The pmsr_lock spinlock used to be necessary to synchronize access to the PMSR register, because that access could have been triggered from either config space access in rcar_pcie_config_access() or an exception handler rcar_pcie_aarch32_abort_handler().
The rcar_pcie_aarch32_abort_handler() case is no longer applicable since commit 6e36203bc14c ("PCI: rcar: Use PCI_SET_ERROR_RESPONSE after read which triggered an exception"), which performs more accurate, controlled invocation of the exception, and a fixup.
This leaves rcar_pcie_config_access() as the only call site from which rcar_pcie_wakeup() is called. The rcar_pcie_config_access() can only be called from the controller struct pci_ops .read and .write callbacks, and those are serialized in drivers/pci/access.c using raw spinlock 'pci_lock' . CONFIG_PCI_LOCKLESS_CONFIG is never set on this platform.
Since the 'pci_lock' is a raw spinlock , and the 'pmsr_lock' is not a raw spinlock, this constellation triggers 'BUG: Invalid wait context' with CONFIG_PROVE_RAW_LOCK_NESTING=y .
Remove the pmsr_lock to fix the locking.
Fixes: a115b1bd3af0 ("PCI: rcar: Add L1 link state fix into data abort hook") Reported-by: Duy Nguyen duy.nguyen.rh@renesas.com Reported-by: Thuan Nguyen thuan.nguyen-hong@banvien.com.vn Cc: stable@vger.kernel.org Signed-off-by: Marek Vasut marek.vasut+renesas@mailbox.org --- ============================= [ BUG: Invalid wait context ] 6.17.0-rc4-next-20250905-00048-ga08e553145e7-dirty #1116 Not tainted ----------------------------- swapper/0/1 is trying to lock: ffffffd92cf69c30 (pmsr_lock){....}-{3:3}, at: rcar_pcie_config_access+0x48/0x260 other info that might help us debug this: context-{5:5} 3 locks held by swapper/0/1: #0: ffffff84c0f890f8 (&dev->mutex){....}-{4:4}, at: device_lock+0x14/0x1c #1: ffffffd92cf675b0 (pci_rescan_remove_lock){+.+.}-{4:4}, at: pci_lock_rescan_remove+0x18/0x20 #2: ffffffd92cf674a0 (pci_lock){....}-{2:2}, at: pci_bus_read_config_dword+0x54/0xd8 stack backtrace: CPU: 3 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.17.0-rc4-next-20250905-00048-ga08e553145e7-dirty #1116 PREEMPT Hardware name: Renesas Salvator-X 2nd version board based on r8a77951 (DT) Call trace: dump_backtrace+0x6c/0x7c (C) show_stack+0x14/0x1c dump_stack_lvl+0x68/0x8c dump_stack+0x14/0x1c __lock_acquire+0x3e8/0x1064 lock_acquire+0x17c/0x2ac _raw_spin_lock_irqsave+0x54/0x70 rcar_pcie_config_access+0x48/0x260 rcar_pcie_read_conf+0x44/0xd8 pci_bus_read_config_dword+0x78/0xd8 pci_bus_generic_read_dev_vendor_id+0x30/0x138 pci_bus_read_dev_vendor_id+0x60/0x68 pci_scan_single_device+0x11c/0x1ec pci_scan_slot+0x7c/0x170 pci_scan_child_bus_extend+0x5c/0x29c pci_scan_child_bus+0x10/0x18 pci_scan_root_bus_bridge+0x90/0xc8 pci_host_probe+0x24/0xc4 rcar_pcie_probe+0x5e8/0x650 platform_probe+0x58/0x88 really_probe+0x190/0x350 __driver_probe_device+0x120/0x138 driver_probe_device+0x38/0xec __driver_attach+0x158/0x168 bus_for_each_dev+0x7c/0xd0 driver_attach+0x20/0x28 bus_add_driver+0xe0/0x1d8 driver_register+0xac/0xe8 __platform_driver_register+0x1c/0x24 rcar_pcie_driver_init+0x18/0x20 do_one_initcall+0xd4/0x220 kernel_init_freeable+0x308/0x30c kernel_init+0x20/0x11c ret_from_fork+0x10/0x20 --- Cc: "Krzysztof Wilczyński" kwilczynski@kernel.org Cc: Bjorn Helgaas bhelgaas@google.com Cc: Geert Uytterhoeven geert+renesas@glider.be Cc: Lorenzo Pieralisi lpieralisi@kernel.org Cc: Magnus Damm magnus.damm@gmail.com Cc: Manivannan Sadhasivam mani@kernel.org Cc: Marc Zyngier maz@kernel.org Cc: Rob Herring robh@kernel.org Cc: Yoshihiro Shimoda yoshihiro.shimoda.uh@renesas.com Cc: linux-pci@vger.kernel.org Cc: linux-renesas-soc@vger.kernel.org --- drivers/pci/controller/pcie-rcar-host.c | 13 ++----------- 1 file changed, 2 insertions(+), 11 deletions(-)
