The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x 0a8f173d9dad13930d5888505dc4c4fd6a1d4262 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2025101648-abruptly-poncho-afdd@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 0a8f173d9dad13930d5888505dc4c4fd6a1d4262 Mon Sep 17 00:00:00 2001 From: Marek Vasut marek.vasut+renesas@mailbox.org Date: Tue, 9 Sep 2025 18:26:24 +0200 Subject: [PATCH] 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The rcar_pcie_aarch32_abort_handler() case is no longer applicable since commit 6e36203bc14c ("PCI: rcar: Use PCI_SET_ERROR_RESPONSE after read which triggered an exception"), which performs more accurate, controlled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 duy.nguyen.rh@renesas.com Reported-by: Thuan Nguyen thuan.nguyen-hong@banvien.com.vn Signed-off-by: Marek Vasut marek.vasut+renesas@mailbox.org Signed-off-by: Manivannan Sadhasivam mani@kernel.org Reviewed-by: Geert Uytterhoeven geert+renesas@glider.be Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20250909162707.13927-1-marek.vasut+renesas@mailbox....
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; }