Message ID | 20201202005222.5477-1-aik@ozlabs.ru (mailing list archive) |
---|---|
State | Accepted |
Commit | 450be4960a0fb89b931a6bb3c3f0bb538ac4c03c |
Headers | show |
Series | [kernel,v3] powerpc/pci: Remove LSI mappings on device teardown | expand |
Context | Check | Description |
---|---|---|
snowpatch_ozlabs/apply_patch | success | Successfully applied on branch powerpc/merge (78c312324391ee996944e1196123b0060888e189) |
snowpatch_ozlabs/build-ppc64le | success | Build succeeded |
snowpatch_ozlabs/build-ppc64be | success | Build succeeded |
snowpatch_ozlabs/build-ppc64e | success | Build succeeded |
snowpatch_ozlabs/build-pmac32 | success | Build succeeded |
snowpatch_ozlabs/checkpatch | warning | total: 0 errors, 0 warnings, 2 checks, 116 lines checked |
snowpatch_ozlabs/needsstable | success | Patch has no Fixes tags |
On 02/12/2020 01:52, Alexey Kardashevskiy wrote: > From: Oliver O'Halloran <oohall@gmail.com> > > When a passthrough IO adapter is removed from a pseries machine using hash > MMU and the XIVE interrupt mode, the POWER hypervisor expects the guest OS > to clear all page table entries related to the adapter. If some are still > present, the RTAS call which isolates the PCI slot returns error 9001 > "valid outstanding translations" and the removal of the IO adapter fails. > This is because when the PHBs are scanned, Linux maps automatically the > INTx interrupts in the Linux interrupt number space but these are never > removed. > > This problem can be fixed by adding the corresponding unmap operation when > the device is removed. There's no pcibios_* hook for the remove case, but > the same effect can be achieved using a bus notifier. > > Because INTx are shared among PHBs (and potentially across the system), > this adds tracking of virq to unmap them only when the last user is gone. > > Signed-off-by: Oliver O'Halloran <oohall@gmail.com> > [aik: added refcounter] > Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> > --- Looks ok to me. Reviewed-by: Frederic Barrat <fbarrat@linux.ibm.com> > Changes: > v3: > * free @vi on error path > > v2: > * added refcounter > --- > arch/powerpc/kernel/pci-common.c | 82 ++++++++++++++++++++++++++++++-- > 1 file changed, 78 insertions(+), 4 deletions(-) > > diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c > index be108616a721..2b555997b295 100644 > --- a/arch/powerpc/kernel/pci-common.c > +++ b/arch/powerpc/kernel/pci-common.c > @@ -353,6 +353,55 @@ struct pci_controller *pci_find_controller_for_domain(int domain_nr) > return NULL; > } > > +struct pci_intx_virq { > + int virq; > + struct kref kref; > + struct list_head list_node; > +}; > + > +static LIST_HEAD(intx_list); > +static DEFINE_MUTEX(intx_mutex); > + > +static void ppc_pci_intx_release(struct kref *kref) > +{ > + struct pci_intx_virq *vi = container_of(kref, struct pci_intx_virq, kref); > + > + list_del(&vi->list_node); > + irq_dispose_mapping(vi->virq); > + kfree(vi); > +} > + > +static int ppc_pci_unmap_irq_line(struct notifier_block *nb, > + unsigned long action, void *data) > +{ > + struct pci_dev *pdev = to_pci_dev(data); > + > + if (action == BUS_NOTIFY_DEL_DEVICE) { > + struct pci_intx_virq *vi; > + > + mutex_lock(&intx_mutex); > + list_for_each_entry(vi, &intx_list, list_node) { > + if (vi->virq == pdev->irq) { > + kref_put(&vi->kref, ppc_pci_intx_release); > + break; > + } > + } > + mutex_unlock(&intx_mutex); > + } > + > + return NOTIFY_DONE; > +} > + > +static struct notifier_block