PCI: rcar-host: Convert struct rcar_msi mask_lock into raw spinlock

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>
Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
Signed-off-by: Manivannan Sadhasivam <mani@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20250909162707.13927-2-marek.vasut+renesas@mailbox.org

diff --git a/drivers/pci/controller/pcie-rcar-host.c b/drivers/pci/controller/pcie-rcar-host.c
index 625a00f3b2230023c602fd65a66b8d08a15d55ca..213028052aa5891546da4a14cc3462ce5ae51a5a 100644 (file)
--- 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)