diff --git a/drivers/pci/controller/pcie-rcar-host.c b/drivers/pci/controller/pcie-rcar-host.c index 4780e0109e583..625a00f3b2230 100644 --- a/drivers/pci/controller/pcie-rcar-host.c +++ b/drivers/pci/controller/pcie-rcar-host.c @@ -52,20 +52,13 @@ struct rcar_pcie_host { int (*phy_init_fn)(struct rcar_pcie_host *host); };
-static DEFINE_SPINLOCK(pmsr_lock); - static int rcar_pcie_wakeup(struct device *pcie_dev, void __iomem *pcie_base) { - unsigned long flags; u32 pmsr, val; int ret = 0;
- spin_lock_irqsave(&pmsr_lock, flags); - - if (!pcie_base || pm_runtime_suspended(pcie_dev)) { - ret = -EINVAL; - goto unlock_exit; - } + if (!pcie_base || pm_runtime_suspended(pcie_dev)) + return -EINVAL;
pmsr = readl(pcie_base + PMSR);
@@ -87,8 +80,6 @@ static int rcar_pcie_wakeup(struct device *pcie_dev, void __iomem *pcie_base) writel(L1FAEG | PMEL1RX, pcie_base + PMSR); }
-unlock_exit: - spin_unlock_irqrestore(&pmsr_lock, flags); return ret; }
The rcar_msi_irq_unmask() function may be called from a PCI driver request_threaded_irq() function. This triggers kernel/irq/manage.c __setup_irq() which locks raw spinlock &desc->lock descriptor lock and with that descriptor lock held, calls rcar_msi_irq_unmask().
Since the &desc->lock descriptor lock is a raw spinlock , and the rcar_msi .mask_lock is not a raw spinlock, this setup triggers 'BUG: Invalid wait context' with CONFIG_PROVE_RAW_LOCK_NESTING=y .
Use scoped_guard() to simplify the locking.
Fixes: 83ed8d4fa656 ("PCI: rcar: Convert to MSI domains") Reported-by: Duy Nguyen duy.nguyen.rh@renesas.com Reported-by: Thuan Nguyen thuan.nguyen-hong@banvien.com.vn Cc: stable@vger.kernel.org Signed-off-by: Marek Vasut marek.vasut+renesas@mailbox.org --- ============================= [ BUG: Invalid wait context ] 6.17.0-rc4-next-20250905-00049-g13b74d3367a3-dirty #1117 Not tainted ----------------------------- swapper/0/1 is trying to lock: ffffff84c1974e58 (&msi->mask_lock){....}-{3:3}, at: rcar_msi_irq_unmask+0x28/0x70 other info that might help us debug this: context-{5:5} 6 locks held by swapper/0/1: #0: ffffff84c0e0d0f8 (&dev->mutex){....}-{4:4}, at: device_lock+0x14/0x1c #1: ffffffc0817675b0 (pci_rescan_remove_lock){+.+.}-{4:4}, at: pci_lock_rescan_remove+0x18/0x20 #2: ffffff84c2a691b0 (&dev->mutex){....}-{4:4}, at: device_lock+0x14/0x1c #3: ffffff84c1976108 (&dev->mutex){....}-{4:4}, at: device_lock+0x14/0x1c #4: ffffff84c2a71640 (&desc->request_mutex){+.+.}-{4:4}, at: __setup_irq+0xa4/0x5bc #5: ffffff84c2a714c8 (&irq_desc_lock_class){....}-{2:2}, at: __setup_irq+0x230/0x5bc stack backtrace: CPU: 1 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.17.0-rc4-next-20250905-00049-g13b74d3367a3-dirty #1117 PREEMPT Hardware name: Renesas Salvator-X 2nd version board based on r8a77951 (DT) Call trace: dump_backtrace+0x6c/0x7c (C) show_stack+0x14/0x1c dump_stack_lvl+0x68/0x8c dump_stack+0x14/0x1c __lock_acquire+0x3e8/0x1064 lock_acquire+0x17c/0x2ac _raw_spin_lock_irqsave+0x54/0x70 rcar_msi_irq_unmask+0x28/0x70 irq_chip_unmask_parent+0x18/0x20 cond_startup_parent+0x40/0x44 pci_irq_startup_msi+0x20/0x58 __irq_startup+0x34/0x84 irq_startup+0x64/0x114 __setup_irq+0x3f8/0x5bc request_threaded_irq+0x11c/0x148 pcie_pme_probe+0xec/0x190 pcie_port_probe_service+0x34/0x5c really_probe+0x190/0x350 __driver_probe_device+0x120/0x138 driver_probe_device+0x38/0xec __device_attach_driver+0x100/0x114 bus_for_each_drv+0xa8/0xd0 __device_attach+0xdc/0x15c device_initial_probe+0x10/0x18 