Re: [PATCH 2/7] block: merge invalidate_partitions into rescan_partitions

Eric Biggers
2019-11-30T21:49:44Z

Hi Christoph,

On Thu, Nov 14, 2019 at 03:34:33PM +0100, Christoph Hellwig wrote:
> A lot of the logic in invalidate_partitions and rescan_partitions is
> shared. Merge the two functions to simplify things. There is a small
> behavior change in that we now send the kevent change notice also if we
> were not invalidating but no partitions were found, which seems like
> the right thing to do.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> Reviewed-by: Jan Kara <jack@suse.cz>
> ---
> block/ioctl.c | 2 +-
> block/partition-generic.c | 38 ++++++++++++++------------------------
> fs/block_dev.c | 5 +----
> include/linux/genhd.h | 4 ++--
> 4 files changed, 18 insertions(+), 31 deletions(-)
>

Mainline is broken for me because systemd-udevd spins forever using max CPU
starting at boot time. I bisected it to this commit.

I'm not an expert in this code, but the following patch fixes it:

diff --git a/block/partition-generic.c b/block/partition-generic.c
index 6b9f4f5d993a..b0eebd7580ab 100644
--- a/block/partition-generic.c
+++ b/block/partition-generic.c
@@ -599,7 +599,8 @@ int rescan_partitions(struct gendisk *disk, struct block_device *bdev,
* Tell userspace that the media / partition table may have
* changed.
*/
- kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
+ if (invalidate)
+ kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
return 0;
}

Do you have any better suggestion, or should I just send this as a formal patch?

- Eric