Greetings, Commit 481c2d14627d ("tpm,tpm_tis: Disable interrupts after 1000 unhandled IRQs") introduced a kernel warning for boards that do not have a TPM loaded but have one defined in the device-tree (ie a subloaded board assembly): [ 2.434431] WARNING: CPU: 3 PID: 55 at kernel/workqueue.c:3397 __flush_work.isra.0+0x2ac/0x2d8 [ 2.443069] Modules linked in: [ 2.446133] CPU: 3 PID: 55 Comm: kworker/u8:3 Not tainted 6.6.8-00021-g232153790aa6-dirty #434 [ 2.454758] Hardware name: Gateworks Venice GW73xx-2x i.MX8MP Development Kit (DT) [ 2.462337] Workqueue: events_unbound async_run_entry_fn [ 2.467669] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 2.474647] pc : __flush_work.isra.0+0x2ac/0x2d8 [ 2.479278] lr : flush_work+0x10/0x1c [ 2.482950] sp : ffff80008270ba40 [ 2.486271] x29: ffff80008270ba40 x28: 00000000ffffffff x27: 00000000ffffffff [ 2.493425] x26: ffff000000293000 x25: ffff80008218aff8 x24: ffff800080a1c6a8 [ 2.500578] x23: 00000000ffffffff x22: ffff80008213ca18 x21: 0000000000000001 [ 2.507731] x20: ffff000000e142c0 x19: ffff000000e14280 x18: 0000000000000000 [ 2.514884] x17: 0000000000000000 x16: 000000000000001c x15: 0000000000000000 [ 2.522038] x14: ffff00003fd94100 x13: 0000000000000002 x12: 0000000000000000 [ 2.529191] x11: 0000000000000400 x10: 0000000000000910 x9 : 00000000ffffffff [ 2.536346] x8 : 0000000000000cc1 x7 : ffff8000804c76d8 x6 : 00000000090ee8ad [ 2.543500] x5 : ffff00000026c380 x4 : 0000000000000000 x3 : 0000000000000000 [ 2.550655] x2 : 0000000000000000 x1 : ffff00000026c380 x0 : 0000000000000000 [ 2.557806] Call trace: [ 2.560261] __flush_work.isra.0+0x2ac/0x2d8 [ 2.564544] flush_work+0x10/0x1c [ 2.567869] tpm_tis_remove+0x8c/0xc4 [ 2.571545] tpm_tis_core_init+0x194/0x7b8 [ 2.575656] tpm_tis_spi_probe+0xa4/0xd4 [ 2.579593] tpm_tis_spi_driver_probe+0x34/0x64 [ 2.584136] spi_probe+0x84/0xe4 [ 2.587377] really_probe+0x148/0x2c0 [ 2.591052] __driver_probe_device+0x78/0x12c [ 2.595417] driver_probe_device+0xd8/0x15c [ 2.599609] __device_attach_driver+0xb8/0x134 [ 2.604064] bus_for_each_drv+0x84/0xe0 [ 2.607913] __device_attach_async_helper+0xac/0xd0 [ 2.612808] async_run_entry_fn+0x34/0xe0 [ 2.616832] process_one_work+0x138/0x260 [ 2.620851] worker_thread+0x32c/0x438 [ 2.624609] kthread+0x118/0x11c [ 2.627844] ret_from_fork+0x10/0x20 [ 2.631428] ---[ end trace 0000000000000000 ]--- The issue is caused by tpm_tis_remove() calling flush_work() on the work queue that has not yet been initialized. I can move the INIT_WORK call added in this commit into the probe to fix this: diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c index d5ea22196b5b..e62294b3a437 100644 --- a/drivers/char/tpm/tpm_tis_core.c +++ b/drivers/char/tpm/tpm_tis_core.c @@ -1133,6 +1133,8 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq, dev_set_drvdata(&chip->dev, priv); + INIT_WORK(&priv->free_irq_work, tpm_tis_free_irq_func); + rc = tpm_tis_read32(priv, TPM_DID_VID(0), &vendor); if (rc < 0) return rc; @@ -1159,8 +1161,6 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq, } } - INIT_WORK(&priv->free_irq_work, tpm_tis_free_irq_func); - if (chip->ops->clk_enable != NULL) chip->ops->clk_enable(chip, true); However I wonder if we should simply have error checking for an invalid vendor of 0xffffffff. Is there any reason to not return an -ENODEV if vendor == 0xffffffff? diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c index d5ea22196b5b..1bb1b3e1b2d0 100644 --- a/drivers/char/tpm/tpm_tis_core.c +++ b/drivers/char/tpm/tpm_tis_core.c @@ -1136,6 +1136,8 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq, rc = tpm_tis_read32(priv, TPM_DID_VID(0), &vendor); if (rc < 0) return rc; + if (rc == 0xffffffff) + return -ENODEV; priv->manufacturer_id = vendor; I'm not sure if a hard coded 0xffffffff check is best here. Best regards, Tim