6.16-stable review patch. If anyone has any objections, please let me know.
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From: Arnd Bergmann arnd@arndb.de
[ Upstream commit adc353c0bfb243ebfd29b6222fa3bf149169a6de ]
A CPU mask on the stack is broken for large values of CONFIG_NR_CPUS:
kernel/trace/preemptirq_delay_test.c: In function ‘preemptirq_delay_run’: kernel/trace/preemptirq_delay_test.c:143:1: error: the frame size of 8512 bytes is larger than 1536 bytes [-Werror=frame-larger-than=]
Fall back to dynamic allocation here.
Cc: Masami Hiramatsu mhiramat@kernel.org Cc: Song Chen chensong_2000@189.cn Cc: Mathieu Desnoyers mathieu.desnoyers@efficios.com Link: https://lore.kernel.org/20250620111215.3365305-1-arnd@kernel.org Fixes: 4b9091e1c194 ("kernel: trace: preemptirq_delay_test: add cpu affinity") Signed-off-by: Arnd Bergmann arnd@arndb.de Signed-off-by: Steven Rostedt (Google) rostedt@goodmis.org Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/trace/preemptirq_delay_test.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-)
diff --git a/kernel/trace/preemptirq_delay_test.c b/kernel/trace/preemptirq_delay_test.c index 314ffc143039..acb0c971a408 100644 --- a/kernel/trace/preemptirq_delay_test.c +++ b/kernel/trace/preemptirq_delay_test.c @@ -117,12 +117,15 @@ static int preemptirq_delay_run(void *data) { int i; int s = MIN(burst_size, NR_TEST_FUNCS); - struct cpumask cpu_mask; + cpumask_var_t cpu_mask; + + if (!alloc_cpumask_var(&cpu_mask, GFP_KERNEL)) + return -ENOMEM;
if (cpu_affinity > -1) { - cpumask_clear(&cpu_mask); - cpumask_set_cpu(cpu_affinity, &cpu_mask); - if (set_cpus_allowed_ptr(current, &cpu_mask)) + cpumask_clear(cpu_mask); + cpumask_set_cpu(cpu_affinity, cpu_mask); + if (set_cpus_allowed_ptr(current, cpu_mask)) pr_err("cpu_affinity:%d, failed\n", cpu_affinity); }
@@ -139,6 +142,8 @@ static int preemptirq_delay_run(void *data)
__set_current_state(TASK_RUNNING);
+ free_cpumask_var(cpu_mask); + return 0; }