From 29be646f75c4406bdd8322572a6054ebd22bf63b Mon Sep 17 00:00:00 2001 From: Sebastian Reichel Date: Wed, 19 Nov 2025 01:41:40 +0100 Subject: [PATCH] platform: arm64: thinkpad-t14s-ec: fix IRQ race condition MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Fix a race condition, that an input key related interrupt might be triggered before the input handler has been registered, which results in a NULL pointer dereference. This can happen if the user enables the keyboard backlight shortly before the driver is being probed. This fixes the following backtrace visible in dmesg: Unable to handle kernel NULL pointer dereference at virtual address 00000000000000e0 ... Call trace: sparse_keymap_report_event+0x2c/0x978 [sparse_keymap] (P) t14s_ec_irq_handler+0x190/0x3e8 [lenovo_thinkpad_t14s] irq_thread_fn+0x30/0xb8 irq_thread+0x18c/0x3b0 kthread+0x148/0x228 ret_from_fork+0x10/0x20 Fixes: 60b7ab6ce030 ("platform: arm64: thinkpad-t14s-ec: new driver") Signed-off-by: Sebastian Reichel Reviewed-by: Bryan O'Donoghue Link: https://patch.msgid.link/20251119-thinkpad-t14s-ec-improvements-v2-1-441219857c02@kernel.org Reviewed-by: Ilpo Järvinen Signed-off-by: Ilpo Järvinen --- drivers/platform/arm64/lenovo-thinkpad-t14s.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/platform/arm64/lenovo-thinkpad-t14s.c b/drivers/platform/arm64/lenovo-thinkpad-t14s.c index 1d5d11adaf32..c1c01b977f2b 100644 --- a/drivers/platform/arm64/lenovo-thinkpad-t14s.c +++ b/drivers/platform/arm64/lenovo-thinkpad-t14s.c @@ -557,12 +557,6 @@ static int t14s_ec_probe(struct i2c_client *client) return dev_err_probe(dev, PTR_ERR(ec->regmap), "Failed to init regmap\n"); - ret = devm_request_threaded_irq(dev, client->irq, NULL, - t14s_ec_irq_handler, - IRQF_ONESHOT, dev_name(dev), ec); - if (ret < 0) - return dev_err_probe(dev, ret, "Failed to get IRQ\n"); - ret = t14s_leds_probe(ec); if (ret < 0) return ret; @@ -579,6 +573,12 @@ static int t14s_ec_probe(struct i2c_client *client) if (ret < 0) return ret; + ret = devm_request_threaded_irq(dev, client->irq, NULL, + t14s_ec_irq_handler, + IRQF_ONESHOT, dev_name(dev), ec); + if (ret < 0) + return dev_err_probe(dev, ret, "Failed to get IRQ\n"); + /* * Disable wakeup support by default, because the driver currently does * not support masking any events and the laptop should not wake up when -- 2.47.3