RE: [PATCH V4 7/9] aacraid: Fix AIF triggered IOP_RESET

Raghava Aditya Renukunta
2016-02-02T01:18:21Z

Hello Tomas,

> -----Original Message-----
> From: Tomas Henzl [mailto:thenzl@redhat.com]
> Sent: Monday, February 1, 2016 8:44 AM
> To: Raghava Aditya Renukunta; James.Bottomley@HansenPartnership.com;
> martin.petersen@oracle.com; linux-scsi@vger.kernel.org
> Cc: Mahesh Rajashekhara; Murthy Bhat; Gana Sridaran; aacraid@pmc-
> sierra.com; Scott Benesh; jthumshirn@suse.de; shane.seymour@hpe.com
> Subject: Re: [PATCH V4 7/9] aacraid: Fix AIF triggered IOP_RESET
>
> On 29.1.2016 23:45, Raghava Aditya Renukunta wrote:
> > From: Raghava Aditya Renukunta <raghavaaditya.renukunta@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)
> >
> > Changes in V4:
> > Used mutex to protect ioctl path and adapter_shutdown to prevent \
> > race conditions.
> >
> > Signed-off-by: Raghava Aditya Renukunta
> <raghavaaditya.renukunta@pmcs.com>
> > Reviewed-by: Shane Seymour <shane.seymour@hpe.com>
> > Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
> > ---
> > drivers/scsi/aacraid/aacraid.h | 2 +-
> > drivers/scsi/aacraid/commctrl.c | 3 ++
> > drivers/scsi/aacraid/comminit.c | 6 ++--
> > drivers/scsi/aacraid/linit.c | 63 +++++++++++++++++++++++++++++++--
> --------
> > 4 files changed, 56 insertions(+), 18 deletions(-)
> >
> > diff --git a/drivers/scsi/aacraid/aacraid.h b/drivers/scsi/aacraid/aacraid.h
> > index 2916288..6c55749 100644
> > --- a/drivers/scsi/aacraid/aacraid.h
> > +++ b/drivers/scsi/aacraid/aacraid.h
> > @@ -1123,7 +1123,7 @@ struct aac_dev
> >
> > struct fib *free_fib;
> > spinlock_t fib_lock;
> > -
> > + struct mutex ioctl_mutex;
> > struct aac_queue_block *queues;
> > /*
> > * The user API will use an IOCTL to register itself to receive
> > diff --git a/drivers/scsi/aacraid/commctrl.c
> b/drivers/scsi/aacraid/commctrl.c
> > index 54195a1..8d3438c 100644
> > --- a/drivers/scsi/aacraid/commctrl.c
> > +++ b/drivers/scsi/aacraid/commctrl.c
> > @@ -855,6 +855,9 @@ int aac_do_ioctl(struct aac_dev * dev, int cmd, void
> __user *arg)
> > {
> > int status;
> >
> > + if (dev->adapter_shutdown)
> > + return -EACCES;
> > +
> > /*
> > * HBA gets first crack
> > */
> > diff --git a/drivers/scsi/aacraid/comminit.c
> b/drivers/scsi/aacraid/comminit.c
> > index 0e954e3..2b4e753 100644
> > --- a/drivers/scsi/aacraid/comminit.c
> > +++ b/drivers/scsi/aacraid/comminit.c
> > @@ -212,8 +212,11 @@ int aac_send_shutdown(struct aac_dev * dev)
> > return -ENOMEM;
> > aac_fib_init(fibctx);
> >
> > - cmd = (struct aac_close *) fib_data(fibctx);
> > + mutex_lock(&dev->ioctl_mutex);
> > + dev->adapter_shutdown = 1;
> > + mutex_unlock(&dev->ioctl_mutex);
> >
> > + cmd = (struct aac_close *) fib_data(fibctx);
> > cmd->command = cpu_to_le32(VM_CloseAll);
> > cmd->cid = cpu_to_le32(0xfffffffe);
> >
> > @@ -229,7 +232,6 @@ 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) &&
> > diff --git a/drivers/scsi/aacraid/linit.c b/drivers/scsi/aacraid/linit.c
> > index af8974e..9453e11 100644
> > --- a/drivers/scsi/aacraid/linit.c
> > +++ b/drivers/scsi/aacraid/linit.c
> > @@ -524,10 +524,17 @@ static struct device_attribute *aac_dev_attrs[] = {
> >
> > static int aac_ioctl(struct scsi_device *sdev, int cmd, void __user * arg)
> > {
> > - struct aac_dev *dev = (struct aac_dev *)sdev->host->hostdata;
> > + int ret;
> > + struct aac_dev *aac = (struct aac_dev *)sdev->host->hostdata;
> > +
> > if (!capable(CAP_SYS_RAWIO))
> > return -EPERM;
> > - return aac_do_ioctl(dev, cmd, arg);
> > +
> > + mutex_lock(&aac->ioctl_mutex);
> > + ret = aac_do_ioctl(aac, cmd, arg);
> > + mutex_unlock(&aac->ioctl_mutex);
> > +
> > + return ret;
> > }
> >
> > static int aac_eh_abort(struct scsi_cmnd* cmd)
> > @@ -704,13 +711,14 @@ static long aac_cfg_ioctl(struct file *file,
> > unsigned int cmd, unsigned long arg)
> > {
> > int ret;
> > - struct aac_dev *aac;
> > - aac = (struct aac_dev *)file->private_data;
> > - if (!capable(CAP_SYS_RAWIO) || aac->adapter_shutdown)
> > + struct aac_dev *aac = (struct aac_dev *)file->private_data;
> > +
> > + if (!capable(CAP_SYS_RAWIO))
> > return -EPERM;
> > - mutex_lock(&aac_mutex);
> > - ret = aac_do_ioctl(file->private_data, cmd, (void __user *)arg);
> > - mutex_unlock(&aac_mutex);
> > +
> > + mutex_lock(&aac->ioctl_mutex);
> > + ret = aac_do_ioctl(aac, cmd, (void __user *)arg);
> > + mutex_unlock(&aac->ioctl_mutex);
> >
> > return ret;
> > }
> > @@ -719,7 +727,10 @@ static long aac_cfg_ioctl(struct file *file,
> > static long aac_compat_do_ioctl(struct aac_dev *dev, unsigned cmd,
> unsigned long arg)
> > {
> > long ret;
> > - mutex_lock(&aac_mutex);
> > +
> > + if (dev->adapter_shutdown)
> > + return -EACCES;
>
> There is another test for the same in aac_do_ioctl, this duplicated test is
> needless.

