/* * cpu_rmap.c: CPU affinity reverse-map support * Copyright 2011 Solarflare Communications Inc. * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 as published * by the Free Software Foundation, incorporated herein by reference. */ #include #include #include /* * These functions maintain a mapping from CPUs to some ordered set of * objects with CPU affinities. This can be seen as a reverse-map of * CPU affinity. However, we do not assume that the object affinities * cover all CPUs in the system. For those CPUs not directly covered * by object affinities, we attempt to find a nearest object based on * CPU topology. */ /** * alloc_cpu_rmap - allocate CPU affinity reverse-map * @size: Number of objects to be mapped * @flags: Allocation flags e.g. %GFP_KERNEL */ struct cpu_rmap *alloc_cpu_rmap(unsigned int size, gfp_t flags) { struct cpu_rmap *rmap; unsigned int cpu; size_t obj_offset; /* This is a silly number of objects, and we use u16 indices. */ if (size > 0xffff) return NULL; /* Offset of object pointer array from base structure */ obj_offset = ALIGN(offsetof(struct cpu_rmap, near[nr_cpu_ids]), sizeof(void *)); rmap = kzalloc(obj_offset + size * sizeof(rmap->obj[0]), flags); if (!rmap) return NULL; kref_init(&rmap->refcount); rmap->obj = (void **)((char *)rmap + obj_offset); /* Initially assign CPUs to objects on a rota, since we have * no idea where the objects are. Use infinite distance, so * any object with known distance is preferable. Include the * CPUs that are not present/online, since we definitely want * any newly-hotplugged CPUs to have some object assigned. */ for_each_possible_cpu(cpu) { rmap->near[cpu].index = cpu % size; rmap->near[cpu].dist = CPU_RMAP_DIST_INF; } rmap->size = size; return rmap; } EXPORT_SYMBOL(alloc_cpu_rmap); /** * cpu_rmap_release - internal reclaiming helper called from kref_put * @ref: kref to struct cpu_rmap */ static void cpu_rmap_release(struct kref *ref) { struct cpu_rmap *rmap = container_of(ref, struct cpu_rmap, refcount); kfree(rmap); } /** * cpu_rmap_get - internal helper to get new ref on a cpu_rmap * @rmap: reverse-map allocated with alloc_cpu_rmap() */ static inline void cpu_rmap_get(struct cpu_rmap *rmap) { kref_get(&rmap->refcount); } /** * cpu_rmap_put - release ref on a cpu_rmap * @rmap: reverse-map allocated with alloc_cpu_rmap() */ int cpu_rmap_put(struct cpu_rmap *rmap) { return kref_put(&rmap->refcount, cpu_rmap_release); } EXPORT_SYMBOL(cpu_rmap_put); /* Reevaluate nearest object for given CPU, comparing with the given * neighbours at the given distance. */ static bool cpu_rmap_copy_neigh(struct cpu_rmap *rmap, unsigned int cpu, const struct cpumask *mask, u16 dist) { int neigh; for_each_cpu(neigh, mask) { if (rmap->near[cpu].dist > dist && rmap->near[neigh].dist <= dist) { rmap->near[cpu].index = rmap->near[neigh].index; rmap->near[cpu].dist = dist; return true; } } return false; } #ifdef DEBUG static void debug_print_rmap(const struct cpu_rmap *rmap, const char *prefix) { unsigned index; unsigned int cpu; pr_info("cpu_rmap %p, %s:\n", rmap, prefix); for_each_possible_cpu(cpu) { index = rmap->near[cpu].index; pr_info("cpu %d -> obj %u (distance %u)\n", cpu, index, rmap->near[cpu].dist); } } #else static inline void debug_print_rmap(const struct cpu_rmap *rmap, const char *prefix) { } #endif /** * cpu_rmap_add - add object to a rmap * @rmap: CPU rmap allocated with alloc_cpu_rmap() * @obj: Object to add to rmap * * Return index of object. */ int cpu_rmap_add(struct cpu_rmap *rmap, void *obj) { u16 index; BUG_ON(rmap->used >= rmap->size); index = rmap->used++; rmap->obj[index] = obj; return index; } EXPORT_SYMBOL(cpu_rmap_add); /** * cpu_rmap_update - update CPU rmap following a change of object affinity * @rmap: CPU rmap to update * @index: Index of object whose affinity changed * @affinity: New CPU affinity of object */ int cpu_rmap_update(struct cpu_rmap *rmap, u16 index, const struct cpumask *affinity) { cpumask_var_t update_mask; unsigned int cpu; if (unlikely(!zalloc_cpumask_var(&update_mask, GFP_KERNEL))) return -ENOMEM; /* Invalidate distance for all CPUs for which this used to be * the nearest object. Mark those CPUs for update. */ for_each_online_cpu(cpu) { if (rmap->near[cpu].index == index) { rmap->near[cpu].dist = CPU_RMAP_DIST_INF; cpumask_set_cpu(cpu, update_mask); } } debug_print_rmap(rmap, "after invalidating old distances"); /* Set distance to 0 for all CPUs in the new affinity mask. * Mark all CPUs within their NUMA nodes for update. */ for_each_cpu(cpu, affinity) { rmap->near[cpu].index = index; rmap->near[cpu].dist = 0; cpumask_or(update_mask, update_mask, cpumask_of_node(cpu_to_node(cpu))); } debug_print_rmap(rmap, "after updating neighbours"); /* Update distances based on topology */ for_each_cpu(cpu, update_mask) { if (cpu_rmap_copy_neigh(rmap, cpu, topology_sibling_cpumask(cpu), 1)) continue; if (cpu_rmap_copy_neigh(rmap, cpu, topology_core_cpumask(cpu), 2)) continue; if (cpu_rmap_copy_neigh(rmap, cpu, cpumask_of_node(cpu_to_node(cpu)), 3)) continue; /* We could continue into NUMA node distances, but for now * we give up. */ } debug_print_rmap(rmap, "after copying neighbours"); free_cpumask_var(update_mask); return 0; } EXPORT_SYMBOL(cpu_rmap_update); /* Glue between IRQ affinity notifiers and CPU rmaps */ struct irq_glue { struct irq_affinity_notify notify; struct cpu_rmap *rmap; u16 index; }; /** * free_irq_cpu_rmap - free a CPU affinity reverse-map used for IRQs * @rmap: Reverse-map allocated with alloc_irq_cpu_map(), or %NULL * * Must be called in process context, before freeing the IRQs. */ void free_irq_cpu_rmap(struct cpu_rmap *rmap) { struct irq_glue *glue; u16 index; if (!rmap) return; for (index = 0; index < rmap->used; index++) { glue = rmap->obj[index]; irq_set_affinity_notifier(glue->notify.irq, NULL); } cpu_rmap_put(rmap); } EXPORT_SYMBOL(free_irq_cpu_rmap); /** * irq_cpu_rmap_notify - callback for IRQ subsystem when IRQ affinity updated * @notify: struct irq_affinity_notify passed by irq/manage.c * @mask: cpu mask for new SMP affinity * * This is executed in workqueue context. */ static void irq_cpu_rmap_notify(struct irq_affinity_notify *notify, const cpumask_t *mask) { struct irq_glue *glue = container_of(notify, struct irq_glue, notify); int rc; rc = cpu_rmap_update(glue->rmap, glue->index, mask); if (rc) pr_warning("irq_cpu_rmap_notify: update failed: %d\n", rc); } /** * irq_cpu_rmap_release - reclaiming callback for IRQ subsystem * @ref: kref to struct irq_affinity_notify passed by irq/manage.c */ static void irq_cpu_rmap_release(struct kref *ref) { struct irq_glue *glue = container_of(ref, struct irq_glue, notify.kref); cpu_rmap_put(glue->rmap); kfree(glue); } /** * irq_cpu_rmap_add - add an IRQ to a CPU affinity reverse-map * @rmap: The reverse-map * @irq: The IRQ number * * This adds an IRQ affinity notifier that will update the reverse-map * automatically. * * Must be called in process context, after the IRQ is allocated but * before it is bound with request_irq(). */ int irq_cpu_rmap_add(struct cpu_rmap *rmap, int irq) { struct irq_glue *glue = kzalloc(sizeof(*glue), GFP_KERNEL); int rc; if (!glue) return -ENOMEM; glue->notify.notify = irq_cpu_rmap_notify; glue->notify.release = irq_cpu_rmap_release; glue->rmap = rmap; cpu_rmap_get(rmap); glue->index = cpu_rmap_add(rmap, glue); rc = irq_set_affinity_notifier(irq, &glue->notify); if (rc) { cpu_rmap_put(glue->rmap); kfree(glue); } return rc; } EXPORT_SYMBOL(irq_cpu_rmap_add); on fw_load_abort() before accessing buf->fw_st, however there is a logical issue in having a state machine used for the fallback mechanism and preventing access from it once we abort as its inside the buf (buf->fw_st). The firmware_class.c code is setting the buf to NULL to annotate an abort has occurred. Replace this mechanism by simply using the state check instead. All the other code in place already uses similar checks for aborting as well so no further changes are needed. An oops can be reproduced with the new fw_fallback.sh fallback mechanism cancellation test. Either cancelling the fallback mechanism or the custom fallback mechanism triggers a crash. mcgrof@piggy ~/linux-next/tools/testing/selftests/firmware (git::20170111-fw-fixes)$ sudo ./fw_fallback.sh ./fw_fallback.sh: timeout works ./fw_fallback.sh: firmware comparison works ./fw_fallback.sh: fallback mechanism works [ this then sits here when it is trying the cancellation test ] Kernel log: test_firmware: loading 'nope-test-firmware.bin' misc test_firmware: Direct firmware load for nope-test-firmware.bin failed with error -2 misc test_firmware: Falling back to user helper BUG: unable to handle kernel NULL pointer dereference at 0000000000000038 IP: _request_firmware+0xa27/0xad0 PGD 0 Oops: 0000 [#1] SMP Modules linked in: test_firmware(E) ... etc ... CPU: 1 PID: 1396 Comm: fw_fallback.sh Tainted: G W E 4.10.0-rc3-next-20170111+ #30 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.10.1-0-g8891697-prebuilt.qemu-project.org 04/01/2014 task: ffff9740b27f4340 task.stack: ffffbb15c0bc8000 RIP: 0010:_request_firmware+0xa27/0xad0 RSP: 0018:ffffbb15c0bcbd10 EFLAGS: 00010246 RAX: 00000000fffffffe RBX: ffff9740afe5aa80 RCX: 0000000000000000 RDX: ffff9740b27f4340 RSI: 0000000000000283 RDI: 0000000000000000 RBP: ffffbb15c0bcbd90 R08: ffffbb15c0bcbcd8 R09: 0000000000000000 R10: 0000000894a0d4b1 R11: 000000000000008c R12: ffffffffc0312480 R13: 0000000000000005 R14: ffff9740b1c32400 R15: 00000000000003e8 FS: 00007f8604422700(0000) GS:ffff9740bfc80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000038 CR3: 000000012164c000 CR4: 00000000000006e0 Call Trace: request_firmware+0x37/0x50 trigger_request_store+0x79/0xd0 [test_firmware] dev_attr_store+0x18/0x30 sysfs_kf_write+0x37/0x40 kernfs_fop_write+0x110/0x1a0 __vfs_write+0x37/0x160 ? _cond_resched+0x1a/0x50 vfs_write+0xb5/0x1a0 SyS_write+0x55/0xc0 ? trace_do_page_fault+0x37/0xd0 entry_SYSCALL_64_fastpath+0x1e/0xad RIP: 0033:0x7f8603f49620 RSP: 002b:00007fff6287b788 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000055c307b110a0 RCX: 00007f8603f49620 RDX: 0000000000000016 RSI: 000055c3084d8a90 RDI: 0000000000000001 RBP: 0000000000000016 R08: 000000000000c0ff R09: 000055c3084d6336 R10: 000055c307b108b0 R11: 0000000000000246 R12: 000055c307b13c80 R13: 000055c3084d6320 R14: 0000000000000000 R15: 00007fff6287b950 Code: 9f 64 84 e8 9c 61 fe ff b8 f4 ff ff ff e9 6b f9 ff ff 48 c7 c7 40 6b 8d 84 89 45 a8 e8 43 84 18 00 49 8b be 00 03 00 00 8b 45 a8 <83> 7f 38 02 74 08 e8 6e ec ff ff 8b 45 a8 49 c7 86 00 03 00 00 RIP: _request_firmware+0xa27/0xad0 RSP: ffffbb15c0bcbd10 CR2: 0000000000000038 ---[ end trace 6d94ac339c133e6f ]--- Fixes: 5d47ec02c37e ("firmware: Correct handling of fw_state_wait() return value") Reported-and-Tested-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reported-and-Tested-by: Patrick Bruenn <p.bruenn@beckhoff.com> Reported-by: Chris Wilson <chris@chris-wilson.co.uk> CC: <stable@vger.kernel.org> [3.10+] Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net/bluetooth/mgmt.c')