From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5E15C3B47E3; Tue, 21 Jul 2026 22:28:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784672930; cv=none; b=je4WQ0M8IQkS+XSFZz8TYRp5U6rIYhVwAnfwqlbVlkk8NtkoSyP7pHKk0EQIstNbbPQKCG7+zTAqBzPPr1VuAKlnfD0AAWn/dV3DVoVuDY+aMsP0mrRZpXK32lCgvRIA62KHzqR6nnFeaIzboSMLaKFNfn0ko1Hr2XvPFHgi0Tc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784672930; c=relaxed/simple; bh=jhElBNk5tw97JVV5fc4Adk04DsUlPudZGP5mZAUSVAA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ScNhL62vdTM21LCxmu/La96MhYffkpRrKiPcAC9GRXXmvy+u9Jm5GTE+NA2cjzEP0Dii6qiQ1z11Jsvi76b2e/p9CIgjFydpyRcae+u/B6Vw/+cKypq00GidKw8cwPSXZ3V1vodh1YyoT6heVehd/TCMjuKOcdFBqUB+4hxrlJo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=0NLY85rn; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="0NLY85rn" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D79871F00A3E; Tue, 21 Jul 2026 22:28:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784672928; bh=fzqoTsaC/90XhPQKeuQj/ZKSEEt4DSbQfC+YZVwd95c=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=0NLY85rnG7JEoGLA7AV3wGgIzSSv0KzPELhqHdnuaEojnJWsPfSYRVjVGgmwpP1z/ aVh1RoilvIJFgE+lPeQy/HbKswAeXKt27AB0MKvF4+1Q19k8+VimIGULoH3l/Igswz SlwyPjFJEClRyEEL5QroPcYWFklVZrn5TrxyLCP4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Runyu Xiao , Sebastian Andrzej Siewior , Andy Shevchenko , Bartosz Golaszewski , Sasha Levin Subject: [PATCH 5.15 773/843] gpio: sch: use raw_spinlock_t in the irq startup path Date: Tue, 21 Jul 2026 17:26:48 +0200 Message-ID: <20260721152423.444822376@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260721152405.946368001@linuxfoundation.org> References: <20260721152405.946368001@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Runyu Xiao [ Upstream commit 286533cb14a3c8a8bd39ff64ea2fc8e1aa0f638b ] sch_irq_unmask() enables the GPIO IRQ and then updates the controller state through sch_irq_mask_unmask(), which takes sch->lock with spin_lock_irqsave(). The callback can be reached from irq_startup() while setting up a requested IRQ. That path is not sleepable, but on PREEMPT_RT a regular spinlock_t becomes a sleeping lock. This issue was found by our static analysis tool and then manually reviewed against the current tree. The grounded PoC kept the request_threaded_irq() -> __setup_irq() -> irq_startup() -> sch_irq_unmask() -> sch_irq_mask_unmask() carrier and used the original spin_lock_irqsave(&sch->lock) edge. Lockdep reported: BUG: sleeping function called from invalid context hardirqs last disabled at ... __setup_irq.constprop.0 ... [vuln_msv] sch_rt_spin_lock_irqsave+0x1c/0x30 [vuln_msv] sch_irq_mask_unmask.constprop.0+0x31/0x70 [vuln_msv] __setup_irq.constprop.0+0xd/0x30 [vuln_msv] Convert the SCH controller lock to raw_spinlock_t. The same lock is also used by the GPIO direction and value callbacks, but those critical sections only update MMIO-backed GPIO registers and do not contain sleepable operations. Keeping this register lock non-sleeping is therefore appropriate for the irqchip callbacks and does not change the GPIO-side locking contract. Fixes: 7a81638485c1 ("gpio: sch: Add edge event support") Cc: stable@vger.kernel.org Signed-off-by: Runyu Xiao Reviewed-by: Sebastian Andrzej Siewior Reviewed-by: Andy Shevchenko Link: https://patch.msgid.link/20260617154035.1199948-2-runyu.xiao@seu.edu.cn Signed-off-by: Bartosz Golaszewski Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/gpio/gpio-sch.c | 41 ++++++++++++++++++++--------------------- 1 file changed, 20 insertions(+), 21 deletions(-) --- a/drivers/gpio/gpio-sch.c +++ b/drivers/gpio/gpio-sch.c @@ -39,7 +39,7 @@ struct sch_gpio { struct gpio_chip chip; struct irq_chip irqchip; - spinlock_t lock; + raw_spinlock_t lock; unsigned short iobase; unsigned short resume_base; @@ -103,9 +103,9 @@ static int sch_gpio_direction_in(struct struct sch_gpio *sch = gpiochip_get_data(gc); unsigned