The branch stable/14 has been updated by kbowling: URL: https://cgit.FreeBSD.org/src/commit/?id=c287fb614943a721adc0ef59a7e19c32b839e5d9
commit c287fb614943a721adc0ef59a7e19c32b839e5d9 Author: Kevin Bowling <[email protected]> AuthorDate: 2026-08-12 00:12:15 +0000 Commit: Kevin Bowling <[email protected]> CommitDate: 2026-08-26 00:26:07 +0000 iflib: Defer LED control to the device taskqueue led(4) invokes driver callbacks while holding its mutex, including from a callout. iflib_led_func() cannot acquire the sleepable context lock in those contexts without causing a lock-order reversal or sleeping from the callout. Record the latest requested state under the iflib state lock and enqueue the existing per-device taskqueue. The task can safely take the context lock before invoking the driver. Coalescing requests also avoids accumulating stale blink transitions when hardware access is slow. Destroy the LED device before draining its task so no new callback can race driver detach. (cherry picked from commit 952994751911d5d059d53e73eb874e00ee98b9ed) --- sys/net/iflib.c | 35 ++++++++++++++++++++++++++++++++--- 1 file changed, 32 insertions(+), 3 deletions(-) diff --git a/sys/net/iflib.c b/sys/net/iflib.c index f9e98dbbc1c7..87fc5254ef0c 100644 --- a/sys/net/iflib.c +++ b/sys/net/iflib.c @@ -175,10 +175,12 @@ struct iflib_ctx { int ifc_link_state; int ifc_watchdog_events; struct cdev *ifc_led_dev; + int ifc_led_state; struct resource *ifc_msix_mem; struct if_irq ifc_legacy_irq; struct task ifc_admin_task; + struct task ifc_led_task; struct task ifc_vflr_task; struct taskqueue *ifc_tq; struct iflib_filter_info ifc_filter_info; @@ -4669,15 +4671,39 @@ iflib_vlan_unregister(void *arg, if_t ifp, uint16_t vtag) } static void -iflib_led_func(void *arg, int onoff) +_task_fn_led(void *context, int pending __unused) { - if_ctx_t ctx = arg; + if_ctx_t ctx = context; + bool in_detach; + int onoff; + + STATE_LOCK(ctx); + in_detach = (ctx->ifc_flags & IFC_IN_DETACH) != 0; + onoff = ctx->ifc_led_state; + STATE_UNLOCK(ctx); + if (in_detach) + return; CTX_LOCK(ctx); IFDI_LED_FUNC(ctx, onoff); CTX_UNLOCK(ctx); } +static void +iflib_led_func(void *arg, int onoff) +{ + if_ctx_t ctx = arg; + bool in_detach; + + /* led(4) may invoke this callback from a non-sleepable callout. */ + STATE_LOCK(ctx); + ctx->ifc_led_state = onoff; + in_detach = (ctx->ifc_flags & IFC_IN_DETACH) != 0; + STATE_UNLOCK(ctx); + if (!in_detach) + taskqueue_enqueue(ctx->ifc_tq, &ctx->ifc_led_task); +} + /********************************************************************* * * BUS FUNCTION DEFINITIONS @@ -5271,6 +5297,7 @@ iflib_device_register(device_t dev, void *sc, if_shared_ctx_t sctx, if_ctx_t *ct } TASK_INIT(&ctx->ifc_admin_task, 0, _task_fn_admin, ctx); + TASK_INIT(&ctx->ifc_led_task, 0, _task_fn_led, ctx); /* Set up cpu set. If it fails, use the set of all CPUs. */ if (bus_get_cpus(dev, INTR_CPUS, sizeof(ctx->ifc_cpus), &ctx->ifc_cpus) != 0) { @@ -5472,8 +5499,10 @@ iflib_device_deregister(if_ctx_t ctx) CTX_UNLOCK(ctx); iflib_rem_pfil(ctx); - if (ctx->ifc_led_dev != NULL) + if (ctx->ifc_led_dev != NULL) { led_destroy(ctx->ifc_led_dev); + taskqueue_drain(ctx->ifc_tq, &ctx->ifc_led_task); + } iflib_tqg_detach(ctx); iflib_tx_structures_free(ctx);
