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They should be written with WRITE_ONCE() to guarantee atomic stores and prevent tearing or other unsafe compiler optimizations. Fixes: ae98dbf43d75 ("io_uring/kbuf: add support for incremental buffer consumption") Signed-off-by: Joanne Koong Cc: Caleb Sander Mateos --- io_uring/kbuf.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/io_uring/kbuf.c b/io_uring/kbuf.c index 52b636d00a6b..796d131107dd 100644 --- a/io_uring/kbuf.c +++ b/io_uring/kbuf.c @@ -44,11 +44,11 @@ static bool io_kbuf_inc_commit(struct io_buffer_list *bl, int len) buf_len -= this_len; /* Stop looping for invalid buffer length of 0 */ if (buf_len || !this_len) { - buf->addr = READ_ONCE(buf->addr) + this_len; - buf->len = buf_len; + WRITE_ONCE(buf->addr, READ_ONCE(buf->addr) + this_len); + WRITE_ONCE(buf->len, buf_len); return false; } - buf->len = 0; + WRITE_ONCE(buf->len, 0); bl->head++; len -= this_len; } @@ -291,7 +291,7 @@ static int io_ring_buffers_peek(struct io_kiocb *req, struct buf_sel_arg *arg, arg->partial_map = 1; if (iov != arg->iovs) break; - buf->len = len; + WRITE_ONCE(buf->len, len); } } -- 2.47.3