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* [PATCH AUTOSEL 4.9 43/66] vfio/pci: Fix potential memory leak in vfio_msi_cap_len
       [not found] <20191110024846.32598-1-sashal@kernel.org>
@ 2019-11-10  2:48 ` Sasha Levin
  2019-11-10  2:48 ` [PATCH AUTOSEL 4.9 44/66] vfio/pci: Mask buggy SR-IOV VF INTx support Sasha Levin
  1 sibling, 0 replies; 2+ messages in thread
From: Sasha Levin @ 2019-11-10  2:48 UTC (permalink / raw)
  To: linux-kernel, stable
  Cc: Li Qiang, Eric Auger, Alex Williamson, Sasha Levin, kvm

From: Li Qiang <liq3ea@gmail.com>

[ Upstream commit 30ea32ab1951c80c6113f300fce2c70cd12659e4 ]

Free allocated vdev->msi_perm in error path.

Signed-off-by: Li Qiang <liq3ea@gmail.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/vfio/pci/vfio_pci_config.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/vfio/pci/vfio_pci_config.c b/drivers/vfio/pci/vfio_pci_config.c
index 7b8a957b008d2..06a20ea183dd6 100644
--- a/drivers/vfio/pci/vfio_pci_config.c
+++ b/drivers/vfio/pci/vfio_pci_config.c
@@ -1182,8 +1182,10 @@ static int vfio_msi_cap_len(struct vfio_pci_device *vdev, u8 pos)
 		return -ENOMEM;
 
 	ret = init_pci_cap_msi_perm(vdev->msi_perm, len, flags);
-	if (ret)
+	if (ret) {
+		kfree(vdev->msi_perm);
 		return ret;
+	}
 
 	return len;
 }
-- 
2.20.1


^ permalink raw reply related	[flat|nested] 2+ messages in thread

* [PATCH AUTOSEL 4.9 44/66] vfio/pci: Mask buggy SR-IOV VF INTx support
       [not found] <20191110024846.32598-1-sashal@kernel.org>
  2019-11-10  2:48 ` [PATCH AUTOSEL 4.9 43/66] vfio/pci: Fix potential memory leak in vfio_msi_cap_len Sasha Levin
@ 2019-11-10  2:48 ` Sasha Levin
  1 sibling, 0 replies; 2+ messages in thread
From: Sasha Levin @ 2019-11-10  2:48 UTC (permalink / raw)
  To: linux-kernel, stable
  Cc: Alex Williamson, Gage Eads, Ashok Raj, Sasha Levin, kvm

From: Alex Williamson <alex.williamson@redhat.com>

[ Upstream commit db04264fe9bc0f2b62e036629f9afb530324b693 ]

The SR-IOV spec requires that VFs must report zero for the INTx pin
register as VFs are precluded from INTx support.  It's much easier for
the host kernel to understand whether a device is a VF and therefore
whether a non-zero pin register value is bogus than it is to do the
same in userspace.  Override the INTx count for such devices and
virtualize the pin register to provide a consistent view of the device
to the user.

As this is clearly a spec violation, warn about it to support hardware
validation, but also provide a known whitelist as it doesn't do much
good to continue complaining if the hardware vendor doesn't plan to
fix it.

Known devices with this issue: 8086:270c

Tested-by: Gage Eads <gage.eads@intel.com>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/vfio/pci/vfio_pci.c        |  8 ++++++--
 drivers/vfio/pci/vfio_pci_config.c | 27 +++++++++++++++++++++++++++
 2 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
index a1a712d18e028..da3f0ed18c769 100644
--- a/drivers/vfio/pci/vfio_pci.c
+++ b/drivers/vfio/pci/vfio_pci.c
@@ -426,10 +426,14 @@ static int vfio_pci_get_irq_count(struct vfio_pci_device *vdev, int irq_type)
 {
 	if (irq_type == VFIO_PCI_INTX_IRQ_INDEX) {
 		u8 pin;
+
+		if (!IS_ENABLED(CONFIG_VFIO_PCI_INTX) ||
+		    vdev->nointx || vdev->pdev->is_virtfn)
+			return 0;
+
 		pci_read_config_byte(vdev->pdev, PCI_INTERRUPT_PIN, &pin);
-		if (IS_ENABLED(CONFIG_VFIO_PCI_INTX) && !vdev->nointx && pin)
-			return 1;
 
+		return pin ? 1 : 0;
 	} else if (irq_type == VFIO_PCI_MSI_IRQ_INDEX) {
 		u8 pos;
 		u16 flags;
diff --git a/drivers/vfio/pci/vfio_pci_config.c b/drivers/vfio/pci/vfio_pci_config.c
index 06a20ea183dd6..84905d074c4ff 100644
--- a/drivers/vfio/pci/vfio_pci_config.c
+++ b/drivers/vfio/pci/vfio_pci_config.c
@@ -1608,6 +1608,15 @@ static int vfio_ecap_init(struct vfio_pci_device *vdev)
 	return 0;
 }
 
+/*
+ * Nag about hardware bugs, hopefully to have vendors fix them, but at least
+ * to collect a list of dependencies for the VF INTx pin quirk below.
+ */
+static const struct pci_device_id known_bogus_vf_intx_pin[] = {
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x270c) },
+	{}
+};
+
 /*
  * For each device we allocate a pci_config_map that indicates the
  * capability occupying each dword and thus the struct perm_bits we
@@ -1673,6 +1682,24 @@ int vfio_config_init(struct vfio_pci_device *vdev)
 	if (pdev->is_virtfn) {
 		*(__le16 *)&vconfig[PCI_VENDOR_ID] = cpu_to_le16(pdev->vendor);
 		*(__le16 *)&vconfig[PCI_DEVICE_ID] = cpu_to_le16(pdev->device);
+
+		/*
+		 * Per SR-IOV spec rev 1.1, 3.4.1.18 the interrupt pin register
+		 * does not apply to VFs and VFs must implement this register
+		 * as read-only with value zero.  Userspace is not readily able
+		 * to identify whether a device is a VF and thus that the pin
+		 * definition on the device is bogus should it violate this
+		 * requirement.  We already virtualize the pin register for
+		 * other purposes, so we simply need to replace the bogus value
+		 * and consider VFs when we determine INTx IRQ count.
+		 */
+		if (vconfig[PCI_INTERRUPT_PIN] &&
+		    !pci_match_id(known_bogus_vf_intx_pin, pdev))
+			pci_warn(pdev,
+				 "Hardware bug: VF reports bogus INTx pin %d\n",
+				 vconfig[PCI_INTERRUPT_PIN]);
+
+		vconfig[PCI_INTERRUPT_PIN] = 0; /* Gratuitous for good VFs */
 	}
 
 	if (!IS_ENABLED(CONFIG_VFIO_PCI_INTX) || vdev->nointx)
-- 
2.20.1


^ permalink raw reply related	[flat|nested] 2+ messages in thread

end of thread, other threads:[~2019-11-10  2:56 UTC | newest]

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     [not found] <20191110024846.32598-1-sashal@kernel.org>
2019-11-10  2:48 ` [PATCH AUTOSEL 4.9 43/66] vfio/pci: Fix potential memory leak in vfio_msi_cap_len Sasha Levin
2019-11-10  2:48 ` [PATCH AUTOSEL 4.9 44/66] vfio/pci: Mask buggy SR-IOV VF INTx support Sasha Levin

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