On Mon, Jul 15, 2019 at 06:56:12PM +1000, Oliver O'Halloran wrote: > The eeh_sysfs_remove_device() function is supposed to clear the > EEH_DEV_SYSFS flag since it indicates the EEH sysfs entries have been added > for a pci_dev. > > When the sysfs files are removed eeh_remove_device() the eeh_dev and the > pci_dev have already been de-associated. This then causes the > pci_dev_to_eeh_dev() call in eeh_sysfs_remove_device() to return NULL so > the flag can't be cleared from the still-live eeh_dev. This problem is > worked around in the caller by clearing the flag manually. However, this > behaviour doesn't make a whole lot of sense, so this patch fixes it by: > > a) Re-ordering eeh_remove_device() so that eeh_sysfs_remove_device() is > called before de-associating the pci_dev and eeh_dev. > > b) Making eeh_sysfs_remove_device() emit a warning if there's no > corresponding eeh_dev for a pci_dev. The paths where the sysfs > files are only reachable if EEH was setup for the device > for the device in the first place so hitting this warning > indicates a programming error. > > Signed-off-by: Oliver O'Halloran <ooh...@gmail.com>
Good cleanup, although it looks like "for the device" got duplicated in
the last part of the commit message.
Simple EEH tests still succeeed.
Reviewed-by: Sam Bobroff <sbobr...@linux.ibm.com>
Tested-by: Sam Bobroff <sbobr...@linux.ibm.com>
> + if (!(edev->pe->state & EEH_PE_KEEP))
> + eeh_rmv_from_parent_pe(edev);
> + else
> + edev->mode |= EEH_DEV_DISCONNECTED;
> ---
> arch/powerpc/kernel/eeh.c | 30 +++++++++++++++++-------------
> arch/powerpc/kernel/eeh_sysfs.c | 15 ++++++++-------
> 2 files changed, 25 insertions(+), 20 deletions(-)
>
> diff --git a/arch/powerpc/kernel/eeh.c b/arch/powerpc/kernel/eeh.c
> index f192d57..6e24896 100644
> --- a/arch/powerpc/kernel/eeh.c
> +++ b/arch/powerpc/kernel/eeh.c
> @@ -1203,7 +1203,6 @@ void eeh_add_device_late(struct pci_dev *dev)
> eeh_rmv_from_parent_pe(edev);
> eeh_addr_cache_rmv_dev(edev->pdev);
> eeh_sysfs_remove_device(edev->pdev);
> - edev->mode &= ~EEH_DEV_SYSFS;
>
> /*
> * We definitely should have the PCI device removed
> @@ -1306,17 +1305,11 @@ void eeh_remove_device(struct pci_dev *dev)
> edev->pdev = NULL;
>
> /*
> - * The flag "in_error" is used to trace EEH devices for VFs
> - * in error state or not. It's set in eeh_report_error(). If
> - * it's not set, eeh_report_{reset,resume}() won't be called
> - * for the VF EEH device.
> + * eeh_sysfs_remove_device() uses pci_dev_to_eeh_dev() so we need to
> + * remove the sysfs files before clearing dev.archdata.edev
> */
> - edev->in_error = false;
> - dev->dev.archdata.edev = NULL;
> - if (!(edev->pe->state & EEH_PE_KEEP))
> - eeh_rmv_from_parent_pe(edev);
> - else
> - edev->mode |= EEH_DEV_DISCONNECTED;
> + if (edev->mode & EEH_DEV_SYSFS)
> + eeh_sysfs_remove_device(dev);
>
> /*
> * We're removing from the PCI subsystem, that means
> @@ -1327,8 +1320,19 @@ void eeh_remove_device(struct pci_dev *dev)
> edev->mode |= EEH_DEV_NO_HANDLER;
>
> eeh_addr_cache_rmv_dev(dev);
> - eeh_sysfs_remove_device(dev);
> - edev->mode &= ~EEH_DEV_SYSFS;
> +
> + /*
> + * The flag "in_error" is used to trace EEH devices for VFs
> + * in error state or not. It's set in eeh_report_error(). If
> + * it's not set, eeh_report_{reset,resume}() won't be called
> + * for the VF EEH device.
> + */
> + edev->in_error = false;
> + dev->dev.archdata.edev = NULL;
> + if (!(edev->pe->state & EEH_PE_KEEP))
> + eeh_rmv_from_parent_pe(edev);
> + else
> + edev->mode |= EEH_DEV_DISCONNECTED;
> }
>
> int eeh_unfreeze_pe(struct eeh_pe *pe)
> diff --git a/arch/powerpc/kernel/eeh_sysfs.c b/arch/powerpc/kernel/eeh_sysfs.c
> index c4cc8fc..5614fd83 100644
> --- a/arch/powerpc/kernel/eeh_sysfs.c
> +++ b/arch/powerpc/kernel/eeh_sysfs.c
> @@ -175,22 +175,23 @@ void eeh_sysfs_remove_device(struct pci_dev *pdev)
> {
> struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev);
>
> + if (!edev) {
> + WARN_ON(eeh_enabled());
> + return;
> + }
> +
> + edev->mode &= ~EEH_DEV_SYSFS;
> +
> /*
> * The parent directory might have been removed. We needn't
> * continue for that case.
> */
> - if (!pdev->dev.kobj.sd) {
> - if (edev)
> - edev->mode &= ~EEH_DEV_SYSFS;
> + if (!pdev->dev.kobj.sd)
> return;
> - }
>
> device_remove_file(&pdev->dev, &dev_attr_eeh_mode);
> device_remove_file(&pdev->dev, &dev_attr_eeh_pe_config_addr);
> device_remove_file(&pdev->dev, &dev_attr_eeh_pe_state);
>
> eeh_notify_resume_remove(pdev);
> -
> - if (edev)
> - edev->mode &= ~EEH_DEV_SYSFS;
> }
> --
> 2.9.5
>
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