> -----Original Message-----
> From: Tomas Henzl [mailto:the...@redhat.com]
> Sent: Tuesday, January 19, 2016 8:14 AM
> To: Raghava Aditya Renukunta; james.bottom...@hansenpartnership.com;
> martin.peter...@oracle.com; linux-scsi@vger.kernel.org
> Cc: Mahesh Rajashekhara; Murthy Bhat; Gana Sridaran; aacraid@pmc-
> sierra.com; Scott Benesh; jthumsh...@suse.de; shane.seym...@hpe.com;
> David Carroll
> Subject: Re: [PATCH V3 7/9] aacraid: Fix AIF triggered IOP_RESET
>
> On 15.1.2016 08:16, Raghava Aditya Renukunta wrote:
> > From: Raghava Aditya Renukunta <raghavaaditya.renuku...@pmcs.com>
> >
> > while driver removal is in progress or PCI shutdown is invoked, driver
> > kills AIF aacraid thread, but IOCTL requests from the management tools
> > re-start AIF thread leading to IOP_RESET.
> >
> > Fixed by setting adapter_shutdown flag when PCI shutdown is invoked.
> >
> > Changes in V2:
> > Set adapter_shutdown flag before shutdown command is sent to \
> > controller
> >
> > Changes in V3:
> > Call aac_send_shut_shutdown first thing in __aac_shutdown
> > Convert adapter_shutdown to atomic_t variable to prevent \
> > SMP coherency issues(race conditions)
>
> Hi,
> I don't think that an atomic variable can change it, imagine that
> thread just passed your test in aac_cfg_ioctl and another thread
> enter a bit later the adapter_shutdown so both - an I/O and your shutdown
> code
> will run in parallel.
> Also you need to fix your compat_ioctl path too.
>
> --tm
Hello Tomas,
Yes that would not solve this problem.
I can think of 2 solutions
1.Place a delay after setting adapter_shutdown and before sending the actual
shutdown command in aac_send_shutdown. This way any impending commands will be
processed before the adapter actually receives the shutdown command. Since
management
commands are sync only , shutdown command will be sent last. This solution uses
an
estimation of the delay
2.Since commands are sync , place a check in aac_fib_send to block
commands once adapter_shutdown is set(only shutdown command will be sent thru)
I am more inclined to go with option 2.
Regards,
Raghava Aditya
> >
> > Signed-off-by: Raghava Aditya Renukunta
> <raghavaaditya.renuku...@pmcs.com>
> > ---
> > drivers/scsi/aacraid/aacraid.h | 2 +-
> > drivers/scsi/aacraid/comminit.c | 6 +++---
> > drivers/scsi/aacraid/linit.c | 15 ++++++++-------
> > 3 files changed, 12 insertions(+), 11 deletions(-)
> >
> > diff --git a/drivers/scsi/aacraid/aacraid.h b/drivers/scsi/aacraid/aacraid.h
> > index 2916288..3473668 100644
> > --- a/drivers/scsi/aacraid/aacraid.h
> > +++ b/drivers/scsi/aacraid/aacraid.h
> > @@ -1234,7 +1234,7 @@ struct aac_dev
> > int msi_enabled; /* MSI/MSI-X enabled */
> > struct msix_entry msixentry[AAC_MAX_MSIX];
> > struct aac_msix_ctx aac_msix[AAC_MAX_MSIX]; /* context */
> > - u8 adapter_shutdown;
> > + atomic_t adapter_shutdown;
> > u32 handle_pci_error;
> > };
> >
> > diff --git a/drivers/scsi/aacraid/comminit.c
> b/drivers/scsi/aacraid/comminit.c
> > index 0e954e3..d361673 100644
> > --- a/drivers/scsi/aacraid/comminit.c
> > +++ b/drivers/scsi/aacraid/comminit.c
> > @@ -212,8 +212,9 @@ int aac_send_shutdown(struct aac_dev * dev)
> > return -ENOMEM;
> > aac_fib_init(fibctx);
> >
> > - cmd = (struct aac_close *) fib_data(fibctx);
> > + atomic_set(&dev->adapter_shutdown, 1);
> >
> > + cmd = (struct aac_close *) fib_data(fibctx);