long flags; - spin_lock_irqsave(&sch->lock, flags); + raw_spin_lock_irqsave(&sch->lock, flags); sch_gpio_reg_set(sch, gpio_num, GIO, 1); - spin_unlock_irqrestore(&sch->lock, flags); + raw_spin_unlock_irqrestore(&sch->lock, flags); return 0; } @@ -116,16 +116,14 @@ static int sch_gpio_get(struct gpio_chip return sch_gpio_reg_get(sch, gpio_num, GLV); } -static int sch_gpio_set(struct gpio_chip *gc, unsigned int gpio_num, int val) +static void sch_gpio_set(struct gpio_chip *gc, unsigned int gpio_num, int val) { struct sch_gpio *sch = gpiochip_get_data(gc); unsigned long flags; - spin_lock_irqsave(&sch->lock, flags); + raw_spin_lock_irqsave(&sch->lock, flags); sch_gpio_reg_set(sch, gpio_num, GLV, val); - spin_unlock_irqrestore(&sch->lock, flags); - - return 0; + raw_spin_unlock_irqrestore(&sch->lock, flags); } static int sch_gpio_direction_out(struct gpio_chip *gc, unsigned int gpio_num, @@ -134,9 +132,9 @@ static int sch_gpio_direction_out(struct struct sch_gpio *sch = gpiochip_get_data(gc); unsigned long flags; - spin_lock_irqsave(&sch->lock, flags); + raw_spin_lock_irqsave(&sch->lock, flags); sch_gpio_reg_set(sch, gpio_num, GIO, 0); - spin_unlock_irqrestore(&sch->lock, flags); + raw_spin_unlock_irqrestore(&sch->lock, flags); /* * according to the datasheet, writing to the level register has no @@ -147,7 +145,8 @@ static int sch_gpio_direction_out(struct * But we cannot prevent a short low pulse if direction is set to high * and an external pull-up is connected. */ - return sch_gpio_set(gc, gpio_num, val); + sch_gpio_set(gc, gpio_num, val); + return 0; } static int sch_gpio_get_direction(struct gpio_chip *gc, unsigned int gpio_num) @@ -166,7 +165,7 @@ static const struct gpio_chip sch_gpio_c .direction_input = sch_gpio_direction_in, .get = sch_gpio_get, .direction_output = sch_gpio_direction_out, - .set_rv = sch_gpio_set, + .set = sch_gpio_set, .get_direction = sch_gpio_get_direction, }; @@ -195,14 +194,14 @@ static int sch_irq_type(struct irq_data return -EINVAL; } - spin_lock_irqsave(&sch->lock, flags); + raw_spin_lock_irqsave(&sch->lock, flags); sch_gpio_reg_set(sch, gpio_num, GTPE, rising); sch_gpio_reg_set(sch, gpio_num, GTNE, falling); irq_set_handler_locked(d, handle_edge_irq); - spin_unlock_irqrestore(&sch->lock, flags); + raw_spin_unlock_irqrestore(&sch->lock, flags); return 0; } @@ -214,9 +213,9 @@ static void sch_irq_ack(struct irq_data irq_hw_number_t gpio_num = irqd_to_hwirq(d); unsigned long flags; - spin_lock_irqsave(&sch->lock, flags); + raw_spin_lock_irqsave(&sch->lock, flags); sch_gpio_reg_set(sch, gpio_num, GTS, 1); - spin_unlock_irqrestore(&sch->lock, flags); + raw_spin_unlock_irqrestore(&sch->lock, flags); } static void sch_irq_mask_unmask(struct irq_data *d, int val) @@ -226,9 +225,9 @@ static void sch_irq_mask_unmask(struct i irq_hw_number_t gpio_num = irqd_to_hwirq(d); unsigned long flags; - spin_lock_irqsave(&sch->lock, flags); + raw_spin_lock_irqsave(&sch->lock, flags); sch_gpio_reg_set(sch, gpio_num, GGPE, val); - spin_unlock_irqrestore(&sch->lock, flags); + raw_spin_unlock_irqrestore(&sch->lock, flags); } static void sch_irq_mask(struct irq_data *d) @@ -251,12 +250,12 @@ static u32 sch_gpio_gpe_handler(acpi_han int offset; u32 ret; - spin_lock_irqsave(&sch->lock, flags); + raw_spin_lock_irqsave(&sch->lock, flags); core_status = inl(sch->iobase + CORE_BANK_OFFSET + GTS); resume_status = inl(sch->iobase + RESUME_BANK_OFFSET + GTS); - spin_unlock_irqrestore(&sch->lock, flags); + raw_spin_unlock_irqrestore(&sch->lock, flags); pending = (resume_status << sch->resume_base) | core_status; for_each_set_bit(offset, &pending, sch->chip.ngpio) @@ -322,7 +321,7 @@ static int sch_gpio_probe(struct platfor pdev->name)) return -EBUSY; - spin_lock_init(&sch->lock); + raw_spin_lock_init(&sch->lock); sch->iobase = res->start; sch->chip = sch_gpio_chip; sch->chip.label = dev_name(&pdev->dev);