sparc/PCI: Fix for panic while enabling SR-IOV

Orabug: 22659268

We noticed this panic while enabling SR-IOV in sparc.

ixgbe 0002:03:00.0 eth4: SR-IOV enabled with 2 VFs
ixgbe 0002:03:00.0: Multiqueue Enabled: Rx Queue count = 4,
		Tx Queue count = 4
ixgbevf: Intel(R) 10 Gigabit PCI Express Virtual Function
		Network Driver - version 2.12.1-k
ixgbevf: Copyright (c) 2009 - 2012 Intel Corporation.
Unable to handle kernel NULL pointer dereference
tsk->{mm,active_mm}->context = 000000000000160c
tsk->{mm,active_mm}->pgd = fff8000408238000
              \|/ ____ \|/
              "@'/ .. \`@"
              /_| \__/ |_\
                 \__U_/
modprobe(3335): Oops [#1]
CPU: 2 PID: 3335 Comm: modprobe Tainted: G           OE
		4.1.12-32.el6uek.sparc64 #1
task: fff8000406f35ca0 ti: fff8000404630000 task.ti: fff8000404630000
TSTATE: 0000008411001606 TPC: 0000000000438ee0 TNPC: 0000000000438f0c
		Y: 00000000 Tainted: G           OE
TPC: <dma_supported+0x20/0x80>
g0: 0000000080000001 g1: 0000000000000000 g2: 00000000ffffffff
					g3: 0000000000000003
g4: fff8000406f35ca0 g5: fff800041896a000 g6: fff8000404630000
					g7: 0000000000000000
o0: 0000000000000000 o1: 0000000000000300 o2: 000000000000000
					1o3: 0000000000000004
o4: fff80004122160d8 o5: 0000000000e37ae5 sp: fff8000404632951
					ret_pc: 00000000007215d0
RPC: <pci_enable_device+0x10/0x40>
l0: fff8000404410090 l1: fff800040441013e l2: 00000000007a768c
					l3: 0000000000000001
l4: fff80004046331d8 l5: fff80004046331f0 l6: e000000000000000
					l7: 0040000000000000
i0: fff8000404410090 i1: ffffffffffffffff i2: fff8000404410180
					i3: 00000000004ace40
i4: 0000000000000000 i5: 2000000000000000 i6: fff8000404632a0
					1i7: 0000000010550ea0
I7: <ixgbevf_probe+0x80/0x4c0 [ixgbevf]>
Call Trace:
 [0000000010550ea0] ixgbevf_probe+0x80/0x4c0 [ixgbevf]
 [00000000007229d4] local_pci_probe+0x34/0xa0
 [0000000000722ae8] pci_call_probe+0xa8/0xe0
 [0000000000722dd0] pci_device_probe+0x50/0x80
 [000000000079c1c0] really_probe+0x140/0x420
 [000000000079c4e4] driver_probe_device+0x44/0xa0
 [000000000079c5c8] __driver_attach+0x88/0xa0
 [000000000079a3cc] bus_for_each_dev+0x6c/0xa0
 [000000000079bd5c] driver_attach+0x1c/0x40
 [000000000079ae1c] bus_add_driver+0x17c/0x220
 [000000000079cd94] driver_register+0x74/0x120
 [0000000000722ebc] __pci_register_driver+0x3c/0x60
 [0000000010558048] ixgbevf_init_module+0x48/0x5c [ixgbevf]
 [0000000000426bb8] do_one_initcall+0xb8/0x200
 [00000000004e5f8c] do_init_module+0x4c/0x1c0
 [00000000004e6f48] load_module+0x5e8/0x780
Disabling lock debugging due to kernel taint
Caller[0000000010550ea0]: ixgbevf_probe+0x80/0x4c0 [ixgbevf]
Caller[00000000007229d4]: local_pci_probe+0x34/0xa0
Caller[0000000000722ae8]: pci_call_probe+0xa8/0xe0
Caller[0000000000722dd0]: pci_device_probe+0x50/0x80
Caller[000000000079c1c0]: really_probe+0x140/0x420
Caller[000000000079c4e4]: driver_probe_device+0x44/0xa0
Caller[000000000079c5c8]: __driver_attach+0x88/0xa0
Caller[000000000079a3cc]: bus_for_each_dev+0x6c/0xa0
Caller[000000000079bd5c]: driver_attach+0x1c/0x40
Caller[000000000079ae1c]: bus_add_driver+0x17c/0x220
Caller[000000000079cd94]: driver_register+0x74/0x120
Caller[0000000000722ebc]: __pci_register_driver+0x3c/0x60
Caller[0000000010558048]: ixgbevf_init_module+0x48/0x5c [ixgbevf]
Caller[0000000000426bb8]: do_one_initcall+0xb8/0x200
Caller[00000000004e5f8c]: do_init_module+0x4c/0x1c0
Caller[00000000004e6f48]: load_module+0x5e8/0x780
Caller[00000000004e7184]: SyS_init_module+0xa4/0xe0
Caller[0000000000406254]: linux_sparc_syscall+0x34/0x44
Caller[0000000000103490]: 0x103490
Instruction DUMP: 8530b020  80a64002  1860000c <c200625c>
		840e4001  80a08001  02400009  90102001  c45e2088
Kernel panic - not syncing: Fatal exception
Press Stop-A (L1-A) to return to the boot prom
---[ end Kernel panic - not syncing: Fatal exception

