| Message ID | 20170822073729.4856-1-luca@coelho.fi (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
On Tue, 2017-08-22 at 10:37 +0300, Luca Coelho wrote: > From: Luca Coelho <luciano.coelho@intel.com> > > Work queues cannot be allocated when a mutex is held because the mutex > may be in use and that would make it sleep. Doing so generates the > following splat with 4.13+: > > [ 19.513298] ====================================================== > [ 19.513429] WARNING: possible circular locking dependency detected > [ 19.513557] 4.13.0-rc5+ #6 Not tainted > [ 19.513638] ------------------------------------------------------ > [ 19.513767] cpuhp/0/12 is trying to acquire lock: > [ 19.513867] (&tz->lock){+.+.+.}, at: [<ffffffff924afebb>] thermal_zone_get_temp+0x5b/0xb0 > [ 19.514047] > [ 19.514047] but task is already holding lock: > [ 19.514166] (cpuhp_state){+.+.+.}, at: [<ffffffff91cc4baa>] cpuhp_thread_fun+0x3a/0x210 > [ 19.514338] > [ 19.514338] which lock already depends on the new lock. > > This lock dependency already existed with previous kernel versions, > but it was not detected until commit 49dfe2a67797 ("cpuhotplug: Link > lock stacks for hotplug callbacks") was introduced. > > Reported-by: David Weinehall <david.weinehall@intel.com> > Reported-by: Jiri Kosina <jikos@kernel.org> > Signed-off-by: Luca Coelho <luciano.coelho@intel.com> Jiri, did you have a chance to try this out? I'm about to ask Kalle to merge this so it gets in in time for 4.13-rc7. -- Cheers, Luca.
Luciano Coelho <luca@coelho.fi> wrote: > From: Luca Coelho <luciano.coelho@intel.com> > > Work queues cannot be allocated when a mutex is held because the mutex > may be in use and that would make it sleep. Doing so generates the > following splat with 4.13+: > > [ 19.513298] ====================================================== > [ 19.513429] WARNING: possible circular locking dependency detected > [ 19.513557] 4.13.0-rc5+ #6 Not tainted > [ 19.513638] ------------------------------------------------------ > [ 19.513767] cpuhp/0/12 is trying to acquire lock: > [ 19.513867] (&tz->lock){+.+.+.}, at: [<ffffffff924afebb>] thermal_zone_get_temp+0x5b/0xb0 > [ 19.514047] > [ 19.514047] but task is already holding lock: > [ 19.514166] (cpuhp_state){+.+.+.}, at: [<ffffffff91cc4baa>] cpuhp_thread_fun+0x3a/0x210 > [ 19.514338] > [ 19.514338] which lock already depends on the new lock. > > This lock dependency already existed with previous kernel versions, > but it was not detected until commit 49dfe2a67797 ("cpuhotplug: Link > lock stacks for hotplug callbacks") was introduced. > > Reported-by: David Weinehall <david.weinehall@intel.com> > Reported-by: Jiri Kosina <jikos@kernel.org> > Signed-off-by: Luca Coelho <luciano.coelho@intel.com> Patch applied to wireless-drivers.git, thanks. 10a54d8196d1 iwlwifi: pcie: move rx workqueue initialization to iwl_trans_pcie_alloc()
On Thu, 24 Aug 2017, Luca Coelho wrote: > > Work queues cannot be allocated when a mutex is held because the mutex > > may be in use and that would make it sleep. Doing so generates the > > following splat with 4.13+: > > > > [ 19.513298] ====================================================== > > [ 19.513429] WARNING: possible circular locking dependency detected > > [ 19.513557] 4.13.0-rc5+ #6 Not tainted > > [ 19.513638] ------------------------------------------------------ > > [ 19.513767] cpuhp/0/12 is trying to acquire lock: > > [ 19.513867] (&tz->lock){+.+.+.}, at: [<ffffffff924afebb>] thermal_zone_get_temp+0x5b/0xb0 > > [ 19.514047] > > [ 19.514047] but task is already holding lock: > > [ 19.514166] (cpuhp_state){+.+.+.}, at: [<ffffffff91cc4baa>] cpuhp_thread_fun+0x3a/0x210 > > [ 19.514338] > > [ 19.514338] which lock already depends on the new lock. > > > > This lock dependency already existed with previous kernel versions, > > but it was not detected until commit 49dfe2a67797 ("cpuhotplug: Link > > lock stacks for hotplug callbacks") was introduced. > > > > Reported-by: David Weinehall <david.weinehall@intel.com> > > Reported-by: Jiri Kosina <jikos@kernel.org> > > Signed-off-by: Luca Coelho <luciano.coelho@intel.com> > > Jiri, did you have a chance to try this out? I'm about to ask Kalle to > merge this so it gets in in time for 4.13-rc7. Sorry, I am almost completely offline for one more week (vacation), and will not have access to the affected system before that. But this indeed looks like a correct fix to me, so feel free to add Acked-by: Jiri Kosina <jkosina@suse.cz> I'll be able to provide my Tested-by: eventually only in ~10 days. Thanks,
