Messages in this thread Patch in this message | | | Date | Mon, 25 Dec 2006 17:30:23 +0900 | From | Akinobu Mita <> | Subject | Re: [PATCH -mm] ehca: avoid crash on kthread_create() failure |
| |
On Mon, Dec 25, 2006 at 05:12:57PM +0900, Akinobu Mita wrote: > Index: 2.6-mm/drivers/infiniband/hw/ehca/ehca_irq.c > =================================================================== > --- 2.6-mm.orig/drivers/infiniband/hw/ehca/ehca_irq.c > +++ 2.6-mm/drivers/infiniband/hw/ehca/ehca_irq.c > @@ -606,13 +606,16 @@ static int comp_task(void *__cct) > static struct task_struct *create_comp_task(struct ehca_comp_pool *pool, > int cpu) > { > + struct task_struct *task; > struct ehca_cpu_comp_task *cct; > > cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu); > spin_lock_init(&cct->task_lock); > INIT_LIST_HEAD(&cct->cq_list); > init_waitqueue_head(&cct->wait_queue); > - cct->task = kthread_create(comp_task, cct, "ehca_comp/%d", cpu); > + task = kthread_create(comp_task, cct, "ehca_comp/%d", cpu); > + if (!IS_ERR(task)) > + cct->task = task; > > return cct->task; > }
This patch is wrong. It changes to make create_comp_task() return NULL on failure.
(BTW, all these ehca fixes are not compile tested due to luck of cross comile environment)
Subject: [PATCH -mm] ehca: avoid crash on kthread_create() failure (v2)
This patch disallows invalid task_struct pointer returned by kthread_create() to be written to percpu data to avoid crash.
Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Hoang-Nam Nguyen <hnguyen@de.ibm.com> Cc: Christoph Raisch <raisch@de.ibm.com> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
--- drivers/infiniband/hw/ehca/ehca_irq.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-)
Index: 2.6-mm/drivers/infiniband/hw/ehca/ehca_irq.c =================================================================== --- 2.6-mm.orig/drivers/infiniband/hw/ehca/ehca_irq.c +++ 2.6-mm/drivers/infiniband/hw/ehca/ehca_irq.c @@ -606,15 +606,18 @@ static int comp_task(void *__cct) static struct task_struct *create_comp_task(struct ehca_comp_pool *pool, int cpu) { + struct task_struct *task; struct ehca_cpu_comp_task *cct; cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu); spin_lock_init(&cct->task_lock); INIT_LIST_HEAD(&cct->cq_list); init_waitqueue_head(&cct->wait_queue); - cct->task = kthread_create(comp_task, cct, "ehca_comp/%d", cpu); + task = kthread_create(comp_task, cct, "ehca_comp/%d", cpu); + if (!IS_ERR(task)) + cct->task = task; - return cct->task; + return task; } static void destroy_comp_task(struct ehca_comp_pool *pool, @@ -684,8 +687,10 @@ static int comp_pool_callback(struct not case CPU_UP_CANCELED: ehca_gen_dbg("CPU: %x (CPU_CANCELED)", cpu); cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu); - kthread_bind(cct->task, any_online_cpu(cpu_online_map)); - destroy_comp_task(pool, cpu); + if (cct->task) { + kthread_bind(cct->task, any_online_cpu(cpu_online_map)); + destroy_comp_task(pool, cpu); + } break; case CPU_ONLINE: ehca_gen_dbg("CPU: %x (CPU_ONLINE)", cpu); - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |