Re: SATA resume slowness, e1000 MSI warning

[Andrew Morton <akpm@linux-foundation.org>]

On Wed, 07 Mar 2007 12:28:11 -0700 ebiederm@xmission.com (Eric W. Biederman) wrote:

> Below is an additional set of warnings that should help debug this.
> The old code just got lucky that it triggered a warning when this happens.
> 
> diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
> index 01869b1..5113913 100644
> --- a/drivers/pci/msi.c
> +++ b/drivers/pci/msi.c
> @@ -613,6 +613,7 @@ int pci_enable_msi(struct pci_dev* dev)
>  		return -EINVAL;
>  
>  	WARN_ON(!!dev->msi_enabled);
> +	WARN_ON(!hlist_empty(&dev->saved_cap_space));
>  
>  	/* Check whether driver already requested for MSI-X irqs */
>  	if (dev->msix_enabled) {
> @@ -638,6 +639,8 @@ void pci_disable_msi(struct pci_dev* dev)
>  	if (!dev->msi_enabled)
>  		return;
>  
> +	WARN_ON(!hlist_empty(&dev->saved_cap_space));
> +
>  	msi_set_enable(dev, 0);
>  	pci_intx(dev, 1);		/* enable intx */
>  	dev->msi_enabled = 0;
> @@ -739,6 +742,7 @@ int pci_enable_msix(struct pci_dev* dev, struct msix_entry *entries, int nvec)
>  		}
>  	}
>  	WARN_ON(!!dev->msix_enabled);
> +	WARN_ON(!hlist_empty(&dev->saved_cap_space));
>  
>  	/* Check whether driver already requested for MSI irq */
>     	if (dev->msi_enabled) {
> @@ -763,6 +767,8 @@ void pci_disable_msix(struct pci_dev* dev)
>  	if (!dev->msix_enabled)
>  		return;
>  
> +	WARN_ON(!hlist_empty(&dev->saved_cap_space));
> +
>  	msix_set_enable(dev, 0);
>  	pci_intx(dev, 1);		/* enable intx */
>  	dev->msix_enabled = 0;
> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
> index bd44a48..4418839 100644
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -677,6 +677,7 @@ pci_restore_state(struct pci_dev *dev)
>  	}
>  	pci_restore_pcix_state(dev);
>  	pci_restore_msi_state(dev);
> +	WARN_ON(!hlist_empty(&dev->saved_cap_space));
>  
>  	return 0;
>  }

Got a hit on a powerpc g5:

PM: Writing back config space on device 0001:05:04.0 at offset 1 (was 2b00000, writing 2b00006)
------------[ cut here ]------------
Badness at drivers/pci/pci.c:679
Call Trace:
[C0000000080F7410] [C000000000011EFC] .show_stack+0x50/0x1cc (unreliable)
[C0000000080F74C0] [C0000000001AD610] .report_bug+0xa0/0x110
[C0000000080F7550] [C0000000000256E4] .program_check_exception+0xb4/0x670
[C0000000080F7630] [C0000000000046F4] program_check_common+0xf4/0x100
--- Exception: 700 at .pci_restore_state+0x310/0x340
    LR = .pci_restore_state+0x2e0/0x340
[C0000000080F79D0] [C00000000026A174] .tg3_chip_reset+0x19c/0xa04
[C0000000080F7A90] [C00000000026D948] .tg3_reset_hw+0xa4/0x2718
[C0000000080F7BA0] [C000000000270030] .tg3_init_hw+0x74/0x94
[C0000000080F7C30] [C000000000270BE0] .tg3_open+0x4c8/0x854
[C0000000080F7CF0] [C0000000003A74A4] .dev_open+0x100/0x12c
[C0000000080F7D90] [C0000000003BAEA8] .netpoll_setup+0x2dc/0x3ec
[C0000000080F7E40] [C000000000283450] .init_netconsole+0x64/0x8c
[C0000000080F7EC0] [C0000000005C0BE4] .init+0x1d0/0x390
[C0000000080F7F90] [C0000000000271F8] .kernel_thread+0x4c/0x68
tg3: eth0: Link is up at 1000 Mbps, full duplex.
tg3: eth0: Flow control is on for TX and on for RX.
Scheduler bitmap error - bitmap being reconstructed..
netconsole: network logging started
Calling initcall 0xc0000000006bd180: .macio_module_init+0x0/0x3c()

That's:

        pci_restore_pcix_state(dev);
        pci_restore_msi_state(dev);
        WARN_ON(!hlist_empty(&dev->saved_cap_space));

        return 0;