When the cxl driver creates a context, it stores the pid of the calling task, and mistakenly increments the reference count of the struct pid twice, once through get_task_pid(), once through get_pid(). The reference count is only decremented once on detach. As a result, a struct pid is leaked and it reduces the number of processes that can run simultaneously by one. The fix is to simply remove the call to get_pid(). There is a separate patch for the kernel API, since it goes to different kernel versions. Signed-off-by: Frederic Barrat <fbarrat@xxxxxxxxxxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> # 3.18+ --- drivers/misc/cxl/file.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/misc/cxl/file.c b/drivers/misc/cxl/file.c index 7ccd299..97003ee 100644 --- a/drivers/misc/cxl/file.c +++ b/drivers/misc/cxl/file.c @@ -199,7 +199,7 @@ static long afu_ioctl_start_work(struct cxl_context *ctx, * behalf of another process, so the AFU's mm gets bound to the process * that performs this ioctl and not the process that opened the file. */ - ctx->pid = get_pid(get_task_pid(current, PIDTYPE_PID)); + ctx->pid = get_task_pid(current, PIDTYPE_PID); trace_cxl_attach(ctx, work.work_element_descriptor, work.num_interrupts, amr); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html