bus_probe_device+0x38/0xa0 device_add+0x554/0x68c device_register+0x1c/0x28 pcie_portdrv_probe+0x480/0x518 pci_device_probe+0xcc/0x13c really_probe+0x190/0x350 __driver_probe_device+0x120/0x138 driver_probe_device+0x38/0xec __device_attach_driver+0x100/0x114 bus_for_each_drv+0xa8/0xd0 __device_attach+0xdc/0x15c device_initial_probe+0x10/0x18 pci_bus_add_device+0xb8/0x130 pci_bus_add_devices+0x50/0x74 pci_host_probe+0x90/0xc4 rcar_pcie_probe+0x5e8/0x650 platform_probe+0x58/0x88 really_probe+0x190/0x350 __driver_probe_device+0x120/0x138 driver_probe_device+0x38/0xec __driver_attach+0x158/0x168 bus_for_each_dev+0x7c/0xd0 driver_attach+0x20/0x28 bus_add_driver+0xe0/0x1d8 driver_register+0xac/0xe8 __platform_driver_register+0x1c/0x24 rcar_pcie_driver_init+0x18/0x20 do_one_initcall+0xd4/0x220 kernel_init_freeable+0x308/0x30c kernel_init+0x20/0x11c ret_from_fork+0x10/0x20 --- Cc: "Krzysztof Wilczyński" kwilczynski@kernel.org Cc: Bjorn Helgaas bhelgaas@google.com Cc: Geert Uytterhoeven geert+renesas@glider.be Cc: Lorenzo Pieralisi lpieralisi@kernel.org Cc: Magnus Damm magnus.damm@gmail.com Cc: Manivannan Sadhasivam mani@kernel.org Cc: Marc Zyngier maz@kernel.org Cc: Rob Herring robh@kernel.org Cc: Yoshihiro Shimoda yoshihiro.shimoda.uh@renesas.com Cc: linux-pci@vger.kernel.org Cc: linux-renesas-soc@vger.kernel.org --- drivers/pci/controller/pcie-rcar-host.c | 27 ++++++++++++------------- 1 file changed, 13 insertions(+), 14 deletions(-)
diff --git a/drivers/pci/controller/pcie-rcar-host.c b/drivers/pci/controller/pcie-rcar-host.c index 625a00f3b2230..213028052aa58 100644 --- a/drivers/pci/controller/pcie-rcar-host.c +++ b/drivers/pci/controller/pcie-rcar-host.c @@ -12,6 +12,7 @@ */
#include <linux/bitops.h> +#include <linux/cleanup.h> #include <linux/clk.h> #include <linux/clk-provider.h> #include <linux/delay.h> @@ -38,7 +39,7 @@ struct rcar_msi { DECLARE_BITMAP(used, INT_PCI_MSI_NR); struct irq_domain *domain; struct mutex map_lock; - spinlock_t mask_lock; + raw_spinlock_t mask_lock; int irq1; int irq2; }; @@ -602,28 +603,26 @@ static void rcar_msi_irq_mask(struct irq_data *d) { struct rcar_msi *msi = irq_data_get_irq_chip_data(d); struct rcar_pcie *pcie = &msi_to_host(msi)->pcie; - unsigned long flags; u32 value;
- spin_lock_irqsave(&msi->mask_lock, flags); - value = rcar_pci_read_reg(pcie, PCIEMSIIER); - value &= ~BIT(d->hwirq); - rcar_pci_write_reg(pcie, value, PCIEMSIIER); - spin_unlock_irqrestore(&msi->mask_lock, flags); + scoped_guard(raw_spinlock_irqsave, &msi->mask_lock) { + value = rcar_pci_read_reg(pcie, PCIEMSIIER); + value &= ~BIT(d->hwirq); + rcar_pci_write_reg(pcie, value, PCIEMSIIER); + } }
static void rcar_msi_irq_unmask(struct irq_data *d) { struct rcar_msi *msi = irq_data_get_irq_chip_data(d); struct rcar_pcie *pcie = &msi_to_host(msi)->pcie; - unsigned long flags; u32 value;
- spin_lock_irqsave(&msi->mask_lock, flags); - value = rcar_pci_read_reg(pcie, PCIEMSIIER); - value |= BIT(d->hwirq); - rcar_pci_write_reg(pcie, value, PCIEMSIIER); - spin_unlock_irqrestore(&msi->mask_lock, flags); + scoped_guard(raw_spinlock_irqsave, &msi->mask_lock) { + value = rcar_pci_read_reg(pcie, PCIEMSIIER); + value |= BIT(d->hwirq); + rcar_pci_write_reg(pcie, value, PCIEMSIIER); + } }
static void rcar_compose_msi_msg(struct irq_data *data, struct msi_msg *msg) @@ -736,7 +735,7 @@ static int rcar_pcie_enable_msi(struct rcar_pcie_host *host) int err;
mutex_init(&msi->map_lock); - spin_lock_init(&msi->mask_lock); + raw_spin_lock_init(&msi->mask_lock);
err = of_address_to_resource(dev->of_node, 0, &res); if (err)
linux-stable-mirror@lists.linaro.org
-
Marek Vasut