs skip cache_setup_properties() entirely because use_arch_info is now true, which is why only CPU0 hits it. This is reproducible on arm64 with the QEMU 'virt' machine, whose default DT has no cache nodes. Clear ret after setting use_arch_info so the caller proceeds and populates the shared cpu map via the arch-supplied leaves. Fixes: ef9f643a9f8b ("cacheinfo: Add use_arch[|_cache]_info field/function") Reviewed-by: Pierre Gondois Signed-off-by: Breno Leitao Reviewed-by: Sudeep Holla Link: https://patch.msgid.link/20260611-cacheinfo-v2-1-6069ef066cf3@debian.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/cacheinfo.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/base/cacheinfo.c b/drivers/base/cacheinfo.c index 70701d3bc81c..9f9c72727a05 100644 --- a/drivers/base/cacheinfo.c +++ b/drivers/base/cacheinfo.c @@ -401,9 +401,14 @@ static int cache_setup_properties(unsigned int cpu) else if (!acpi_disabled) ret = cache_setup_acpi(cpu); - // Assume there is no cache information available in DT/ACPI from now. - if (ret && use_arch_cache_info()) + /* + * No DT/ACPI cache nodes; fall back to arch-derived topology (e.g. + * arm64 CLIDR_EL1) and clear the error to avoid a spurious warning. + */ + if (ret && use_arch_cache_info()) { use_arch_info = true; + ret = 0; + } return ret; }