when parent process setup a io_uring_instance, the ctx->sqo_mm was assigned of parent process'mm. Then it fork a child process. So the child process inherits the io_uring_instance fd from parent process. Then the child process submit a io task to the io_uring instance. The kworker will do the io task actually, and use the ctx->sqo_mm as its mm, but this ctx->sqo_mm is parent process's mm, not the child process's mm. so child do the io task unsuccessfully. To fix this bug, when a process submit a io task to the kworker, assign the ctx->sqo_mm with this process's mm. Signed-off-by: Yinyin Zhu <zhuyinyin@xxxxxxxxxxxxx> --- fs/io_uring.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index f115fff39cf4..f5d6bd54a625 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -514,7 +514,7 @@ static inline void io_queue_async_work(struct io_ring_ctx *ctx, } req->files = current->files; - + ctx->sqo_mm = current->mm; spin_lock_irqsave(&ctx->task_lock, flags); list_add(&req->task_list, &ctx->task_list); req->work_task = NULL; -- 2.11.0