On Thu, 2017-08-24 at 21:56 +0200, Jiri Kosina wrote: > On Thu, 24 Aug 2017, Luca Coelho wrote: > > > > Work queues cannot be allocated when a mutex is held because the mutex > > > may be in use and that would make it sleep. Doing so generates the > > > following splat with 4.13+: > > > > > > [ 19.513298] ====================================================== > > > [ 19.513429] WARNING: possible circular locking dependency detected > > > [ 19.513557] 4.13.0-rc5+ #6 Not tainted > > > [ 19.513638] ------------------------------------------------------ > > > [ 19.513767] cpuhp/0/12 is trying to acquire lock: > > > [ 19.513867] (&tz->lock){+.+.+.}, at: [<ffffffff924afebb>] thermal_zone_get_temp+0x5b/0xb0 > > > [ 19.514047] > > > [ 19.514047] but task is already holding lock: > > > [ 19.514166] (cpuhp_state){+.+.+.}, at: [<ffffffff91cc4baa>] cpuhp_thread_fun+0x3a/0x210 > > > [ 19.514338] > > > [ 19.514338] which lock already depends on the new lock. > > > > > > This lock dependency already existed with previous kernel versions, > > > but it was not detected until commit 49dfe2a67797 ("cpuhotplug: Link > > > lock stacks for hotplug callbacks") was introduced. > > > > > > Reported-by: David Weinehall <david.weinehall@intel.com> > > > Reported-by: Jiri Kosina <jikos@kernel.org> > > > Signed-off-by: Luca Coelho <luciano.coelho@intel.com> > > > > Jiri, did you have a chance to try this out? I'm about to ask Kalle to > > merge this so it gets in in time for 4.13-rc7. > > Sorry, I am almost completely offline for one more week (vacation), and > will not have access to the affected system before that. Sounds good! Enjoy! ;) > But this indeed > looks like a correct fix to me, so feel free to add > > Acked-by: Jiri Kosina <jkosina@suse.cz> > > I'll be able to provide my Tested-by: eventually only in ~10 days. Kalle already picked it up in wireless-drivers and this should make it's way to 4.13-rc7 (we hope). In any case, thanks for reporting and the help debugging it. -- Cheers, Luca.
Luca Coelho <luca@coelho.fi> writes: > On Thu, 2017-08-24 at 21:56 +0200, Jiri Kosina wrote: >> On Thu, 24 Aug 2017, Luca Coelho wrote: >> >> > > Work queues cannot be allocated when a mutex is held because the mutex >> > > may be in use and that would make it sleep. Doing so generates the >> > > following splat with 4.13+: >> > > >> > > [ 19.513298] ====================================================== >> > > [ 19.513429] WARNING: possible circular locking dependency detected >> > > [ 19.513557] 4.13.0-rc5+ #6 Not tainted >> > > [ 19.513638] ------------------------------------------------------ >> > > [ 19.513767] cpuhp/0/12 is trying to acquire lock: >> > > [ 19.513867] (&tz->lock){+.+.+.}, at: [<ffffffff924afebb>] >> > > thermal_zone_get_temp+0x5b/0xb0 >> > > [ 19.514047] >> > > [ 19.514047] but task is already holding lock: >> > > [ 19.514166] (cpuhp_state){+.+.+.}, at: [<ffffffff91cc4baa>] >> > > cpuhp_thread_fun+0x3a/0x210 >> > > [ 19.514338] >> > > [ 19.514338] which lock already depends on the new lock. >> > > >> > > This lock dependency already existed with previous kernel versions, >> > > but it was not detected until commit 49dfe2a67797 ("cpuhotplug: Link >> > > lock stacks for hotplug callbacks") was introduced. >> > > >> > > Reported-by: David Weinehall <david.weinehall@intel.com> >> > > Reported-by: Jiri Kosina <jikos@kernel.org> >> > > Signed-off-by: Luca Coelho <luciano.coelho@intel.com> >> > >> > Jiri, did you have a chance to try this out? I'm about to ask Kalle to >> > merge this so it gets in in time for 4.13-rc7. >> >> Sorry, I am almost completely offline for one more week (vacation), and >> will not have access to the affected system before that. > > Sounds good! Enjoy! ;) > > >> But this indeed >> looks like a correct fix to me, so feel free to add >> >> Acked-by: Jiri Kosina <jkosina@suse.cz> >> >> I'll be able to provide my Tested-by: eventually only in ~10 days. > > > Kalle already picked it up in wireless-drivers and this should make it's > way to 4.13-rc7 (we hope). It (10a54d8196d1) didn't make it to -rc7 but it's in net tree now and should make it to the next release on Sunday (either -rc8 or the final).
