[PATCH] e1000: fix IRQx nobody cared for shared irq with INTx

[Yinghai Lu <yhlu.kernel.send@gmail.com>]

when try to kexec one latest kernel from kernel.org from RHEL 5.1 got

ACPI: PCI Interrupt 0000:02:00.0[A] -> Link [LNKA] -> GSI 19 (level, low) -> IRQ 19
acpi->mptable 2 : Int: type 0, pol 1, trig 1, bus 02, IRQ 00, APIC ID 0, APIC INT 13
PCI: Setting latency timer of device 0000:02:00.0 to 64
PCI: Enabling Mem-Wr-Inval for device 0000:02:00.0
scsi0 :  on PCI bus 02 device 00 irq 19
irq 19: nobody cared (try booting with the "irqpoll" option)
Pid: 1, comm: swapper Not tainted 2.6.24-smp-07682-g551e4fb-dirty #19

Call Trace:
 <IRQ>  [<ffffffff8026a3eb>] __report_bad_irq+0x30/0x72
 [<ffffffff8026a651>] note_interrupt+0x224/0x26f
 [<ffffffff8026ae78>] handle_fasteoi_irq+0xa5/0xc8
 [<ffffffff8021ffdc>] call_softirq+0x1c/0x28
 [<ffffffff802218e2>] do_IRQ+0xf1/0x15f
 [<ffffffff8021f361>] ret_from_intr+0x0/0xa
 <EOI>  [<ffffffff80785bd6>] pci_mmcfg_write+0x0/0xb0
 [<ffffffff80224dd9>] native_read_tsc+0xd/0x1d
 [<ffffffff804681e7>] __delay+0x17/0x22
 [<ffffffff805cb1a9>] lpfc_sli_brdrestart+0x14c/0x16b
 [<ffffffff805cb264>] lpfc_do_config_port+0x9c/0x3e4
 [<ffffffff802d77a9>] sysfs_link_sibling+0x17/0x31
 [<ffffffff805cb674>] lpfc_sli_hba_setup+0xc8/0x4a2
 [<ffffffff80825397>] lpfc_pci_probe_one+0x750/0x914
 [<ffffffff804728f3>] pci_device_probe+0xb3/0xfb
 [<ffffffff804d958c>] driver_probe_device+0xb5/0x132
 [<ffffffff804d96ab>] __driver_attach+0x0/0x93
 [<ffffffff804d9705>] __driver_attach+0x5a/0x93
 [<ffffffff804d89bc>] bus_for_each_dev+0x44/0x6f
 [<ffffffff804d91b9>] bus_add_driver+0xae/0x1f5
 [<ffffffff804d990e>] driver_register+0x59/0xce
 [<ffffffff80472b56>] __pci_register_driver+0x4a/0x7c
 [<ffffffff80c2d78a>] lpfc_init+0x98/0xba
 [<ffffffff80c0d6e7>] kernel_init+0x175/0x2e1
 [<ffffffff8021fc68>] child_rip+0xa/0x12
 [<ffffffff80c0d572>] kernel_init+0x0/0x2e1
 [<ffffffff8021fc5e>] child_rip+0x0/0x12

handlers:
[<ffffffff805cdbce>] (lpfc_intr_handler+0x0/0x4c6)
Disabling IRQ #19

root caused that there is one Intel card that shared io apic pin and irq with
 lpfc

e1000_probe path only use pci_enable_device to setup irq entry but masked, and
will use e1000_open to use request_irq/setup_irq to install action and
enable/unmask that io apic entry.

but lpfc driver will call it's probe and request_irq/setup_irq. so it
enable/umask that io apic entry. and only lpfc's action the lpfc_intr_handler
is installed.

and some case, the e1000 sent out irq (hw bug or first kernel doesn't call
e1000_irq_disable?)
that irq will confuse the hanlder ... it is not for lpfc_intr_handler...

So try to call pci_intx(dev, 0) in e1000_probe,
and later call pci_intx(dev, 1) after request_irq in e1000_open patch, if the
irq is using INTx

even e1000 is using MSI, still need this patch. Because even pci_enable_msi in
e1000_open path will call pci_intx(dev, 0), that is too late. when we have lpfc
driver loaded before use ifconfig to set network connection.

othe drivers may need to be updated in the same way, if they have same problem
like nobody cared irq with shared INTx irq.

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>

Index: linux-2.6/drivers/net/e1000/e1000_main.c
===================================================================
--- linux-2.6.orig/drivers/net/e1000/e1000_main.c
+++ linux-2.6/drivers/net/e1000/e1000_main.c
@@ -324,6 +324,9 @@ static int e1000_request_irq(struct e100
 			pci_disable_msi(adapter->pdev);
 		DPRINTK(PROBE, ERR,
 		        "Unable to allocate interrupt Error: %d\n", err);
+	} else if (!adapter->have_msi) {
+		/* enable INTx before if not using MSI */
+		pci_intx(adapter->pdev, 1);
 	}
 
 	return err;
@@ -934,6 +937,8 @@ e1000_probe(struct pci_dev *pdev,
 	uint16_t eeprom_apme_mask = E1000_EEPROM_APME;
 	DECLARE_MAC_BUF(mac);
 
+	/* disable INTx at first */
+	pci_intx(pdev, 0);
 	if ((err = pci_enable_device(pdev)))
 		return err;
 
Index: linux-2.6/drivers/net/e1000e/netdev.c
===================================================================
--- linux-2.6.orig/drivers/net/e1000e/netdev.c
+++ linux-2.6/drivers/net/e1000e/netdev.c
@@ -960,6 +960,9 @@ static int e1000_request_irq(struct e100
 			err);
 		if (adapter->flags & FLAG_MSI_ENABLED)
 			pci_disable_msi(adapter->pdev);
+	} else if (!(adapter->flags & FLAG_MSI_ENABLED)) {
+		/* enable INTx before if not using MSI */
+		pci_intx(adapter->pdev, 1);
 	}
 
 	return err;
@@ -3726,6 +3729,8 @@ static int __devinit e1000_probe(struct 
 	u16 eeprom_apme_mask = E1000_EEPROM_APME;
 
 	e1000e_disable_l1aspm(pdev);
+	/* disable INTx at first */
+	pci_intx(pdev, 0);
 	err = pci_enable_device(pdev);
 	if (err)
 		return err;