From: Jens Axboe <axboe@kernel.dk>
Date: Thu, 13 Feb 2025 15:58:17 +0000 (-0700)
Subject: t/io_uring: fix passthrough fixed buffer support
X-Git-Tag: fio-3.39~4
X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=e2d375856c5a443b340b06a33fb40740dda7fee9;p=fio.git

t/io_uring: fix passthrough fixed buffer support

A previous commit changed t/io_uring to register a single region for
all of the registered buffers, and while it updated non-passthrough IO
for that change, the passthrough path still sets a specific buffer
index. This makes passthrough with fixed buffers fail for any buffer
but the first one, as it's asking for a buffer that doesn't exist rather
than index the first one. That causes -EFAULT completions.

Ensure the buf_index is set to 0 for passthrough as well.

Fixes: 21f461f8c2b9 ("t/io_uring: register single buffer for whole IO region")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---

diff --git a/t/io_uring.c b/t/io_uring.c
index eea5fe0a..581cfe53 100644
--- a/t/io_uring.c
+++ b/t/io_uring.c
@@ -628,7 +628,7 @@ static void init_io_pt(struct submitter *s, unsigned index)
 	cmd->data_len = bs;
 	if (fixedbufs) {
 		sqe->uring_cmd_flags = IORING_URING_CMD_FIXED;
-		sqe->buf_index = index;
+		sqe->buf_index = 0;
 	}
 	cmd->nsid = f->nsid;
 	cmd->opcode = 2;