On Tue, Aug 22, 2017 at 10:37:29AM +0300, Luca Coelho wrote: > From: Luca Coelho <luciano.coelho@intel.com> > > Work queues cannot be allocated when a mutex is held because the mutex > may be in use and that would make it sleep. Doing so generates the > following splat with 4.13+: > > [ 19.513298] ====================================================== > [ 19.513429] WARNING: possible circular locking dependency detected > [ 19.513557] 4.13.0-rc5+ #6 Not tainted > [ 19.513638] ------------------------------------------------------ > [ 19.513767] cpuhp/0/12 is trying to acquire lock: > [ 19.513867] (&tz->lock){+.+.+.}, at: [<ffffffff924afebb>] thermal_zone_get_temp+0x5b/0xb0 > [ 19.514047] > [ 19.514047] but task is already holding lock: > [ 19.514166] (cpuhp_state){+.+.+.}, at: [<ffffffff91cc4baa>] cpuhp_thread_fun+0x3a/0x210 > [ 19.514338] > [ 19.514338] which lock already depends on the new lock. > > This lock dependency already existed with previous kernel versions, > but it was not detected until commit 49dfe2a67797 ("cpuhotplug: Link > lock stacks for hotplug callbacks") was introduced. > > Reported-by: David Weinehall <david.weinehall@intel.com> > Reported-by: Jiri Kosina <jikos@kernel.org> > Signed-off-by: Luca Coelho <luciano.coelho@intel.com> With this patch I no longer get the lockdep warning, and the driver seems to work just as well as before. Thanks! Tested-by: David Weinehall <david.weinehall@linux.intel.com> > --- > In v2: > - updated the commit message to a new version, with a grammar fix > and the actual commit that exposed the problem; > > drivers/net/wireless/intel/iwlwifi/pcie/internal.h | 2 ++ > drivers/net/wireless/intel/iwlwifi/pcie/rx.c | 10 +--------- > drivers/net/wireless/intel/iwlwifi/pcie/trans.c | 9 +++++++++ > 3 files changed, 12 insertions(+), 9 deletions(-) > > diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/internal.h b/drivers/net/wireless/intel/iwlwifi/pcie/internal.h > index fa315d84e98e..a1ea9ef97ed9 100644 > --- a/drivers/net/wireless/intel/iwlwifi/pcie/internal.h > +++ b/drivers/net/wireless/intel/iwlwifi/pcie/internal.h > @@ -787,6 +787,8 @@ int iwl_pci_fw_enter_d0i3(struct iwl_trans *trans); > > void iwl_pcie_enable_rx_wake(struct iwl_trans *trans, bool enable); > > +void iwl_pcie_rx_allocator_work(struct work_struct *data); > + > /* common functions that are used by gen2 transport */ > void iwl_pcie_apm_config(struct iwl_trans *trans); > int iwl_pcie_prepare_card_hw(struct iwl_trans *trans); > diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/rx.c b/drivers/net/wireless/intel/iwlwifi/pcie/rx.c > index 351c4423125a..942736d3fa75 100644 > --- a/drivers/net/wireless/intel/iwlwifi/pcie/rx.c > +++ b/drivers/net/wireless/intel/iwlwifi/pcie/rx.c > @@ -597,7 +597,7 @@ static void iwl_pcie_rx_allocator_get(struct iwl_trans *trans, > rxq->free_count += RX_CLAIM_REQ_ALLOC; > } > > -static void iwl_pcie_rx_allocator_work(struct work_struct *data) > +void iwl_pcie_rx_allocator_work(struct work_struct *data) > { > struct iwl_rb_allocator *rba_p = > container_of(data, struct iwl_rb_allocator, rx_alloc); > @@ -900,10 +900,6 @@ static int _iwl_pcie_rx_init(struct iwl_trans *trans) > return err; > } > def_rxq = trans_pcie->rxq; > - if (!rba->alloc_wq) > - rba->alloc_wq = alloc_workqueue("rb_allocator", > - WQ_HIGHPRI | WQ_UNBOUND, 1); > - INIT_WORK(&rba->rx_alloc, iwl_pcie_rx_allocator_work); > > spin_lock(&rba->lock); > atomic_set(&rba->req_pending, 0); > @@ -1017,10 +1013,6 @@ void iwl_pcie_rx_free(struct iwl_trans *trans) > } > > cancel_work_sync(&rba->rx_alloc); > - if (rba->alloc_wq) { > - destroy_workqueue(rba->alloc_wq); > - rba->alloc_wq = NULL; > - } > > iwl_pcie_free_rbs_pool(trans); > > diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c > index f95eec52508e..3927bbf04f72 100644 > --- a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c > +++ b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c > @@ -1786,6 +1786,11 @@ void iwl_trans_pcie_free(struct iwl_trans *trans) > iwl_pcie_tx_free(trans); > iwl_pcie_rx_free(trans); > > + if (trans_pcie->rba.alloc_wq) { > + destroy_workqueue(trans_pcie->rba.alloc_wq); > + trans_pcie->rba.alloc_wq = NULL; > + } > + > if (trans_pcie->msix_enabled) { > for (i = 0; i < trans_pcie->alloc_vecs; i++) { > irq_set_affinity_hint( > @@ -3169,6 +3174,10 @@ struct iwl_trans *iwl_trans_pcie_alloc(struct pci_dev *pdev, > trans_pcie->inta_mask = CSR_INI_SET_MASK; > } > > + trans_pcie->rba.alloc_wq = alloc_workqueue("rb_allocator", > + WQ_HIGHPRI | WQ_UNBOUND, 1); > + INIT_WORK(&trans_pcie->rba.rx_alloc, iwl_pcie_rx_allocator_work); > + > #ifdef CONFIG_IWLWIFI_PCIE_RTPM > trans->runtime_pm_mode = IWL_PLAT_PM_MODE_D0I3; > #else > -- > 2.14.1 >
On Wed, 2017-08-30 at 17:57 +0300, David Weinehall wrote: > On Tue, Aug 22, 2017 at 10:37:29AM +0300, Luca Coelho wrote: > > From: Luca Coelho <luciano.coelho@intel.com> > > > > Work queues cannot be allocated when a mutex is held because the mutex > > may be in use and that would make it sleep. Doing so generates the > > following splat with 4.13+: > > > > [ 19.513298] ====================================================== > > [ 19.513429] WARNING: possible circular locking dependency detected > > [ 19.513557] 4.13.0-rc5+ #6 Not tainted > > [ 19.513638] ------------------------------------------------------ > > [ 19.513767] cpuhp/0/12 is trying to acquire lock: > > [ 19.513867] (&tz->lock){+.+.+.}, at: [<ffffffff924afebb>] thermal_zone_get_temp+0x5b/0xb0 > > [ 19.514047] > > [ 19.514047] but task is already holding lock: > > [ 19.514166] (cpuhp_state){+.+.+.}, at: [<ffffffff91cc4baa>] cpuhp_thread_fun+0x3a/0x210 > > [ 19.514338] > > [ 19.514338] which lock already depends on the new lock. > > > > This lock dependency already existed with previous kernel versions, > > but it was not detected until commit 49dfe2a67797 ("cpuhotplug: Link > > lock stacks for hotplug callbacks") was introduced. > > > > Reported-by: David Weinehall <david.weinehall@intel.com> > > Reported-by: Jiri Kosina <jikos@kernel.org> > > Signed-off-by: Luca Coelho <luciano.coelho@intel.com> > > With this patch I no longer get the lockdep warning, > and the driver seems to work just as well as before. Great! Thanks for reporting and testing, David! > Thanks! > > Tested-by: David Weinehall <david.weinehall@linux.intel.com> Thanks for this too, but unfortunately it's too late to add it, since the patch is already in net tree. -- Cheers, Luca.
