diff mbox series

[net-next] liquidio: fix crash in presence of zeroed-out base address regs

Message ID 20170830231953.GA14744@felix-thinkpad.cavium.com
State Accepted, archived
Delegated to: David Miller
Headers show
Series [net-next] liquidio: fix crash in presence of zeroed-out base address regs | expand

Commit Message

Manlunas, Felix Aug. 30, 2017, 11:19 p.m. UTC 
From: Rick Farrington <ricardo.farrington@cavium.com>

Fix crash in linux PF driver when BARs have been cleared/de-programmed;
fail early init (prior to mapping BARs) if the BAR0 or
BAR1 registers are zero.

This situation can arise when the PF is added to a VM (PCI pass-through),
then a PF FLR is issued (in the VM).  After this occurs, the BAR registers
will be zero. If we attempt to load the PF driver in the host
(after VM has been shutdown), the host can reset.

Signed-off-by: Rick Farrington <ricardo.farrington@cavium.com>
Signed-off-by: Raghu Vatsavayi <raghu.vatsavayi@cavium.com>
Signed-off-by: Felix Manlunas <felix.manlunas@cavium.com>
---
 .../net/ethernet/cavium/liquidio/cn23xx_pf_device.c  | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

Comments

David Miller Aug. 31, 2017, 5:07 a.m. UTC | #1 
From: Felix Manlunas <felix.manlunas@cavium.com>
Date: Wed, 30 Aug 2017 16:19:53 -0700

> From: Rick Farrington <ricardo.farrington@cavium.com>
> 
> Fix crash in linux PF driver when BARs have been cleared/de-programmed;
> fail early init (prior to mapping BARs) if the BAR0 or
> BAR1 registers are zero.
> 
> This situation can arise when the PF is added to a VM (PCI pass-through),
> then a PF FLR is issued (in the VM).  After this occurs, the BAR registers
> will be zero. If we attempt to load the PF driver in the host
> (after VM has been shutdown), the host can reset.
> 
> Signed-off-by: Rick Farrington <ricardo.farrington@cavium.com>
> Signed-off-by: Raghu Vatsavayi <raghu.vatsavayi@cavium.com>
> Signed-off-by: Felix Manlunas <felix.manlunas@cavium.com>

Applied, thanks.
diff mbox series

Patch

diff --git a/drivers/net/ethernet/cavium/liquidio/cn23xx_pf_device.c b/drivers/net/ethernet/cavium/liquidio/cn23xx_pf_device.c
index 4b0ca9f..8705e23 100644
--- a/drivers/net/ethernet/cavium/liquidio/cn23xx_pf_device.c
+++ b/drivers/net/ethernet/cavium/liquidio/cn23xx_pf_device.c
@@ -1269,6 +1269,26 @@  static int cn23xx_sriov_config(struct octeon_device *oct)
 
 int setup_cn23xx_octeon_pf_device(struct octeon_device *oct)
 {
+	u32 data32;
+	u64 BAR0, BAR1;
+
+	pci_read_config_dword(oct->pci_dev, PCI_BASE_ADDRESS_0, &data32);
+	BAR0 = (u64)(data32 & ~0xf);
+	pci_read_config_dword(oct->pci_dev, PCI_BASE_ADDRESS_1, &data32);
+	BAR0 |= ((u64)data32 << 32);
+	pci_read_config_dword(oct->pci_dev, PCI_BASE_ADDRESS_2, &data32);
+	BAR1 = (u64)(data32 & ~0xf);
+	pci_read_config_dword(oct->pci_dev, PCI_BASE_ADDRESS_3, &data32);
+	BAR1 |= ((u64)data32 << 32);
+
+	if (!BAR0 || !BAR1) {
+		if (!BAR0)
+			dev_err(&oct->pci_dev->dev, "device BAR0 unassigned\n");
+		if (!BAR1)
+			dev_err(&oct->pci_dev->dev, "device BAR1 unassigned\n");
+		return 1;
+	}
+
 	if (octeon_map_pci_barx(oct, 0, 0))
 		return 1;