[v2,3/7] libnvdimm/region: Register badblocks before namespaces
diff mbox series

Message ID 156341208365.292348.1547528796026249120.stgit@dwillia2-desk3.amr.corp.intel.com
State Accepted
Commit 700cd033a82d466ad8f9615f9985525e45f8960a
Headers show
Series
  • libnvdimm: Fix async operations and locking
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Commit Message

Dan Williams July 18, 2019, 1:08 a.m. UTC
Namespace activation expects to be able to reference region badblocks.
The following warning sometimes triggers when asynchronous namespace
activation races in front of the completion of namespace probing. Move
all possible namespace probing after region badblocks initialization.

Otherwise, lockdep sometimes catches the uninitialized state of the
badblocks seqlock with stack trace signatures like:

    INFO: trying to register non-static key.
    pmem2: detected capacity change from 0 to 136365211648
    the code is fine but needs lockdep annotation.
    turning off the locking correctness validator.
    CPU: 9 PID: 358 Comm: kworker/u80:5 Tainted: G           OE     5.2.0-rc4+ #3382
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015
    Workqueue: events_unbound async_run_entry_fn
    Call Trace:
     dump_stack+0x85/0xc0
    pmem1.12: detected capacity change from 0 to 8589934592
     register_lock_class+0x56a/0x570
     ? check_object+0x140/0x270
     __lock_acquire+0x80/0x1710
     ? __mutex_lock+0x39d/0x910
     lock_acquire+0x9e/0x180
     ? nd_pfn_validate+0x28f/0x440 [libnvdimm]
     badblocks_check+0x93/0x1f0
     ? nd_pfn_validate+0x28f/0x440 [libnvdimm]
     nd_pfn_validate+0x28f/0x440 [libnvdimm]
     ? lockdep_hardirqs_on+0xf0/0x180
     nd_dax_probe+0x9a/0x120 [libnvdimm]
     nd_pmem_probe+0x6d/0x180 [nd_pmem]
     nvdimm_bus_probe+0x90/0x2c0 [libnvdimm]

Fixes: 48af2f7e52f4 ("libnvdimm, pfn: during init, clear errors...")
Cc: <stable@vger.kernel.org>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 drivers/nvdimm/region.c |   22 +++++++++++-----------
 1 file changed, 11 insertions(+), 11 deletions(-)

Comments

Vishal Verma July 18, 2019, 6:16 p.m. UTC | #1
On Wed, 2019-07-17 at 18:08 -0700, Dan Williams wrote:
> Namespace activation expects to be able to reference region badblocks.
> The following warning sometimes triggers when asynchronous namespace
> activation races in front of the completion of namespace probing. Move
> all possible namespace probing after region badblocks initialization.
> 
> Otherwise, lockdep sometimes catches the uninitialized state of the
> badblocks seqlock with stack trace signatures like:
> 
>     INFO: trying to register non-static key.
>     pmem2: detected capacity change from 0 to 136365211648
>     the code is fine but needs lockdep annotation.
>     turning off the locking correctness validator.
>     CPU: 9 PID: 358 Comm: kworker/u80:5 Tainted:
> G           OE     5.2.0-rc4+ #3382
>     Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.0.0
> 02/06/2015
>     Workqueue: events_unbound async_run_entry_fn
>     Call Trace:
>      dump_stack+0x85/0xc0
>     pmem1.12: detected capacity change from 0 to 8589934592
>      register_lock_class+0x56a/0x570
>      ? check_object+0x140/0x270
>      __lock_acquire+0x80/0x1710
>      ? __mutex_lock+0x39d/0x910
>      lock_acquire+0x9e/0x180
>      ? nd_pfn_validate+0x28f/0x440 [libnvdimm]
>      badblocks_check+0x93/0x1f0
>      ? nd_pfn_validate+0x28f/0x440 [libnvdimm]
>      nd_pfn_validate+0x28f/0x440 [libnvdimm]
>      ? lockdep_hardirqs_on+0xf0/0x180
>      nd_dax_probe+0x9a/0x120 [libnvdimm]
>      nd_pmem_probe+0x6d/0x180 [nd_pmem]
>      nvdimm_bus_probe+0x90/0x2c0 [libnvdimm]
> 
> Fixes: 48af2f7e52f4 ("libnvdimm, pfn: during init, clear errors...")
> Cc: <stable@vger.kernel.org>
> Cc: Vishal Verma <vishal.l.verma@intel.com>
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
> ---
>  drivers/nvdimm/region.c |   22 +++++++++++-----------
>  1 file changed, 11 insertions(+), 11 deletions(-)

