From: Dan Williams <dan.j.willi...@intel.com>

Alex reports a new vfio-pci lockdep warning resulting from the
cfg_access_lock lock_map added recently.

Add the missing annotation to pci_cfg_access_trylock() and adjust the
lock_map acquisition to be symmetrical relative to pci_lock.

Fixes: 7e89efc6e9e4 ("PCI: Lock upstream bridge for pci_reset_function()")
Reported-by: Alex Williamson <alex.william...@redhat.com>
Closes: 
http://lore.kernel.org/r/20240523131005.5578e3de.alex.william...@redhat.com
Tested-by: Alex Williamson <alex.william...@redhat.com>
Cc: Dave Jiang <dave.ji...@intel.com>
Cc: Bjorn Helgaas <bhelg...@google.com>
Signed-off-by: Dan Williams <dan.j.willi...@intel.com>
Reviewed-by: Dave Jiang <dave.ji...@intel.com>
---
 drivers/pci/access.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/pci/access.c b/drivers/pci/access.c
index 30f031de9cfe..3595130ff719 100644
--- a/drivers/pci/access.c
+++ b/drivers/pci/access.c
@@ -289,11 +289,10 @@ void pci_cfg_access_lock(struct pci_dev *dev)
 {
        might_sleep();
 
-       lock_map_acquire(&dev->cfg_access_lock);
-
        raw_spin_lock_irq(&pci_lock);
        if (dev->block_cfg_access)
                pci_wait_cfg(dev);
+       lock_map_acquire(&dev->cfg_access_lock);
        dev->block_cfg_access = 1;
        raw_spin_unlock_irq(&pci_lock);
 }
@@ -315,8 +314,10 @@ bool pci_cfg_access_trylock(struct pci_dev *dev)
        raw_spin_lock_irqsave(&pci_lock, flags);
        if (dev->block_cfg_access)
                locked = false;
-       else
+       else {
+               lock_map_acquire(&dev->cfg_access_lock);
                dev->block_cfg_access = 1;
+       }
        raw_spin_unlock_irqrestore(&pci_lock, flags);
 
        return locked;
@@ -342,11 +343,10 @@ void pci_cfg_access_unlock(struct pci_dev *dev)
        WARN_ON(!dev->block_cfg_access);
 
        dev->block_cfg_access = 0;
+       lock_map_release(&dev->cfg_access_lock);
        raw_spin_unlock_irqrestore(&pci_lock, flags);
 
        wake_up_all(&pci_cfg_wait);
-
-       lock_map_release(&dev->cfg_access_lock);
 }
 EXPORT_SYMBOL_GPL(pci_cfg_access_unlock);
 
-- 
2.39.2

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