> > cmd->command = cpu_to_le32(VM_CloseAll);
> > cmd->cid = cpu_to_le32(0xfffffffe);
> >
> > @@ -229,7 +230,6 @@ int aac_send_shutdown(struct aac_dev * dev)
> > /* FIB should be freed only after getting the response from the F/W
> */
> > if (status != -ERESTARTSYS)
> > aac_fib_free(fibctx);
> > - dev->adapter_shutdown = 1;
> > if ((dev->pdev->device == PMC_DEVICE_S7 ||
> > dev->pdev->device == PMC_DEVICE_S8 ||
> > dev->pdev->device == PMC_DEVICE_S9) &&
> > @@ -468,7 +468,7 @@ struct aac_dev *aac_init_adapter(struct aac_dev
> *dev)
> > }
> > dev->max_msix = 0;
> > dev->msi_enabled = 0;
> > - dev->adapter_shutdown = 0;
> > + atomic_set(&dev->adapter_shutdown, 0);
> > if ((!aac_adapter_sync_cmd(dev,
> GET_COMM_PREFERRED_SETTINGS,
> > 0, 0, 0, 0, 0, 0,
> > status+0, status+1, status+2, status+3, status+4))
> > diff --git a/drivers/scsi/aacraid/linit.c b/drivers/scsi/aacraid/linit.c
> > index 6944560..27b3fcd 100644
> > --- a/drivers/scsi/aacraid/linit.c
> > +++ b/drivers/scsi/aacraid/linit.c
> > @@ -706,7 +706,7 @@ static long aac_cfg_ioctl(struct file *file,
> > int ret;
> > struct aac_dev *aac;
> > aac = (struct aac_dev *)file->private_data;
> > - if (!capable(CAP_SYS_RAWIO) || aac->adapter_shutdown)
> > + if (!capable(CAP_SYS_RAWIO) || atomic_read(&aac-
> >adapter_shutdown))
> > return -EPERM;
> > mutex_lock(&aac_mutex);
> > ret = aac_do_ioctl(file->private_data, cmd, (void __user *)arg);
> > @@ -1078,6 +1078,8 @@ static void __aac_shutdown(struct aac_dev * aac)
> > int i;
> > int cpu;
> >
> > + aac_send_shutdown(aac);
> > +
> > if (aac->aif_thread) {
> > int i;
> > /* Clear out events first */
> > @@ -1089,7 +1091,7 @@ static void __aac_shutdown(struct aac_dev * aac)
> > }
> > kthread_stop(aac->thread);
> > }
> > - aac_send_shutdown(aac);
> > +
> > aac_adapter_disable_int(aac);
> > cpu = cpumask_first(cpu_online_mask);
> > if (aac->pdev->device == PMC_DEVICE_S6 ||
> > @@ -1474,7 +1476,7 @@ static int aac_resume(struct pci_dev *pdev)
> > * reset this flag to unblock ioctl() as it was set at
> > * aac_send_shutdown() to block ioctls from upperlayer
> > */
> > - aac->adapter_shutdown = 0;
> > + atomic_set(&aac->adapter_shutdown, 0);
> > scsi_unblock_requests(shost);
> >
> > return 0;
> > @@ -1553,9 +1555,8 @@ static pci_ers_result_t
> aac_pci_error_detected(struct pci_dev *pdev,
> > case pci_channel_io_normal:
> > return PCI_ERS_RESULT_CAN_RECOVER;
> > case pci_channel_io_frozen:
> > -
> > aac->handle_pci_error = 1;
> > - aac->adapter_shutdown = 1;
> > + atomic_set(&aac->adapter_shutdown, 1);
> >
> > scsi_block_requests(aac->scsi_host_ptr);
> > aac_flush_ios(aac);
> > @@ -1567,7 +1568,7 @@ static pci_ers_result_t
> aac_pci_error_detected(struct pci_dev *pdev,
> > return PCI_ERS_RESULT_NEED_RESET;
> > case pci_channel_io_perm_failure:
> > aac->handle_pci_error = 1;
> > - aac->adapter_shutdown = 1;
> > + atomic_set(&aac->adapter_shutdown, 1);
> >
> > aac_flush_ios(aac);
> > return PCI_ERS_RESULT_DISCONNECT;
> > @@ -1636,7 +1637,7 @@ static void aac_pci_resume(struct pci_dev *pdev)
> > * reset this flag to unblock ioctl() as it was set
> > * at aac_send_shutdown() to block ioctls from upperlayer
> > */
> > - aac->adapter_shutdown = 0;
> > + atomic_set(&aac->adapter_shutdown, 0);
> > aac->handle_pci_error = 0;
> >
> > shost_for_each_device(sdev, shost)
--
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