ppc_pci_unmap_irq_notifier = { > + .notifier_call = ppc_pci_unmap_irq_line, > +}; > + > +static int ppc_pci_register_irq_notifier(void) > +{ > + return bus_register_notifier(&pci_bus_type, &ppc_pci_unmap_irq_notifier); > +} > +arch_initcall(ppc_pci_register_irq_notifier); > + > /* > * Reads the interrupt pin to determine if interrupt is use by card. > * If the interrupt is used, then gets the interrupt line from the > @@ -361,6 +410,12 @@ struct pci_controller *pci_find_controller_for_domain(int domain_nr) > static int pci_read_irq_line(struct pci_dev *pci_dev) > { > int virq; > + struct pci_intx_virq *vi, *vitmp; > + > + /* Preallocate vi as rewind is complex if this fails after mapping */ > + vi = kzalloc(sizeof(struct pci_intx_virq), GFP_KERNEL); > + if (!vi) > + return -1; > > pr_debug("PCI: Try to map irq for %s...\n", pci_name(pci_dev)); > > @@ -377,12 +432,12 @@ static int pci_read_irq_line(struct pci_dev *pci_dev) > * function. > */ > if (pci_read_config_byte(pci_dev, PCI_INTERRUPT_PIN, &pin)) > - return -1; > + goto error_exit; > if (pin == 0) > - return -1; > + goto error_exit; > if (pci_read_config_byte(pci_dev, PCI_INTERRUPT_LINE, &line) || > line == 0xff || line == 0) { > - return -1; > + goto error_exit; > } > pr_debug(" No map ! Using line %d (pin %d) from PCI config\n", > line, pin); > @@ -394,14 +449,33 @@ static int pci_read_irq_line(struct pci_dev *pci_dev) > > if (!virq) { > pr_debug(" Failed to map !\n"); > - return -1; > + goto error_exit; > } > > pr_debug(" Mapped to linux irq %d\n", virq); > > pci_dev->irq = virq; > > + mutex_lock(&intx_mutex); > + list_for_each_entry(vitmp, &intx_list, list_node) { > + if (vitmp->virq == virq) { > + kref_get(&vitmp->kref); > + kfree(vi); > + vi = NULL; > + break; > + } > + } > + if (vi) { > + vi->virq = virq; > + kref_init(&vi->kref); > + list_add_tail(&vi->list_node, &intx_list); > + } > + mutex_unlock(&intx_mutex); > + > return 0; > +error_exit: > + kfree(vi); > + return -1; > } > > /* >
On 12/2/20 1:52 AM, Alexey Kardashevskiy wrote: > From: Oliver O'Halloran <oohall@gmail.com> > > When a passthrough IO adapter is removed from a pseries machine using hash > MMU and the XIVE interrupt mode, the POWER hypervisor expects the guest OS > to clear all page table entries related to the adapter. If some are still > present, the RTAS call which isolates the PCI slot returns error 9001 > "valid outstanding translations" and the removal of the IO adapter fails. > This is because when the PHBs are scanned, Linux maps automatically the > INTx interrupts in the Linux interrupt number space but these are never > removed. > > This problem can be fixed by adding the corresponding unmap operation when > the device is removed. There's no pcibios_* hook for the remove case, but > the same effect can be achieved using a bus notifier. > > Because INTx are shared among PHBs (and potentially across the system), > this adds tracking of virq to unmap them only when the last user is gone. > > Signed-off-by: Oliver O'Halloran <oohall@gmail.com> > [aik: added refcounter] > Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: Cédric Le Goater <clg@kaod.org> I did some PHB hotplug tests on a KVM guest and a LPAR using only LSIs. Tested-by: Cédric Le Goater <clg@kaod.org> Thanks Alexey, C. > --- > Changes: > v3: > * free @vi on error path > > v2: > * added refcounter > --- > arch/powerpc/kernel/pci-common.c | 82 ++++++++++++++++++++++++++++++-- > 1 file changed, 78 insertions(+), 