From 37d401c9c4b89c3c193726e177493ef06c657f40 Mon Sep 17 00:00:00 2001 From: Gou Hao Date: Mon, 27 Jul 2026 18:42:14 +0800 Subject: [PATCH] powerpc/xive: defer setting cause_ipi until IPI init succeeds MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit xive_smp_probe() currently assigns smp_ops->cause_ipi = xive_cause_ipi before calling xive_init_ipis() and xive_setup_cpu_ipi(). If either call fails, the platform probe handler returns early but cause_ipi remains pointing to xive_cause_ipi -- which accesses per-cpu IPI data (xc->ipi_data) that was never properly initialized, leading to a WARN and a crash. Move the cause_ipi assignment to after both calls succeed, so that smp_ops->cause_ipi is only set when the IPI subsystem is fully initialized. Signed-off-by: Gou Hao Suggested-by: Cédric Le Goater Reviewed-by: jiazhenyuan Reviewed-by: Cédric Le Goater Signed-off-by: Madhavan Srinivasan Link: https://patch.msgid.link/20260727104215.184786-5-gouhao@uniontech.com --- arch/powerpc/sysdev/xive/common.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/sysdev/xive/common.c b/arch/powerpc/sysdev/xive/common.c index bbe7c85274ea..8ae088632337 100644 --- a/arch/powerpc/sysdev/xive/common.c +++ b/arch/powerpc/sysdev/xive/common.c @@ -1269,15 +1269,19 @@ int __init xive_smp_probe(void) { int ret; - smp_ops->cause_ipi = xive_cause_ipi; - /* Register the IPI */ ret = xive_init_ipis(); if (ret < 0) return ret; /* Allocate and setup IPI for the boot CPU */ - return xive_setup_cpu_ipi(smp_processor_id()); + ret = xive_setup_cpu_ipi(smp_processor_id()); + if (ret < 0) + return ret; + + smp_ops->cause_ipi = xive_cause_ipi; + + return 0; } #endif /* CONFIG_SMP */