On Thu, 24 Aug 2017, Luca Coelho wrote: > > looks like a correct fix to me, so feel free to add > > > > Acked-by: Jiri Kosina <jkosina@suse.cz> > > > > I'll be able to provide my Tested-by: eventually only in ~10 days. > > > Kalle already picked it up in wireless-drivers and this should make it's > way to 4.13-rc7 (we hope). > > In any case, thanks for reporting and the help debugging it. I know it's pretty late for this to be added to the commit, but I don't want this to be left in the void, so for the sake of completness: Tested-by: Jiri Kosina <jkosina@suse.cz> Thanks,
On Mon, 2017-09-04 at 13:43 +0200, Jiri Kosina wrote: > On Thu, 24 Aug 2017, Luca Coelho wrote: > > > > looks like a correct fix to me, so feel free to add > > > > > > Acked-by: Jiri Kosina <jkosina@suse.cz> > > > > > > I'll be able to provide my Tested-by: eventually only in ~10 days. > > > > > > Kalle already picked it up in wireless-drivers and this should make it's > > way to 4.13-rc7 (we hope). > > > > In any case, thanks for reporting and the help debugging it. > > I know it's pretty late for this to be added to the commit, but I don't > want this to be left in the void, so for the sake of completness: > > Tested-by: Jiri Kosina <jkosina@suse.cz> Thanks, Jiri, for reporting, debugging and testing! -- Cheers, Luca.
diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/internal.h b/drivers/net/wireless/intel/iwlwifi/pcie/internal.h index fa315d84e98e..a1ea9ef97ed9 100644 --- a/drivers/net/wireless/intel/iwlwifi/pcie/internal.h +++ b/drivers/net/wireless/intel/iwlwifi/pcie/internal.h @@ -787,6 +787,8 @@ int iwl_pci_fw_enter_d0i3(struct iwl_trans *trans); void iwl_pcie_enable_rx_wake(struct iwl_trans *trans, bool enable); +void iwl_pcie_rx_allocator_work(struct work_struct *data); + /* common functions that are used by gen2 transport */ void iwl_pcie_apm_config(struct iwl_trans *trans); int iwl_pcie_prepare_card_hw(struct iwl_trans *trans); diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/rx.c b/drivers/net/wireless/intel/iwlwifi/pcie/rx.c index 351c4423125a..942736d3fa75 100644 --- a/drivers/net/wireless/intel/iwlwifi/pcie/rx.c +++ b/drivers/net/wireless/intel/iwlwifi/pcie/rx.c @@ -597,7 +597,7 @@ static void iwl_pcie_rx_allocator_get(struct iwl_trans *trans, rxq->free_count += RX_CLAIM_REQ_ALLOC; } -static void iwl_pcie_rx_allocator_work(struct work_struct *data) +void iwl_pcie_rx_allocator_work(struct work_struct *data) { struct iwl_rb_allocator *rba_p = container_of(data, struct iwl_rb_allocator, rx_alloc); @@ -900,10 +900,6 @@ static int _iwl_pcie_rx_init(struct iwl_trans *trans) return err; } def_rxq = trans_pcie->rxq; - if (!rba->alloc_wq) - rba->alloc_wq = alloc_workqueue("rb_allocator", - WQ_HIGHPRI | WQ_UNBOUND, 1); - INIT_WORK(&rba->rx_alloc, iwl_pcie_rx_allocator_work); spin_lock(&rba->lock); atomic_set(&rba->req_pending, 0); @@ -1017,10 +1013,6 @@ void iwl_pcie_rx_free(struct iwl_trans *trans) } cancel_work_sync(&rba->rx_alloc); - if (rba->alloc_wq) { - destroy_workqueue(rba->alloc_wq); - rba->alloc_wq = NULL; - } iwl_pcie_free_rbs_pool(trans); diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c index f95eec52508e..3927bbf04f72 100644 --- a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c +++ b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c @@ -1786,6 +1786,11 @@ void iwl_trans_pcie_free(struct iwl_trans *trans) iwl_pcie_tx_free(trans); iwl_pcie_rx_free(trans); + if (trans_pcie->rba.alloc_wq) { + destroy_workqueue(trans_pcie->rba.alloc_wq); + trans_pcie->rba.alloc_wq = NULL; + } + if (trans_pcie->msix_enabled) { for (i = 0; i < trans_pcie->alloc_vecs; i++) { irq_set_affinity_hint( @@ -3169,6 +3174,10 @@ struct iwl_trans *iwl_trans_pcie_alloc(struct pci_dev *pdev, trans_pcie->inta_mask = CSR_INI_SET_MASK; } + trans_pcie->rba.alloc_wq = alloc_workqueue("rb_allocator", + WQ_HIGHPRI | WQ_UNBOUND, 1); + INIT_WORK(&trans_pcie->rba.rx_alloc, iwl_pcie_rx_allocator_work); + #ifdef CONFIG_IWLWIFI_PCIE_RTPM trans->runtime_pm_mode = IWL_PLAT_PM_MODE_D0I3; #else