6.8-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jens Axboe <axboe@xxxxxxxxx> commit 3b80cff5a4d117c53d38ce805823084eaeffbde6 upstream. Now that xarray is being exclusively used for the buffer_list lookup, this check is no longer needed. Get rid of it and the is_ready member. Cc: stable@xxxxxxxxxxxxxxx # v6.4+ Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- io_uring/kbuf.c | 8 -------- io_uring/kbuf.h | 2 -- 2 files changed, 10 deletions(-) --- a/io_uring/kbuf.c +++ b/io_uring/kbuf.c @@ -61,7 +61,6 @@ static int io_buffer_add_list(struct io_ * always under the ->uring_lock, but the RCU lookup from mmap does. */ bl->bgid = bgid; - smp_store_release(&bl->is_ready, 1); return xa_err(xa_store(&ctx->io_bl_xa, bgid, bl, GFP_KERNEL)); } @@ -730,13 +729,6 @@ void *io_pbuf_get_address(struct io_ring if (!bl || !bl->is_mmap) return NULL; - /* - * Ensure the list is fully setup. Only strictly needed for RCU lookup - * via mmap, and in that case only for the array indexed groups. For - * the xarray lookups, it's either visible and ready, or not at all. - */ - if (!smp_load_acquire(&bl->is_ready)) - return NULL; return bl->buf_ring; } --- a/io_uring/kbuf.h +++ b/io_uring/kbuf.h @@ -29,8 +29,6 @@ struct io_buffer_list { __u8 is_mapped; /* ring mapped provided buffers, but mmap'ed by application */ __u8 is_mmap; - /* bl is visible from an RCU point of view for lookup */ - __u8 is_ready; }; struct io_buffer {