From: Pavel Begunkov <asml.silence@gmail.com> mainline inclusion from mainline-5.9-rc1 commit 5dbcad51f78434e782d0470b8b5fc4380700c35f category: feature bugzilla: https://bugzilla.openeuler.org/show_bug.cgi?id=27 CVE: NA --------------------------- io_sqe_buffer_unregister() uses cxt->sqo_mm for memory accounting, but io_ring_ctx_free() drops ->sqo_mm before leaving pinned_vm over-accounted. Postpone mm cleanup for when it's not needed anymore. Fixes: 309758254ea62 ("io_uring: report pinned memory usage") Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: yangerkun <yangerkun@huawei.com> Reviewed-by: zhangyi (F) <yi.zhang@huawei.com> Signed-off-by: Cheng Jian <cj.chengjian@huawei.com> --- 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 19db01bc88bd..d168cb1b051e 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -7364,12 +7364,12 @@ static void io_destroy_buffers(struct io_ring_ctx *ctx) static void io_ring_ctx_free(struct io_ring_ctx *ctx) { io_finish_async(ctx); + io_sqe_buffer_unregister(ctx); if (ctx->sqo_mm) { mmdrop(ctx->sqo_mm); ctx->sqo_mm = NULL; } - io_sqe_buffer_unregister(ctx); io_sqe_files_unregister(ctx); io_eventfd_unregister(ctx); io_destroy_buffers(ctx); -- 2.25.1