From: Yun Zhou Date: Mon, 22 Jun 2026 07:43:50 +0000 (+0800) Subject: net: mvneta: re-enable percpu interrupt on resume X-Git-Tag: v7.2-rc1~29^2~26 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=fd398d6480987e4c84fff0aaab6b9d6642a93343;p=thirdparty%2Flinux.git net: mvneta: re-enable percpu interrupt on resume On Marvell MPIC platforms (Armada 370/XP/38x), mvneta uses a percpu IRQ disable/enable scheme for NAPI: the ISR (mvneta_percpu_isr) calls disable_percpu_irq() to mask the MPIC per-CPU interrupt and schedules NAPI poll, which calls enable_percpu_irq() on completion to unmask. If suspend occurs while NAPI poll is pending (between disable_percpu_irq in the ISR and enable_percpu_irq in poll completion), the interrupt is never re-enabled: 1. mvneta_percpu_isr: disable_percpu_irq() + napi_schedule() => MPIC masked, percpu_enabled cpumask bit cleared 2. NAPI poll does not complete before suspend proceeds (on PREEMPT_RT this is highly likely since softirqs run in ksoftirqd which gets frozen; on non-RT it can happen when softirq processing is deferred to ksoftirqd) 3. mvneta_stop_dev => napi_disable(): cancels the pending poll without executing the completion path 4. suspend_device_irqs => IRQCHIP_MASK_ON_SUSPEND: masks MPIC (already masked, but records IRQS_SUSPENDED) 5. Resume: mpic_resume checks irq_percpu_is_enabled() => false (bit was cleared in step 1) => skips unmask 6. mvneta_start_dev only restores device-level INTR_NEW_MASK, does not touch the MPIC per-CPU mask Result: MPIC per-CPU interrupt stays masked permanently. The NIC generates interrupts (INTR_NEW_CAUSE != 0) but the CPU never receives them, causing complete loss of network connectivity. Fix by calling on_each_cpu(mvneta_percpu_enable) in the resume path to unconditionally unmask the MPIC per-CPU interrupt regardless of pre-suspend state. Fixes: 12bb03b436da ("net: mvneta: Handle per-cpu interrupts") Signed-off-by: Yun Zhou Reviewed-by: Sebastian Andrzej Siewior Link: https://patch.msgid.link/20260622074350.1666290-1-yun.zhou@windriver.com Signed-off-by: Jakub Kicinski --- diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c index 0c061fb0ed072..744d6585a949d 100644 --- a/drivers/net/ethernet/marvell/mvneta.c +++ b/drivers/net/ethernet/marvell/mvneta.c @@ -5900,6 +5900,9 @@ static int mvneta_resume(struct device *device) rtnl_unlock(); mvneta_set_rx_mode(dev); + if (!pp->neta_armada3700) + on_each_cpu(mvneta_percpu_enable, pp, true); + return 0; } #endif