Re: FAILED: patch "[PATCH] io_uring: don't post tag CQEs on file/buffer registration" failed to apply to 6.13-stable tree

[Jens Axboe <axboe@kernel.dk>]

[-- Attachment #1: Type: text/plain, Size: 493 bytes --]

On 4/17/25 4:47 AM, gregkh@linuxfoundation.org wrote:
> 
> The patch below does not apply to the 6.13-stable tree.
> If someone wants it applied there, or to any other stable or longterm
> tree, then please email the backport, including the original git commit
> id to <stable@vger.kernel.org>.
> 
> To reproduce the conflict and resubmit, you may use the following commands:

This one will apply to both the 6.13 and 6.14 stable branches, can
you pick it up for both? Thanks!

-- 
Jens Axboe

[-- Attachment #2: 0001-io_uring-don-t-post-tag-CQEs-on-file-buffer-registra.patch --]
[-- Type: text/x-patch, Size: 2087 bytes --]

From dd48da6de203d67a3f9db2c6b5ec5dac0702ae25 Mon Sep 17 00:00:00 2001
From: Pavel Begunkov <asml.silence@gmail.com>
Date: Fri, 4 Apr 2025 15:46:34 +0100
Subject: [PATCH] io_uring: don't post tag CQEs on file/buffer registration
 failure

Commit ab6005f3912fff07330297aba08922d2456dcede upstream.

Buffer / file table registration is all or nothing, if it fails all
resources we might have partially registered are dropped and the table
is killed. If that happens, it doesn't make sense to post any rsrc tag
CQEs. That would be confusing to the application, which should not need
to handle that case.

Cc: stable@vger.kernel.org
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Fixes: 7029acd8a9503 ("io_uring/rsrc: get rid of per-ring io_rsrc_node list")
Link: https://lore.kernel.org/r/c514446a8dcb0197cddd5d4ba8f6511da081cf1f.1743777957.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 io_uring/rsrc.c | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/io_uring/rsrc.c b/io_uring/rsrc.c
index cc58defd88d4..d8da5ad1d36b 100644
--- a/io_uring/rsrc.c
+++ b/io_uring/rsrc.c
@@ -130,6 +130,18 @@ struct io_rsrc_node *io_rsrc_node_alloc(struct io_ring_ctx *ctx, int type)
 	return node;
 }
 
+static void io_clear_table_tags(struct io_rsrc_data *data)
+{
+	int i;
+
+	for (i = 0; i < data->nr; i++) {
+		struct io_rsrc_node *node = data->nodes[i];
+
+		if (node)
+			node->tag = 0;
+	}
+}
+
 __cold void io_rsrc_data_free(struct io_ring_ctx *ctx, struct io_rsrc_data *data)
 {
 	if (!data->nr)
@@ -541,6 +553,7 @@ int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
 	io_file_table_set_alloc_range(ctx, 0, ctx->file_table.data.nr);
 	return 0;
 fail:
+	io_clear_table_tags(&ctx->file_table.data);
 	io_sqe_files_unregister(ctx);
 	return ret;
 }
@@ -858,8 +871,10 @@ int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg,
 	}
 
 	ctx->buf_table = data;
-	if (ret)
+	if (ret) {
+		io_clear_table_tags(&ctx->buf_table);
 		io_sqe_buffers_unregister(ctx);
+	}
 	return ret;
 }
 
-- 
2.49.0