From: Marek Vasut Date: Tue, 9 Sep 2025 16:26:24 +0000 (+0200) Subject: PCI: rcar-host: Drop PMSR spinlock X-Git-Tag: v6.18-rc1~60^2~6^2~1 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=0a8f173d9dad13930d5888505dc4c4fd6a1d4262;p=thirdparty%2Fkernel%2Fstable.git PCI: rcar-host: Drop PMSR spinlock 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 The rcar_pcie_aarch32_abort_handler() case is no longer applicable since commit 6e36203bc14c ("PCI: rcar: Use PCI_SET_ERROR_RESPONSE after read which triggered an exception"), which performs more accurate, controlled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' . It should be noted that 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 Reported-by: Thuan Nguyen Signed-off-by: Marek Vasut Signed-off-by: Manivannan Sadhasivam Reviewed-by: Geert Uytterhoeven Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20250909162707.13927-1-marek.vasut+renesas@mailbox.org --- diff --git a/drivers/pci/controller/pcie-rcar-host.c b/drivers/pci/controller/pcie-rcar-host.c index 4780e0109e58..625a00f3b223 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; }