4 deletions(-) > > diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c > index be108616a721..2b555997b295 100644 > --- a/arch/powerpc/kernel/pci-common.c > +++ b/arch/powerpc/kernel/pci-common.c > @@ -353,6 +353,55 @@ struct pci_controller *pci_find_controller_for_domain(int domain_nr) > return NULL; > } > > +struct pci_intx_virq { > + int virq; > + struct kref kref; > + struct list_head list_node; > +}; > + > +static LIST_HEAD(intx_list); > +static DEFINE_MUTEX(intx_mutex); > + > +static void ppc_pci_intx_release(struct kref *kref) > +{ > + struct pci_intx_virq *vi = container_of(kref, struct pci_intx_virq, kref); > + > + list_del(&vi->list_node); > + irq_dispose_mapping(vi->virq); > + kfree(vi); > +} > + > +static int ppc_pci_unmap_irq_line(struct notifier_block *nb, > + unsigned long action, void *data) > +{ > + struct pci_dev *pdev = to_pci_dev(data); > + > + if (action == BUS_NOTIFY_DEL_DEVICE) { > + struct pci_intx_virq *vi; > + > + mutex_lock(&intx_mutex); > + list_for_each_entry(vi, &intx_list, list_node) { > + if (vi->virq == pdev->irq) { > + kref_put(&vi->kref, ppc_pci_intx_release); > + break; > + } > + } > + mutex_unlock(&intx_mutex); > + } > + > + return NOTIFY_DONE; > +} > + > +static struct notifier_block ppc_pci_unmap_irq_notifier = { > + .notifier_call = ppc_pci_unmap_irq_line, > +}; > + > +static int ppc_pci_register_irq_notifier(void) > +{ > + return bus_register_notifier(&pci_bus_type, &ppc_pci_unmap_irq_notifier); > +} > +arch_initcall(ppc_pci_register_irq_notifier); > + > /* > * Reads the interrupt pin to determine if interrupt is use by card. > * If the interrupt is used, then gets the interrupt line from the > @@ -361,6 +410,12 @@ struct pci_controller *pci_find_controller_for_domain(int domain_nr) > static int pci_read_irq_line(struct pci_dev *pci_dev) > { > int virq; > + struct pci_intx_virq *vi, *vitmp; > + > + /* Preallocate vi as rewind is complex if this fails after mapping */ > + vi = kzalloc(sizeof(struct pci_intx_virq), GFP_KERNEL); > + if (!vi) > + return -1; > > pr_debug("PCI: Try to map irq for %s...\n", pci_name(pci_dev)); > > @@ -377,12 +432,12 @@ static int pci_read_irq_line(struct pci_dev *pci_dev) > * function. > */ > if (pci_read_config_byte(pci_dev, PCI_INTERRUPT_PIN, &pin)) > - return -1; > + goto error_exit; > if (pin == 0) > - return -1; > + goto error_exit; > if (pci_read_config_byte(pci_dev, PCI_INTERRUPT_LINE, &line) || > line == 0xff || line == 0) { > - return -1; > + goto error_exit; > } > pr_debug(" No map ! Using line %d (pin %d) from PCI config\n", > line, pin); > @@ -394,14 +449,33 @@ static int pci_read_irq_line(struct pci_dev *pci_dev) > > if (!virq) { > pr_debug(" Failed to map !\n"); > - return -1; > + goto error_exit; > } > > pr_debug(" Mapped to linux irq %d\n", virq); > > pci_dev->irq = virq; > > + mutex_lock(&intx_mutex); > + list_for_each_entry(vitmp, &intx_list, list_node) { > + if (vitmp->virq == virq) { > + kref_get(&vitmp->kref); > + kfree(vi); > + vi = NULL; > + break; > + } > + } > + if (vi) { > + vi->virq = virq; > + kref_init(&vi->kref); > + list_add_tail(&vi->list_node, &intx_list); > + } > + mutex_unlock(&intx_mutex); > + > return 0; > +error_exit: > + kfree(vi); > + return -1; > } > > /* >