Will remove

> > +
> > switch (cmd) {
> > case FSACTL_MINIPORT_REV_CHECK:
> > case FSACTL_SENDFIB:
> > @@ -753,23 +764,37 @@ static long aac_compat_do_ioctl(struct aac_dev
> *dev, unsigned cmd, unsigned long
> > ret = -ENOIOCTLCMD;
> > break;
> > }
> > - mutex_unlock(&aac_mutex);
> > return ret;
> > }
> >
> > static int aac_compat_ioctl(struct scsi_device *sdev, int cmd, void __user
> *arg)
> > {
> > - struct aac_dev *dev = (struct aac_dev *)sdev->host->hostdata;
> > + int ret;
> > + struct aac_dev *aac = (struct aac_dev *)sdev->host->hostdata;
> > +
> > if (!capable(CAP_SYS_RAWIO))
> > return -EPERM;
> > - return aac_compat_do_ioctl(dev, cmd, (unsigned long)arg);
> > +
> > + mutex_lock(&aac->ioctl_mutex);
> > + ret = aac_compat_do_ioctl(aac, cmd, (unsigned long)arg);
> > + mutex_unlock(&aac->ioctl_mutex);
> > +
> > + return ret;
> > }
> >
> > static long aac_compat_cfg_ioctl(struct file *file, unsigned cmd, unsigned
> long arg)
> > {
> > + int ret;
> > + struct aac_dev *aac = (struct aac_dev *)file->private_data;
> > +
> > if (!capable(CAP_SYS_RAWIO))
> > return -EPERM;
> > - return aac_compat_do_ioctl(file->private_data, cmd, arg);
> > +
> > + mutex_lock(&aac->ioctl_mutex);
> > + ret = aac_compat_do_ioctl(aac, cmd, arg);
> > + mutex_unlock(&aac->ioctl_mutex);
> > +
> > + return ret;
> > }
> > #endif
> >
> > @@ -1078,6 +1103,8 @@ 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 +1116,7 @@ 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 ||
> > @@ -1193,7 +1220,7 @@ static int aac_probe_one(struct pci_dev *pdev,
> const struct pci_device_id *id)
> > if (!aac->fibs)
> > goto out_free_host;
> > spin_lock_init(&aac->fib_lock);
> > -
> > + mutex_init(&aac->ioctl_mutex);
> > /*
> > * Map in the registers from the adapter.
> > */
> > @@ -1474,7 +1501,10 @@ 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
> > */
> > + mutex_lock(&aac->ioctl_mutex);
> > aac->adapter_shutdown = 0;
> > + mutex_unlock(&aac->ioctl_mutex);
>
> A mutex surrounding adapter_shutdown = 0; is needless.

Will Remove

> > +
> > scsi_unblock_requests(shost);
> >
> > return 0;
> > @@ -1633,7 +1663,10 @@ 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
> > */
> > + mutex_lock(&aac->ioctl_mutex);
> > aac->adapter_shutdown = 0;
> > + mutex_unlock(&aac->ioctl_mutex);
>
> Same here.

Will Remove

>
> aac_compat_do_ioctl and aac_do_ioctl is surrounded by mutexes - that is
> fine,
> but by moving the mutex down to aac_do_ioctl the code would be easier
> and more readable.
>
> With the new mutex, you have changed the functionality so that a new patch
> is needed for that - before this patch there was no mutex in the main
> .ioctl path.
>
> I have found no functional issues so regardless whether you follow
> my comments now, later or never -
>
> Reviewed-by: Tomas Henzl <thenzl@redhat.com>
>
> Cheers
> Tomas

I will make the changes that you have suggested ,
Create a new patch for the new mutex and apply this patch on top of it.

Thank you Tomas.

Regards,
Raghava Aditya

>
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> > +
> > aac->handle_pci_error = 0;
> >
> > shost_for_each_device(sdev, shost)