From: Jackie Liu liuyun01@kylinos.cn
mainline inclusion from mainline-5.4-rc1 commit 8776f3fa15a5cd213c4dfab7ddaf557983374ea6 category: feature bugzilla: https://bugzilla.openeuler.org/show_bug.cgi?id=27 CVE: NA ---------------------------
Sqo_thread will get sqring in batches, which will cause ctx->cached_sq_head to be added in batches. if one of these sqes is set with the DRAIN flag, then he will never get a chance to process, and finally sqo_thread will not exit.
Fixes: de0617e4671 ("io_uring: add support for marking commands as draining") Signed-off-by: Jackie Liu liuyun01@kylinos.cn Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Zhihao Cheng chengzhihao1@huawei.com 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 | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/fs/io_uring.c b/fs/io_uring.c index b721fb3dce92..a48331512bed 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -264,6 +264,7 @@ struct io_ring_ctx { struct sqe_submit { const struct io_uring_sqe *sqe; unsigned short index; + u32 sequence; bool has_user; bool needs_lock; bool needs_fixed_file; @@ -2015,7 +2016,7 @@ static int io_req_set_file(struct io_ring_ctx *ctx, const struct sqe_submit *s,
if (flags & IOSQE_IO_DRAIN) { req->flags |= REQ_F_IO_DRAIN; - req->sequence = ctx->cached_sq_head - 1; + req->sequence = s->sequence; }
if (!io_op_needs_file(s->sqe)) @@ -2223,6 +2224,7 @@ static bool io_get_sqring(struct io_ring_ctx *ctx, struct sqe_submit *s) if (head < ctx->sq_entries) { s->index = head; s->sqe = &ctx->sq_sqes[head]; + s->sequence = ctx->cached_sq_head; ctx->cached_sq_head++; return true; }