On Wed, 2 Dec 2020 11:52:22 +1100, Alexey Kardashevskiy wrote: > When a passthrough IO adapter is removed from a pseries machine using hash > MMU and the XIVE interrupt mode, the POWER hypervisor expects the guest OS > to clear all page table entries related to the adapter. If some are still > present, the RTAS call which isolates the PCI slot returns error 9001 > "valid outstanding translations" and the removal of the IO adapter fails. > This is because when the PHBs are scanned, Linux maps automatically the > INTx interrupts in the Linux interrupt number space but these are never > removed. > > [...] Applied to powerpc/next. [1/1] powerpc/pci: Remove LSI mappings on device teardown https://git.kernel.org/powerpc/c/450be4960a0fb89b931a6bb3c3f0bb538ac4c03c cheers
diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c index be108616a721..2b555997b295 100644 --- a/arch/powerpc/kernel/pci-common.c +++ b/arch/powerpc/kernel/pci-common.c @@ -353,6 +353,55 @@ struct pci_controller *pci_find_controller_for_domain(int domain_nr) return NULL; } +struct pci_intx_virq { + int virq; + struct kref kref; + struct list_head list_node; +}; + +static LIST_HEAD(intx_list); +static DEFINE_MUTEX(intx_mutex); + +static void ppc_pci_intx_release(struct kref *kref) +{ + struct pci_intx_virq *vi = container_of(kref, struct pci_intx_virq, kref); + + list_del(&vi->list_node); + irq_dispose_mapping(vi->virq); + kfree(vi); +} + +static int ppc_pci_unmap_irq_line(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct pci_dev *pdev = to_pci_dev(data); + + if (action == BUS_NOTIFY_DEL_DEVICE) { + struct pci_intx_virq *vi; + + mutex_lock(&intx_mutex); + list_for_each_entry(vi, &intx_list, list_node) { + if (vi->virq == pdev->irq) { + kref_put(&vi->kref, ppc_pci_intx_release); + break; + } + } + mutex_unlock(&intx_mutex); + } + + return NOTIFY_DONE; +} + +static struct notifier_block ppc_pci_unmap_irq_notifier = { + .notifier_call = ppc_pci_unmap_irq_line, +}; + +static int ppc_pci_register_irq_notifier(void) +{ + return bus_register_notifier(&pci_bus_type, &ppc_pci_unmap_irq_notifier); +} +arch_initcall(ppc_pci_register_irq_notifier); + /* * Reads the interrupt pin to determine if interrupt is use by card. * If the interrupt is used, then gets the interrupt line from the @@ -361,6 +410,12 @@ struct pci_controller *pci_find_controller_for_domain(int domain_nr) static int pci_read_irq_line(struct pci_dev *pci_dev) { int virq; + struct pci_intx_virq *vi, *vitmp; + + /* Preallocate vi as rewind is complex if this fails after mapping */ + vi = kzalloc(sizeof(struct pci_intx_virq), GFP_KERNEL); + if (!vi) + return -1; pr_debug("PCI: Try to map irq for %s...\n", pci_name(pci_dev)); @@ -377,12 +432,12 @@ static int pci_read_irq_line(struct pci_dev *pci_dev) * function. */ if (pci_read_config_byte(pci_dev, PCI_INTERRUPT_PIN, &pin)) - return -1; + goto error_exit; if (pin == 0) - return -1; + goto error_exit; if (pci_read_config_byte(pci_dev, PCI_INTERRUPT_LINE, &line) || line == 0xff || line == 0) { - return -1; + goto error_exit; } pr_debug(" No map ! Using line %d (pin %d) from PCI config\n", line, pin); @@ -394,14 +449,33 @@ static int pci_read_irq_line(struct pci_dev *pci_dev) if (!virq) { pr_debug(" Failed to map !\n"); - return -1; + goto error_exit; } pr_debug(" Mapped to linux irq %d\n", virq); pci_dev->irq = virq; + mutex_lock(&intx_mutex); + list_for_each_entry(vitmp, &intx_list, list_node) { + if (vitmp->virq == virq) { + kref_get(&vitmp->kref); + kfree(vi); + vi = NULL; + break; + } + } + if (vi) { + vi->virq = virq; + kref_init(&vi->kref); + list_add_tail(&vi->list_node, &intx_list); + } + mutex_unlock(&intx_mutex); + return 0; +error_exit: + kfree(vi); + return -1; } /*