From: Sasha Levin Date: Sat, 23 Dec 2023 16:04:07 +0000 (-0500) Subject: Fixes for 4.19 X-Git-Tag: v6.1.70~43^2~14 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=320086050dab1cb71935cf27a05dc62cf20c408e;p=thirdparty%2Fkernel%2Fstable-queue.git Fixes for 4.19 Signed-off-by: Sasha Levin --- diff --git a/queue-4.19/pinctrl-at91-pio4-use-dedicated-lock-class-for-irq.patch b/queue-4.19/pinctrl-at91-pio4-use-dedicated-lock-class-for-irq.patch new file mode 100644 index 00000000000..ef85a0e4ce4 --- /dev/null +++ b/queue-4.19/pinctrl-at91-pio4-use-dedicated-lock-class-for-irq.patch @@ -0,0 +1,121 @@ +From 80feea56fdb8c266c3c3c3270f6e7f7ce78c8bda Mon Sep 17 00:00:00 2001 +From: Sasha Levin +Date: Fri, 15 Dec 2023 22:34:24 +0100 +Subject: pinctrl: at91-pio4: use dedicated lock class for IRQ +MIME-Version: 1.0 +Content-Type: text/plain; charset=UTF-8 +Content-Transfer-Encoding: 8bit + +From: Alexis Lothoré + +[ Upstream commit 14694179e561b5f2f7e56a0f590e2cb49a9cc7ab ] + +Trying to suspend to RAM on SAMA5D27 EVK leads to the following lockdep +warning: + + ============================================ + WARNING: possible recursive locking detected + 6.7.0-rc5-wt+ #532 Not tainted + -------------------------------------------- + sh/92 is trying to acquire lock: + c3cf306c (&irq_desc_lock_class){-.-.}-{2:2}, at: __irq_get_desc_lock+0xe8/0x100 + + but task is already holding lock: + c3d7c46c (&irq_desc_lock_class){-.-.}-{2:2}, at: __irq_get_desc_lock+0xe8/0x100 + + other info that might help us debug this: + Possible unsafe locking scenario: + + CPU0 + ---- + lock(&irq_desc_lock_class); + lock(&irq_desc_lock_class); + + *** DEADLOCK *** + + May be due to missing lock nesting notation + + 6 locks held by sh/92: + #0: c3aa0258 (sb_writers#6){.+.+}-{0:0}, at: ksys_write+0xd8/0x178 + #1: c4c2df44 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x138/0x284 + #2: c32684a0 (kn->active){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x148/0x284 + #3: c232b6d4 (system_transition_mutex){+.+.}-{3:3}, at: pm_suspend+0x13c/0x4e8 + #4: c387b088 (&dev->mutex){....}-{3:3}, at: __device_suspend+0x1e8/0x91c + #5: c3d7c46c (&irq_desc_lock_class){-.-.}-{2:2}, at: __irq_get_desc_lock+0xe8/0x100 + + stack backtrace: + CPU: 0 PID: 92 Comm: sh Not tainted 6.7.0-rc5-wt+ #532 + Hardware name: Atmel SAMA5 + unwind_backtrace from show_stack+0x18/0x1c + show_stack from dump_stack_lvl+0x34/0x48 + dump_stack_lvl from __lock_acquire+0x19ec/0x3a0c + __lock_acquire from lock_acquire.part.0+0x124/0x2d0 + lock_acquire.part.0 from _raw_spin_lock_irqsave+0x5c/0x78 + _raw_spin_lock_irqsave from __irq_get_desc_lock+0xe8/0x100 + __irq_get_desc_lock from irq_set_irq_wake+0xa8/0x204 + irq_set_irq_wake from atmel_gpio_irq_set_wake+0x58/0xb4 + atmel_gpio_irq_set_wake from irq_set_irq_wake+0x100/0x204 + irq_set_irq_wake from gpio_keys_suspend+0xec/0x2b8 + gpio_keys_suspend from dpm_run_callback+0xe4/0x248 + dpm_run_callback from __device_suspend+0x234/0x91c + __device_suspend from dpm_suspend+0x224/0x43c + dpm_suspend from dpm_suspend_start+0x9c/0xa8 + dpm_suspend_start from suspend_devices_and_enter+0x1e0/0xa84 + suspend_devices_and_enter from pm_suspend+0x460/0x4e8 + pm_suspend from state_store+0x78/0xe4 + state_store from kernfs_fop_write_iter+0x1a0/0x284 + kernfs_fop_write_iter from vfs_write+0x38c/0x6f4 + vfs_write from ksys_write+0xd8/0x178 + ksys_write from ret_fast_syscall+0x0/0x1c + Exception stack(0xc52b3fa8 to 0xc52b3ff0) + 3fa0: 00000004 005a0ae8 00000001 005a0ae8 00000004 00000001 + 3fc0: 00000004 005a0ae8 00000001 00000004 00000004 b6c616c0 00000020 0059d190 + 3fe0: 00000004 b6c61678 aec5a041 aebf1a26 + +This warning is raised because pinctrl-at91-pio4 uses chained IRQ. Whenever +a wake up source configures an IRQ through irq_set_irq_wake, it will +lock the corresponding IRQ desc, and then call irq_set_irq_wake on "parent" +IRQ which will do the same on its own IRQ desc, but since those two locks +share the same class, lockdep reports this as an issue. + +Fix lockdep false positive by setting a different class for parent and +children IRQ + +Fixes: 776180848b57 ("pinctrl: introduce driver for Atmel PIO4 controller") +Signed-off-by: Alexis Lothoré +Link: https://lore.kernel.org/r/20231215-lockdep_warning-v1-1-8137b2510ed5@bootlin.com +Signed-off-by: Linus Walleij +Signed-off-by: Sasha Levin +--- + drivers/pinctrl/pinctrl-at91-pio4.c | 8 ++++++++ + 1 file changed, 8 insertions(+) + +diff --git a/drivers/pinctrl/pinctrl-at91-pio4.c b/drivers/pinctrl/pinctrl-at91-pio4.c +index cbbda24bf6a80..67befdce3805b 100644 +--- a/drivers/pinctrl/pinctrl-at91-pio4.c ++++ b/drivers/pinctrl/pinctrl-at91-pio4.c +@@ -939,6 +939,13 @@ static const struct of_device_id atmel_pctrl_of_match[] = { + } + }; + ++/* ++ * This lock class allows to tell lockdep that parent IRQ and children IRQ do ++ * not share the same class so it does not raise false positive ++ */ ++static struct lock_class_key atmel_lock_key; ++static struct lock_class_key atmel_request_key; ++ + static int atmel_pinctrl_probe(struct platform_device *pdev) + { + struct device *dev = &pdev->dev; +@@ -1089,6 +1096,7 @@ static int atmel_pinctrl_probe(struct platform_device *pdev) + irq_set_chip_and_handler(irq, &atmel_gpio_irq_chip, + handle_simple_irq); + irq_set_chip_data(irq, atmel_pioctrl); ++ irq_set_lockdep_class(irq, &atmel_lock_key, &atmel_request_key); + dev_dbg(dev, + "atmel gpio irq domain: hwirq: %d, linux irq: %d\n", + i, irq); +-- +2.43.0 + diff --git a/queue-4.19/series b/queue-4.19/series index 0b161b05469..60dcb6771ca 100644 --- a/queue-4.19/series +++ b/queue-4.19/series @@ -16,3 +16,4 @@ net-check-vlan-filter-feature-in-vlan_vids_add_by_de.patch afs-fix-the-dynamic-root-s-d_delete-to-always-delete.patch net-warn-if-gso_type-isn-t-set-for-a-gso-skb.patch net-check-dev-gso_max_size-in-gso_features_check.patch +pinctrl-at91-pio4-use-dedicated-lock-class-for-irq.patch