Details:
Here is the call sequence
virtfn_add->__mlx4_init_one->dma_set_mask->dma_supported

The panic happened at line 760(file arch/sparc/kernel/iommu.c)

758 int dma_supported(struct device *dev, u64 device_mask)
759 {
760         struct iommu *iommu = dev->archdata.iommu;
761         u64 dma_addr_mask = iommu->dma_addr_mask;
762
763         if (device_mask >= (1UL << 32UL))
764                 return 0;
765
766         if ((device_mask & dma_addr_mask) == dma_addr_mask)
767                 return 1;
768
769 #ifdef CONFIG_PCI
770         if (dev_is_pci(dev))
771		return pci64_dma_supported(to_pci_dev(dev), device_mask);
772 #endif
773
774         return 0;
775 }
776 EXPORT_SYMBOL(dma_supported);

Same panic happened with Intel ixgbe driver also.

SR-IOV code looks for arch specific data while enabling
VFs. When VF device is added, driver probe function makes set
of calls to initialize the pci device. Because the VF device is
added different way than the normal PF device(which happens via
of_create_pci_dev for sparc), some of the arch specific initialization
does not happen for VF device.  That causes panic when archdata is
accessed.

To fix this, I have used already defined weak function
pcibios_setup_device to copy archdata from PF to VF.
Also verified the fix.

Signed-off-by: Babu Moger <babu.moger@oracle.com>
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Reviewed-by: Ethan Zhao <ethan.zhao@oracle.com>
Signed-off-by: Allen Pais <allen.pais@oracle.com>
(cherry picked from commit be81c7e3cc48d3ff8b26021be3fd49e997743cbc)

diff --git a/arch/sparc/kernel/pci.c b/arch/sparc/kernel/pci.c
index 2bcef15b0287d647eb8b979994c260e642737b4d..da9eadf93f74cc915b15bdd18c6f207da88f78aa 100644 (file)
--- a/arch/sparc/kernel/pci.c
+++ b/arch/sparc/kernel/pci.c
@@ -1030,6 +1030,23 @@ void pcibios_set_master(struct pci_dev *dev)
        /* No special bus mastering setup handling */
 }
 
+#ifdef CONFIG_PCI_IOV
+int pcibios_add_device(struct pci_dev *dev)
+{
+       struct pci_dev *pdev;
+
+       /* Add sriov arch specific initialization here.
+        * Copy dev_archdata from PF to VF
+        */
+       if (dev->is_virtfn) {
+               pdev = dev->physfn;
+               memcpy(&dev->dev.archdata, &pdev->dev.archdata,
+                      sizeof(struct dev_archdata));
+       }
+       return 0;
+}
+#endif /* CONFIG_PCI_IOV */
+
 static int __init pcibios_init(void)
 {
        pci_dfl_cache_line_size = 64 >> 2;