* [PATCH] PCI: Fix missing lockdep annotation for pci_cfg_access_trylock()
@ 2024-05-25 1:19 Dan Williams
2024-05-28 15:35 ` Dave Jiang
2024-05-28 22:18 ` Bjorn Helgaas
0 siblings, 2 replies; 3+ messages in thread
From: Dan Williams @ 2024-05-25 1:19 UTC (permalink / raw)
To: bhelgaas; +Cc: Alex Williamson, Alex Williamson, Dave Jiang, linux-pci,
linux-cxl
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.williamson@redhat.com>
Closes: http://lore.kernel.org/r/20240523131005.5578e3de.alex.williamson@redhat.com
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Dan Williams <dan.j.williams@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);
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] PCI: Fix missing lockdep annotation for pci_cfg_access_trylock()
2024-05-25 1:19 [PATCH] PCI: Fix missing lockdep annotation for pci_cfg_access_trylock() Dan Williams
@ 2024-05-28 15:35 ` Dave Jiang
2024-05-28 22:18 ` Bjorn Helgaas
1 sibling, 0 replies; 3+ messages in thread
From: Dave Jiang @ 2024-05-28 15:35 UTC (permalink / raw)
To: Dan Williams, bhelgaas; +Cc: Alex Williamson, linux-pci, linux-cxl
On 5/24/24 6:19 PM, Dan Williams wrote:
> 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.williamson@redhat.com>
> Closes: http://lore.kernel.org/r/20240523131005.5578e3de.alex.williamson@redhat.com
> Tested-by: Alex Williamson <alex.williamson@redhat.com>
> Cc: Dave Jiang <dave.jiang@intel.com>
> Cc: Bjorn Helgaas <bhelgaas@google.com>
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@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);
>
>
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] PCI: Fix missing lockdep annotation for pci_cfg_access_trylock()
2024-05-25 1:19 [PATCH] PCI: Fix missing lockdep annotation for pci_cfg_access_trylock() Dan Williams
2024-05-28 15:35 ` Dave Jiang
@ 2024-05-28 22:18 ` Bjorn Helgaas
1 sibling, 0 replies; 3+ messages in thread
From: Bjorn Helgaas @ 2024-05-28 22:18 UTC (permalink / raw)
To: Dan Williams; +Cc: bhelgaas, Alex Williamson, Dave Jiang, linux-pci, linux-cxl
On Fri, May 24, 2024 at 06:19:13PM -0700, Dan Williams wrote:
> 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.williamson@redhat.com>
> Closes: http://lore.kernel.org/r/20240523131005.5578e3de.alex.williamson@redhat.com
> Tested-by: Alex Williamson <alex.williamson@redhat.com>
> Cc: Dave Jiang <dave.jiang@intel.com>
> Cc: Bjorn Helgaas <bhelgaas@google.com>
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Applied with Dave's Reviewed-by to for-linus for v6.10, thanks!
> ---
> 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);
>
>
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2024-05-28 22:18 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2024-05-25 1:19 [PATCH] PCI: Fix missing lockdep annotation for pci_cfg_access_trylock() Dan Williams
2024-05-28 15:35 ` Dave Jiang
2024-05-28 22:18 ` Bjorn Helgaas
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox