From: Vladimir Oltean <vladimir.oltean@nxp.com> To: linux-arm-kernel@lists.infradead.org Cc: "Andrew Lunn" <andrew@lunn.ch>, "Gregory Clement" <gregory.clement@bootlin.com>, "Sebastian Hesselbarth" <sebastian.hesselbarth@gmail.com>, "Linus Walleij" <linus.walleij@linaro.org>, linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, "Marek Behún" <kabel@kernel.org>, "Pali Rohár" <pali@kernel.org> Subject: [PATCH 2/2] pinctrl: armada-37xx: use raw spinlocks for regmap to avoid invalid wait context Date: Sun, 17 Jul 2022 02:37:45 +0300 [thread overview] Message-ID: <20220716233745.1704677-3-vladimir.oltean@nxp.com> (raw) In-Reply-To: <20220716233745.1704677-1-vladimir.oltean@nxp.com> The irqchip->irq_set_type method is called by __irq_set_trigger() under the desc->lock raw spinlock. The armada-37xx implementation, armada_37xx_irq_set_type(), uses an MMIO regmap created by of_syscon_register(), which uses plain spinlocks (the kind that are sleepable on RT). Therefore, this is an invalid locking scheme for which we get a kernel splat stating just that ("[ BUG: Invalid wait context ]"), because the context in which the plain spinlock may sleep is atomic due to the raw spinlock. We need to go raw spinlocks all the way. Make this driver create its own MMIO regmap, with use_raw_spinlock=true, and stop relying on syscon to provide it. This patch depends on commit 67021f25d952 ("regmap: teach regmap to use raw spinlocks if requested in the config"). Fixes: 2f227605394b ("pinctrl: armada-37xx: Add irqchip support") Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> --- drivers/pinctrl/mvebu/pinctrl-armada-37xx.c | 27 ++++++++++++++++----- 1 file changed, 21 insertions(+), 6 deletions(-) diff --git a/drivers/pinctrl/mvebu/pinctrl-armada-37xx.c b/drivers/pinctrl/mvebu/pinctrl-armada-37xx.c index 8fddc67271b4..bcde042d29dc 100644 --- a/drivers/pinctrl/mvebu/pinctrl-armada-37xx.c +++ b/drivers/pinctrl/mvebu/pinctrl-armada-37xx.c @@ -1107,25 +1107,40 @@ static const struct of_device_id armada_37xx_pinctrl_of_match[] = { { }, }; +static const struct regmap_config armada_37xx_pinctrl_regmap_config = { + .reg_bits = 32, + .val_bits = 32, + .reg_stride = 4, + .use_raw_spinlock = true, +}; + static int __init armada_37xx_pinctrl_probe(struct platform_device *pdev) { struct armada_37xx_pinctrl *info; struct device *dev = &pdev->dev; - struct device_node *np = dev->of_node; struct regmap *regmap; + void __iomem *base; int ret; + base = devm_platform_get_and_ioremap_resource(pdev, 0, NULL); + if (IS_ERR(base)) { + dev_err(dev, "failed to ioremap base address: %pe\n", base); + return PTR_ERR(base); + } + + regmap = devm_regmap_init_mmio(dev, base, + &armada_37xx_pinctrl_regmap_config); + if (IS_ERR(regmap)) { + dev_err(dev, "failed to create regmap: %pe\n", regmap); + return PTR_ERR(regmap); + } + info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL); if (!info) return -ENOMEM; info->dev = dev; - - regmap = syscon_node_to_regmap(np); - if (IS_ERR(regmap)) - return dev_err_probe(dev, PTR_ERR(regmap), "cannot get regmap\n"); info->regmap = regmap; - info->data = of_device_get_match_data(dev); ret = armada_37xx_pinctrl_register(pdev, info); -- 2.34.1
WARNING: multiple messages have this Message-ID (diff)
From: Vladimir Oltean <vladimir.oltean@nxp.com> To: linux-arm-kernel@lists.infradead.org Cc: "Andrew Lunn" <andrew@lunn.ch>, "Gregory Clement" <gregory.clement@bootlin.com>, "Sebastian Hesselbarth" <sebastian.hesselbarth@gmail.com>, "Linus Walleij" <linus.walleij@linaro.org>, linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, "Marek Behún" <kabel@kernel.org>, "Pali Rohár" <pali@kernel.org> Subject: [PATCH 2/2] pinctrl: armada-37xx: use raw spinlocks for regmap to avoid invalid wait context Date: Sun, 17 Jul 2022 02:37:45 +0300 [thread overview] Message-ID: <20220716233745.1704677-3-vladimir.oltean@nxp.com> (raw) In-Reply-To: <20220716233745.1704677-1-vladimir.oltean@nxp.com> The irqchip->irq_set_type method is called by __irq_set_trigger() under the desc->lock raw spinlock. The armada-37xx implementation, armada_37xx_irq_set_type(), uses an MMIO regmap created by of_syscon_register(), which uses plain spinlocks (the kind that are sleepable on RT). Therefore, this is an invalid locking scheme for which we get a kernel splat stating just that ("[ BUG: Invalid wait context ]"), because the context in which the plain spinlock may sleep is atomic due to the raw spinlock. We need to go raw spinlocks all the way. Make this driver create its own MMIO regmap, with use_raw_spinlock=true, and stop relying on syscon to provide it. This patch depends on commit 67021f25d952 ("regmap: teach regmap to use raw spinlocks if requested in the config"). Fixes: 2f227605394b ("pinctrl: armada-37xx: Add irqchip support") Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> --- drivers/pinctrl/mvebu/pinctrl-armada-37xx.c | 27 ++++++++++++++++----- 1 file changed, 21 insertions(+), 6 deletions(-) diff --git a/drivers/pinctrl/mvebu/pinctrl-armada-37xx.c b/drivers/pinctrl/mvebu/pinctrl-armada-37xx.c index 8fddc67271b4..bcde042d29dc 100644 --- a/drivers/pinctrl/mvebu/pinctrl-armada-37xx.c +++ b/drivers/pinctrl/mvebu/pinctrl-armada-37xx.c @@ -1107,25 +1107,40 @@ static const struct of_device_id armada_37xx_pinctrl_of_match[] = { { }, }; +static const struct regmap_config armada_37xx_pinctrl_regmap_config = { + .reg_bits = 32, + .val_bits = 32, + .reg_stride = 4, + .use_raw_spinlock = true, +}; + static int __init armada_37xx_pinctrl_probe(struct platform_device *pdev) { struct armada_37xx_pinctrl *info; struct device *dev = &pdev->dev; - struct device_node *np = dev->of_node; struct regmap *regmap; + void __iomem *base; int ret; + base = devm_platform_get_and_ioremap_resource(pdev, 0, NULL); + if (IS_ERR(base)) { + dev_err(dev, "failed to ioremap base address: %pe\n", base); + return PTR_ERR(base); + } + + regmap = devm_regmap_init_mmio(dev, base, + &armada_37xx_pinctrl_regmap_config); + if (IS_ERR(regmap)) { + dev_err(dev, "failed to create regmap: %pe\n", regmap); + return PTR_ERR(regmap); + } + info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL); if (!info) return -ENOMEM; info->dev = dev; - - regmap = syscon_node_to_regmap(np); - if (IS_ERR(regmap)) - return dev_err_probe(dev, PTR_ERR(regmap), "cannot get regmap\n"); info->regmap = regmap; - info->data = of_device_get_match_data(dev); ret = armada_37xx_pinctrl_register(pdev, info); -- 2.34.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2022-07-16 23:38 UTC|newest] Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top 2022-07-16 23:37 [PATCH 0/2] Fix kernel splats on boot with armada-37xx irqchip driver Vladimir Oltean 2022-07-16 23:37 ` Vladimir Oltean 2022-07-16 23:37 ` [PATCH 1/2] pinctrl: armada-37xx: make irq_lock a raw spinlock to avoid invalid wait context Vladimir Oltean 2022-07-16 23:37 ` Vladimir Oltean 2022-07-16 23:37 ` Vladimir Oltean [this message] 2022-07-16 23:37 ` [PATCH 2/2] pinctrl: armada-37xx: use raw spinlocks for regmap " Vladimir Oltean 2022-07-18 13:43 ` [PATCH 0/2] Fix kernel splats on boot with armada-37xx irqchip driver Linus Walleij 2022-07-18 13:43 ` Linus Walleij 2022-07-18 14:06 ` Vladimir Oltean 2022-07-18 14:06 ` Vladimir Oltean
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20220716233745.1704677-3-vladimir.oltean@nxp.com \ --to=vladimir.oltean@nxp.com \ --cc=andrew@lunn.ch \ --cc=gregory.clement@bootlin.com \ --cc=kabel@kernel.org \ --cc=linus.walleij@linaro.org \ --cc=linux-arm-kernel@lists.infradead.org \ --cc=linux-gpio@vger.kernel.org \ --cc=linux-kernel@vger.kernel.org \ --cc=pali@kernel.org \ --cc=sebastian.hesselbarth@gmail.com \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.