[PATCH v2] iommu/ipmmu-vmsa: Allow PCIe devices

[PATCH v2] iommu/ipmmu-vmsa: Allow PCIe devices

[Yoshihiro Shimoda]

To allow PCIe devices, add a new condition whether the device is
a PCI device or not in the ipmmu_device_is_allowed().

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
---
 Changes from v1:
 https://lore.kernel.org/all/20230421122538.3389336-1-yoshihiro.shimoda.uh@renesas.com/
 - Drop a condition in the ipmmu_attach_device().
 - Drop adding PCIe root devices into the devices_allowlist.
 - Use dev_is_pci() instead of using strcmp() in ipmmu_device_is_allowed().

 drivers/iommu/ipmmu-vmsa.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c
index 9f64c5c9f5b9..6efc99382edb 100644
--- a/drivers/iommu/ipmmu-vmsa.c
+++ b/drivers/iommu/ipmmu-vmsa.c
@@ -19,6 +19,7 @@
 #include <linux/of.h>
 #include <linux/of_device.h>
 #include <linux/of_platform.h>
+#include <linux/pci.h>
 #include <linux/platform_device.h>
 #include <linux/sizes.h>
 #include <linux/slab.h>
@@ -723,6 +724,10 @@ static bool ipmmu_device_is_allowed(struct device *dev)
 	if (soc_device_match(soc_denylist))
 		return false;
 
+	/* Check whether this device is a PCI device */
+	if (dev_is_pci(dev))
+		return true;
+
 	/* Check whether this device can work with the IPMMU */
 	for (i = 0; i < ARRAY_SIZE(devices_allowlist); i++) {
 		if (!strcmp(dev_name(dev), devices_allowlist[i]))
-- 
2.25.1

Re: [PATCH v2] iommu/ipmmu-vmsa: Allow PCIe devices

[Joerg Roedel]

On Wed, Apr 26, 2023 at 05:25:11PM +0900, Yoshihiro Shimoda wrote:
> To allow PCIe devices, add a new condition whether the device is
> a PCI device or not in the ipmmu_device_is_allowed().

This needs more explanation on why PCI devices are safe to be allowed.
Without this context it looks just too dangerous.

Regards,

	Joerg

RE: [PATCH v2] iommu/ipmmu-vmsa: Allow PCIe devices

[Yoshihiro Shimoda]

Hello Joerg,

> From: Joerg Roedel, Sent: Tuesday, May 23, 2023 12:31 AM
> 
> On Wed, Apr 26, 2023 at 05:25:11PM +0900, Yoshihiro Shimoda wrote:
> > To allow PCIe devices, add a new condition whether the device is
> > a PCI device or not in the ipmmu_device_is_allowed().
> 
> This needs more explanation on why PCI devices are safe to be allowed.
> Without this context it looks just too dangerous.

Thank you for your review. I'll revise the description on v3.

Best regards,
Yoshihiro Shimoda

> Regards,
> 
> 	Joerg
>