Re: [PATCH 6.6] Revert "dm-crypt, dm-verity: disable tasklets"

From: Li Lingfeng
Date: Thu Apr 11 2024 - 08:18:21 EST


There is no need to revert it in Linus's tree since the expanded workqueue can work like tasklet.
https://lore.kernel.org/lkml/20240130091300.2968534-1-tj@xxxxxxxxxx/

I'm not sure if the problem described in [1] could be triggered by a scenario I haven't considered. So I only send the revert patch to 6.6 mainly for comments.
Of course, I think the other branches need it too.

Thanks

在 2024/4/11 17:52, Greg KH 写道:
On Thu, Apr 11, 2024 at 05:15:39PM +0800, Li Lingfeng wrote:
This reverts commit 5735a2671ffb70ea29ca83969fe01316ee2ed6fc which is
commit 0a9bab391e336489169b95cb0d4553d921302189 upstream.

Tasklet is thought to cause memory corruption [1], so it was disabled in
dm-crypt and dm-verity. However, memory corruption may not happen since
cc->io_queue is created without WQ_UNBOUND [2].
Revert commit 5735a2671ffb ("dm-crypt, dm-verity: disable tasklets") to
bring tasklet back.

[1] https://lore.kernel.org/all/d390d7ee-f142-44d3-822a-87949e14608b@xxxxxxx/T/
[2] https://lore.kernel.org/all/4d331659-badd-749d-fba1-271543631a8a@xxxxxxxxxx/

Signed-off-by: Li Lingfeng <lilingfeng3@xxxxxxxxxx>
---
drivers/md/dm-crypt.c | 38 +++++++++++++++++++++++++++++++++--
drivers/md/dm-verity-target.c | 26 ++++++++++++++++++++++--
drivers/md/dm-verity.h | 1 +
3 files changed, 61 insertions(+), 4 deletions(-)
What is the commit id of this in Linus's tree? And why only 6.6.y?

thanks,

greg k-h