diff --git a/io_uring/io_uring.h b/io_uring/io_uring.h index 9d70b2cf7b1e..70b6675941ff 100644 --- a/io_uring/io_uring.h +++ b/io_uring/io_uring.h @@ -284,7 +284,14 @@ static inline bool io_sqring_full(struct io_ring_ctx *ctx) { struct io_rings *r = ctx->rings; - return READ_ONCE(r->sq.tail) - ctx->cached_sq_head == ctx->sq_entries; + /* + * SQPOLL must use the actual sqring head, as using the cached_sq_head + * is race prone if the SQPOLL thread has grabbed entries but not yet + * committed them to the ring. For !SQPOLL, this doesn't matter, but + * since this helper is just used for SQPOLL sqring waits (or POLLOUT), + * just read the actual sqring head unconditionally. + */ + return READ_ONCE(r->sq.tail) - READ_ONCE(r->sq.head) == ctx->sq_entries; } static inline unsigned int io_sqring_entries(struct io_ring_ctx *ctx) @@ -320,6 +327,7 @@ static inline int io_run_task_work(void) if (current->io_uring) { unsigned int count = 0; + __set_current_state(TASK_RUNNING); tctx_task_work_run(current->io_uring, UINT_MAX, &count); if (count) ret = true; diff --git a/io_uring/rsrc.c b/io_uring/rsrc.c index 33a3d156a85b..6f3b6de230bd 100644 --- a/io_uring/rsrc.c +++ b/io_uring/rsrc.c @@ -1176,7 +1176,8 @@ static int io_clone_buffers(struct io_ring_ctx *ctx, struct io_ring_ctx *src_ctx for (i = 0; i < nbufs; i++) { struct io_mapped_ubuf *src = src_ctx->user_bufs[i]; - refcount_inc(&src->refs); + if (src != &dummy_ubuf) + refcount_inc(&src->refs); user_bufs[i] = src; }