This is a note to let you know that I've just added the patch titled xen/events: drop xen_allocate_irqs_dynamic() to the 6.6-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: xen-events-drop-xen_allocate_irqs_dynamic.patch and it can be found in the queue-6.6 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 1c37d9d8b5ba3045652ec98bccca52987c81bf5d Author: Juergen Gross <jgross@xxxxxxxx> Date: Wed Sep 27 10:29:02 2023 +0200 xen/events: drop xen_allocate_irqs_dynamic() [ Upstream commit 5dd9ad32d7758b1a76742f394acf0eb3ac8a636a ] Instead of having a common function for allocating a single IRQ or a consecutive number of IRQs, split up the functionality into the callers of xen_allocate_irqs_dynamic(). This allows to handle any allocation error in xen_irq_init() gracefully instead of panicing the system. Let xen_irq_init() return the irq_info pointer or NULL in case of an allocation error. Additionally set the IRQ into irq_info already at allocation time, as otherwise the IRQ would be '0' (which is a valid IRQ number) until being set. Signed-off-by: Juergen Gross <jgross@xxxxxxxx> Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@xxxxxxxx> Signed-off-by: Juergen Gross <jgross@xxxxxxxx> Stable-dep-of: fa765c4b4aed ("xen/events: close evtchn after mapping cleanup") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c index d3d7501628381..4dfd68382465b 100644 --- a/drivers/xen/events/events_base.c +++ b/drivers/xen/events/events_base.c @@ -304,6 +304,13 @@ static void channels_on_cpu_inc(struct irq_info *info) info->is_accounted = 1; } +static void xen_irq_free_desc(unsigned int irq) +{ + /* Legacy IRQ descriptors are managed by the arch. */ + if (irq >= nr_legacy_irqs()) + irq_free_desc(irq); +} + static void delayed_free_irq(struct work_struct *work) { struct irq_info *info = container_of(to_rcu_work(work), struct irq_info, @@ -315,9 +322,7 @@ static void delayed_free_irq(struct work_struct *work) kfree(info); - /* Legacy IRQ descriptors are managed by the arch. */ - if (irq >= nr_legacy_irqs()) - irq_free_desc(irq); + xen_irq_free_desc(irq); } /* Constructors for packed IRQ information. */ @@ -332,7 +337,6 @@ static int xen_irq_info_common_setup(struct irq_info *info, BUG_ON(info->type != IRQT_UNBOUND && info->type != type); info->type = type; - info->irq = irq; info->evtchn = evtchn; info->cpu = cpu; info->mask_reason = EVT_MASK_REASON_EXPLICIT; @@ -733,47 +737,45 @@ void xen_irq_lateeoi(unsigned int irq, unsigned int eoi_flags) } EXPORT_SYMBOL_GPL(xen_irq_lateeoi); -static void xen_irq_init(unsigned irq) +static struct irq_info *xen_irq_init(unsigned int irq) { struct irq_info *info; info = kzalloc(sizeof(*info), GFP_KERNEL); - if (info == NULL) - panic("Unable to allocate metadata for IRQ%d\n", irq); + if (info) { + info->irq = irq; + info->type = IRQT_UNBOUND; + info->refcnt = -1; + INIT_RCU_WORK(&info->rwork, delayed_free_irq); - info->type = IRQT_UNBOUND; - info->refcnt = -1; - INIT_RCU_WORK(&info->rwork, delayed_free_irq); + set_info_for_irq(irq, info); + /* + * Interrupt affinity setting can be immediate. No point + * in delaying it until an interrupt is handled. + */ + irq_set_status_flags(irq, IRQ_MOVE_PCNTXT); - set_info_for_irq(irq, info); - /* - * Interrupt affinity setting can be immediate. No point - * in delaying it until an interrupt is handled. - */ - irq_set_status_flags(irq, IRQ_MOVE_PCNTXT); + INIT_LIST_HEAD(&info->eoi_list); + list_add_tail(&info->list, &xen_irq_list_head); + } - INIT_LIST_HEAD(&info->eoi_list); - list_add_tail(&info->list, &xen_irq_list_head); + return info; } -static int __must_check xen_allocate_irqs_dynamic(int nvec) +static inline int __must_check xen_allocate_irq_dynamic(void) { - int i, irq = irq_alloc_descs(-1, 0, nvec, -1); + int irq = irq_alloc_desc_from(0, -1); if (irq >= 0) { - for (i = 0; i < nvec; i++) - xen_irq_init(irq + i); + if (!xen_irq_init(irq)) { + xen_irq_free_desc(irq); + irq = -1; + } } return irq; } -static inline int __must_check xen_allocate_irq_dynamic(void) -{ - - return xen_allocate_irqs_dynamic(1); -} - static int __must_check xen_allocate_irq_gsi(unsigned gsi) { int irq; @@ -793,7 +795,10 @@ static int __must_check xen_allocate_irq_gsi(unsigned gsi) else irq = irq_alloc_desc_at(gsi, -1); - xen_irq_init(irq); + if (!xen_irq_init(irq)) { + xen_irq_free_desc(irq); + irq = -1; + } return irq; } @@ -963,6 +968,11 @@ static void __unbind_from_irq(unsigned int irq) evtchn_port_t evtchn = evtchn_from_irq(irq); struct irq_info *info = info_for_irq(irq); + if (!info) { + xen_irq_free_desc(irq); + return; + } + if (info->refcnt > 0) { info->refcnt--; if (info->refcnt != 0) @@ -1101,11 +1111,14 @@ int xen_bind_pirq_msi_to_irq(struct pci_dev *dev, struct msi_desc *msidesc, mutex_lock(&irq_mapping_update_lock); - irq = xen_allocate_irqs_dynamic(nvec); + irq = irq_alloc_descs(-1, 0, nvec, -1); if (irq < 0) goto out; for (i = 0; i < nvec; i++) { + if (!xen_irq_init(irq + i)) + goto error_irq; + irq_set_chip_and_handler_name(irq + i, &xen_pirq_chip, handle_edge_irq, name); ret = xen_irq_info_pirq_setup(irq + i, 0, pirq + i, 0, domid, @@ -1753,6 +1766,7 @@ void rebind_evtchn_irq(evtchn_port_t evtchn, int irq) so there should be a proper type */ BUG_ON(info->type == IRQT_UNBOUND); + info->irq = irq; (void)xen_irq_info_evtchn_setup(irq, evtchn, NULL); mutex_unlock(&irq_mapping_update_lock);