Hi Christoph, Apologies for the delay. Thanks a ton for your patch! Your patch solution works for me. I sent https://lore.kernel.org/all/20240405014253.748627-1-saranyamohan@xxxxxxxxxx/ for the block layer patch and https://lore.kernel.org/all/20240405015657.751659-1-saranyamohan@xxxxxxxxxx/ for the blktest added. Once I get confirmation that they look good, I have the changes for the older LTS which I can share. This patch doesn't cleanly apply but your idea of flagging and using that to return errors, fixes the regression for stable kernels like 5.10. Thanks again. -Saranya On Tue, Mar 19, 2024 at 6:51 PM Christoph Hellwig <hch@xxxxxx> wrote: > > Please try the patch below: > > I would also relly help to have a blktsts test case to show your > issue and verify that it is fixed. > > diff --git a/block/bdev.c b/block/bdev.c > index e7adaaf1c21927..51071d371863e0 100644 > --- a/block/bdev.c > +++ b/block/bdev.c > @@ -645,6 +645,14 @@ static void blkdev_flush_mapping(struct block_device *bdev) > bdev_write_inode(bdev); > } > > +static void blkdev_put_whole(struct block_device *bdev) > +{ > + if (atomic_dec_and_test(&bdev->bd_openers)) > + blkdev_flush_mapping(bdev); > + if (bdev->bd_disk->fops->release) > + bdev->bd_disk->fops->release(bdev->bd_disk); > +} > + > static int blkdev_get_whole(struct block_device *bdev, blk_mode_t mode) > { > struct gendisk *disk = bdev->bd_disk; > @@ -663,20 +671,21 @@ static int blkdev_get_whole(struct block_device *bdev, blk_mode_t mode) > > if (!atomic_read(&bdev->bd_openers)) > set_init_blocksize(bdev); > - if (test_bit(GD_NEED_PART_SCAN, &disk->state)) > - bdev_disk_changed(disk, false); > atomic_inc(&bdev->bd_openers); > + if (test_bit(GD_NEED_PART_SCAN, &disk->state)) { > + /* > + * Only return scanning errors if we are called from conexts > + * that explicitly want them, e.g. the BLKRRPART ioctl. > + */ > + ret = bdev_disk_changed(disk, false); > + if (ret && (mode & BLK_OPEN_STRICT_SCAN)) { > + blkdev_put_whole(bdev); > + return ret; > + } > + } > return 0; > } > > -static void blkdev_put_whole(struct block_device *bdev) > -{ > - if (atomic_dec_and_test(&bdev->bd_openers)) > - blkdev_flush_mapping(bdev); > - if (bdev->bd_disk->fops->release) > - bdev->bd_disk->fops->release(bdev->bd_disk); > -} > - > static int blkdev_get_part(struct block_device *part, blk_mode_t mode) > { > struct gendisk *disk = part->bd_disk; > diff --git a/block/ioctl.c b/block/ioctl.c > index 0c76137adcaaa5..128f503828cee7 100644 > --- a/block/ioctl.c > +++ b/block/ioctl.c > @@ -562,7 +562,8 @@ static int blkdev_common_ioctl(struct block_device *bdev, blk_mode_t mode, > return -EACCES; > if (bdev_is_partition(bdev)) > return -EINVAL; > - return disk_scan_partitions(bdev->bd_disk, mode); > + return disk_scan_partitions(bdev->bd_disk, > + mode | BLK_OPEN_STRICT_SCAN); > case BLKTRACESTART: > case BLKTRACESTOP: > case BLKTRACETEARDOWN: > diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h > index f9b87c39cab047..272ce42f297cfe 100644 > --- a/include/linux/blkdev.h > +++ b/include/linux/blkdev.h > @@ -128,6 +128,8 @@ typedef unsigned int __bitwise blk_mode_t; > #define BLK_OPEN_WRITE_IOCTL ((__force blk_mode_t)(1 << 4)) > /* open is exclusive wrt all other BLK_OPEN_WRITE opens to the device */ > #define BLK_OPEN_RESTRICT_WRITES ((__force blk_mode_t)(1 << 5)) > +/* return partition scanning errors */ > +#define BLK_OPEN_STRICT_SCAN ((__force blk_mode_t)(1 << 5)) > > struct gendisk { > /*
