On 9/2/25 6:00 PM, Yu Kuai wrote:
Hi,
在 2025/09/03 1:20, Bart Van Assche 写道:
On 8/31/25 8:32 PM, Yu Kuai wrote:
-void submit_bio_noacct_nocheck(struct bio *bio)
+void submit_bio_noacct_nocheck(struct bio *bio, bool split)
{
blk_cgroup_bio_start(bio);
blkcg_bio_issue_init(bio);
@@ -745,12 +745,16 @@ void submit_bio_noacct_nocheck(struct bio *bio)
* to collect a list of requests submited by a ->submit_bio
method while
* it is active, and then process them after it returned.
*/
- if (current->bio_list)
- bio_list_add(¤t->bio_list[0], bio);
- else if (!bdev_test_flag(bio->bi_bdev, BD_HAS_SUBMIT_BIO))
+ if (current->bio_list) {
+ if (split && !bdev_is_zoned(bio->bi_bdev))
+ bio_list_add_head(¤t->bio_list[0], bio);
+ else
+ bio_list_add(¤t->bio_list[0], bio);
The above change will cause write errors for zoned block devices. As I
have shown before, also for zoned block devices, if a bio is split
insertion must happen at the head of the list. See e.g.
"Re: [PATCH 1/2] block: Make __submit_bio_noacct() preserve the bio
submission order"
(https://lore.kernel.org/linux-block/a0c89df8-4b33-409c-ba43-
f9543fb1b091@xxxxxxx/)
Do you mean we should remove the bdev_is_zoned() checking? I added this
checking because I'm not quite sure about details in zone device, and
this checking is aimed at prevent functional changes in zone device.
Yes, the bdev_is_zoned() check should be removed. I spent a significant
amount of time on root-causing and proposing fixes for write errors
caused by recursive bio splitting for zoned devices. What I learned by
analyzing these write errors is the basis for this feedback.
So I don't think this change will cause write errors, the write errors
should already exist before this set, right?
Agreed. Although I haven't checked this yet, if the bdev_is_zoned()
check is removed from this patch, this patch should fix the write errors
triggered by stacking a dm driver on top of a zoned block device if
inline encryption is enabled.
Thanks,
Bart.