This looks good to me,
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>

> 
> diff --git a/drivers/nvdimm/region.c b/drivers/nvdimm/region.c
> index ef46cc3a71ae..488c47ac4c4a 100644
> --- a/drivers/nvdimm/region.c
> +++ b/drivers/nvdimm/region.c
> @@ -34,17 +34,6 @@ static int nd_region_probe(struct device *dev)
>  	if (rc)
>  		return rc;
>  
> -	rc = nd_region_register_namespaces(nd_region, &err);
> -	if (rc < 0)
> -		return rc;
> -
> -	ndrd = dev_get_drvdata(dev);
> -	ndrd->ns_active = rc;
> -	ndrd->ns_count = rc + err;
> -
> -	if (rc && err && rc == err)
> -		return -ENODEV;
> -
>  	if (is_nd_pmem(&nd_region->dev)) {
>  		struct resource ndr_res;
>  
> @@ -60,6 +49,17 @@ static int nd_region_probe(struct device *dev)
>  		nvdimm_badblocks_populate(nd_region, &nd_region->bb,
> &ndr_res);
>  	}
>  
> +	rc = nd_region_register_namespaces(nd_region, &err);
> +	if (rc < 0)
> +		return rc;
> +
> +	ndrd = dev_get_drvdata(dev);
> +	ndrd->ns_active = rc;
> +	ndrd->ns_count = rc + err;
> +
> +	if (rc && err && rc == err)
> +		return -ENODEV;
> +
>  	nd_region->btt_seed = nd_btt_create(nd_region);
>  	nd_region->pfn_seed = nd_pfn_create(nd_region);
>  	nd_region->dax_seed = nd_dax_create(nd_region);
>

Patch
diff mbox series

diff --git a/drivers/nvdimm/region.c b/drivers/nvdimm/region.c
index ef46cc3a71ae..488c47ac4c4a 100644
--- a/drivers/nvdimm/region.c
+++ b/drivers/nvdimm/region.c
@@ -34,17 +34,6 @@  static int nd_region_probe(struct device *dev)
 	if (rc)
 		return rc;
 
-	rc = nd_region_register_namespaces(nd_region, &err);
-	if (rc < 0)
-		return rc;
-
-	ndrd = dev_get_drvdata(dev);
-	ndrd->ns_active = rc;
-	ndrd->ns_count = rc + err;
-
-	if (rc && err && rc == err)
-		return -ENODEV;
-
 	if (is_nd_pmem(&nd_region->dev)) {
 		struct resource ndr_res;
 
@@ -60,6 +49,17 @@  static int nd_region_probe(struct device *dev)
 		nvdimm_badblocks_populate(nd_region, &nd_region->bb, &ndr_res);
 	}
 
+	rc = nd_region_register_namespaces(nd_region, &err);
+	if (rc < 0)
+		return rc;
+
+	ndrd = dev_get_drvdata(dev);
+	ndrd->ns_active = rc;
+	ndrd->ns_count = rc + err;
+
+	if (rc && err && rc == err)
+		return -ENODEV;
+
 	nd_region->btt_seed = nd_btt_create(nd_region);
 	nd_region->pfn_seed = nd_pfn_create(nd_region);
 	nd_region->dax_seed = nd_dax_create(nd_region);