6.6-stable review patch. If anyone has any objections, please let me know.
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From: Miquel Sabaté Solà mikisabate@gmail.com
[ Upstream commit 37233169a6ea912020c572f870075a63293b786a ]
When populating cache leaves we previously fetched the CPU device node at the very beginning. But when ACPI is enabled we go through a specific branch which returns early and does not call 'of_node_put' for the node that was acquired.
Since we are not using a CPU device node for the ACPI code anyways, we can simply move the initialization of it just passed the ACPI block, and we are guaranteed to have an 'of_node_put' call for the acquired node. This prevents a bad reference count of the CPU device node.
Moreover, the previous function did not check for errors when acquiring the device node, so a return -ENOENT has been added for that case.
Signed-off-by: Miquel Sabaté Solà mikisabate@gmail.com Reviewed-by: Sudeep Holla sudeep.holla@arm.com Reviewed-by: Sunil V L sunilvl@ventanamicro.com Reviewed-by: Alexandre Ghiti alexghiti@rivosinc.com Fixes: 604f32ea6909 ("riscv: cacheinfo: initialize cacheinfo's level and type from ACPI PPTT") Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240913080053.36636-1-mikisabate@gmail.com Signed-off-by: Palmer Dabbelt palmer@rivosinc.com Stable-dep-of: fb8179ce2996 ("riscv: cacheinfo: Use of_property_present() for non-boolean properties") Signed-off-by: Sasha Levin sashal@kernel.org --- arch/riscv/kernel/cacheinfo.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/arch/riscv/kernel/cacheinfo.c b/arch/riscv/kernel/cacheinfo.c index d6c108c50cba9..d32dfdba083e1 100644 --- a/arch/riscv/kernel/cacheinfo.c +++ b/arch/riscv/kernel/cacheinfo.c @@ -75,8 +75,7 @@ int populate_cache_leaves(unsigned int cpu) { struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu); struct cacheinfo *this_leaf = this_cpu_ci->info_list; - struct device_node *np = of_cpu_device_node_get(cpu); - struct device_node *prev = NULL; + struct device_node *np, *prev; int levels = 1, level = 1;
if (!acpi_disabled) { @@ -100,6 +99,10 @@ int populate_cache_leaves(unsigned int cpu) return 0; }
+ np = of_cpu_device_node_get(cpu); + if (!np) + return -ENOENT; + if (of_property_read_bool(np, "cache-size")) ci_leaf_init(this_leaf++, CACHE_TYPE_UNIFIED, level); if (of_property_read_bool(np, "i-cache-size"))