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The rcar_pcie_aarch32_abort_handler() case is no longer applicable since commit 6e36203bc14c ("PCI: rcar: Use PCI_SET_ERROR_RESPONSE after read which triggered an exception"), which performs more accurate, controlled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; }