diff mbox series

[36/39] PCI/MSI: Validate MSIX contiguous restriction early

Message ID 20221111122015.691357406@linutronix.de
State New
Headers
Series genirq, PCI/MSI: Support for per device MSI and PCI/IMS - Part 1 cleanups |

Commit Message

Thomas Gleixner Nov. 11, 2022, 1:55 p.m. UTC 
  With interrupt domains the sanity check for MSI-X vector validation can be
done _before_ any allocation happens. The sanity check only applies to the
allocation functions which have an 'entries' array argument. The entries
array is filled by the caller with the requested MSI-X indicies. Some drivers
have gaps in the index space which is not supported on all architectures.

The PCI/MSI irqdomain has a 'feature' bit to enforce this validation late
during the allocation phase.

Just do it right away before doing any other work along with the other
sanity checks on that array.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
 drivers/pci/msi/msi.c |   11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

Comments

Bjorn Helgaas Nov. 16, 2022, 4:33 p.m. UTC | #1 
On Fri, Nov 11, 2022 at 02:55:12PM +0100, Thomas Gleixner wrote:
> With interrupt domains the sanity check for MSI-X vector validation can be
> done _before_ any allocation happens. The sanity check only applies to the
> allocation functions which have an 'entries' array argument. The entries
> array is filled by the caller with the requested MSI-X indicies. Some drivers
> have gaps in the index space which is not supported on all architectures.
> 
> The PCI/MSI irqdomain has a 'feature' bit to enforce this validation late
> during the allocation phase.
> 
> Just do it right away before doing any other work along with the other
> sanity checks on that array.
> 
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Acked-by: Bjorn Helgaas <bhelgaas@google.com>

s/indicies/indices/ (commit log)
s/irqdomain/irq domain/?  IIRC previous logs used "irq domain"
s/MSIX/MSI-X/ (subject line)

> ---
>  drivers/pci/msi/msi.c |   11 +++++++++--
>  1 file changed, 9 insertions(+), 2 deletions(-)
> 
> --- a/drivers/pci/msi/msi.c
> +++ b/drivers/pci/msi/msi.c
> @@ -725,13 +725,17 @@ static int msix_capability_init(struct p
>  	return ret;
>  }
>  
> -static bool pci_msix_validate_entries(struct msix_entry *entries, int nvec, int hwsize)
> +static bool pci_msix_validate_entries(struct pci_dev *dev, struct msix_entry *entries,
> +				      int nvec, int hwsize)
>  {
> +	bool nogap;
>  	int i, j;
>  
>  	if (!entries)
>  		return true;
>  
> +	nogap = pci_msi_domain_supports(dev, MSI_FLAG_MSIX_CONTIGUOUS, DENY_LEGACY);
> +
>  	for (i = 0; i < nvec; i++) {
>  		/* Entry within hardware limit? */
>  		if (entries[i].entry >= hwsize)
> @@ -742,6 +746,9 @@ static bool pci_msix_validate_entries(st
>  			if (entries[i].entry == entries[j].entry)
>  				return false;
>  		}
> +		/* Check for unsupported gaps */
> +		if (nogap && entries[i].entry != i)
> +			return false;
>  	}
>  	return true;
>  }
> @@ -773,7 +780,7 @@ int __pci_enable_msix_range(struct pci_d
>  	if (hwsize < 0)
>  		return hwsize;
>  
> -	if (!pci_msix_validate_entries(entries, nvec, hwsize))
> +	if (!pci_msix_validate_entries(dev, entries, nvec, hwsize))
>  		return -EINVAL;
>  
>  	/* PCI_IRQ_VIRTUAL is a horrible hack! */
>
Jason Gunthorpe Nov. 16, 2022, 6 p.m. UTC | #2 
On Fri, Nov 11, 2022 at 02:55:12PM +0100, Thomas Gleixner wrote:
> With interrupt domains the sanity check for MSI-X vector validation can be
> done _before_ any allocation happens. The sanity check only applies to the
> allocation functions which have an 'entries' array argument. The entries
> array is filled by the caller with the requested MSI-X indicies. Some drivers
> have gaps in the index space which is not supported on all architectures.
> 
> The PCI/MSI irqdomain has a 'feature' bit to enforce this validation late
> during the allocation phase.
> 
> Just do it right away before doing any other work along with the other
> sanity checks on that array.
> 
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> ---
>  drivers/pci/msi/msi.c |   11 +++++++++--
>  1 file changed, 9 insertions(+), 2 deletions(-)

Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>

Jason
diff mbox series

Patch

--- a/drivers/pci/msi/msi.c
+++ b/drivers/pci/msi/msi.c
@@ -725,13 +725,17 @@  static int msix_capability_init(struct p
 	return ret;
 }
 
-static bool pci_msix_validate_entries(struct msix_entry *entries, int nvec, int hwsize)
+static bool pci_msix_validate_entries(struct pci_dev *dev, struct msix_entry *entries,
+				      int nvec, int hwsize)
 {
+	bool nogap;
 	int i, j;
 
 	if (!entries)
 		return true;
 
+	nogap = pci_msi_domain_supports(dev, MSI_FLAG_MSIX_CONTIGUOUS, DENY_LEGACY);
+
 	for (i = 0; i < nvec; i++) {
 		/* Entry within hardware limit? */
 		if (entries[i].entry >= hwsize)
@@ -742,6 +746,9 @@  static bool pci_msix_validate_entries(st
 			if (entries[i].entry == entries[j].entry)
 				return false;
 		}
+		/* Check for unsupported gaps */
+		if (nogap && entries[i].entry != i)
+			return false;
 	}
 	return true;
 }
@@ -773,7 +780,7 @@  int __pci_enable_msix_range(struct pci_d
 	if (hwsize < 0)
 		return hwsize;
 
-	if (!pci_msix_validate_entries(entries, nvec, hwsize))
+	if (!pci_msix_validate_entries(dev, entries, nvec, hwsize))
 		return -EINVAL;
 
 	/* PCI_IRQ_VIRTUAL is a horrible hack! */