Hey Baokun, thanks for the v2.
On Thu, Feb 01, 2024 at 10:18:45PM +0800, Baokun Li wrote:
> When yangerkun review commit 93cdf49f6eca ("ext4: Fix best extent lstart
> adjustment logic in ext4_mb_new_inode_pa()"), it was found that the best
> extent did not completely cover the original request after adjusting the
> best extent lstart in ext4_mb_new_inode_pa() as follows:
>
> original request: 2/10(8)
> normalized request: 0/64(64)
> best extent: 0/9(9)
>
> When we check if best ex can be kept at start of goal, ac_o_ex.fe_logical
> is 2 less than the adjusted best extent logical end 9, so we think the
> adjustment is done. But obviously 0/9(9) doesn't cover 2/10(8), so we
> should determine here if the original request logical end is less than or
> equal to the adjusted best extent logical end.
>
> In addition, add a comment stating when adjusted best_ex will not cover
> the original request, and remove the duplicate assertion because adjusting
> lstart makes no change to b_ex.fe_len.
>
> Link: https://lore.kernel.org/r/3630fa7f-b432-7afd-5f79-781bc3b2c5ea@xxxxxxxxxx
> Fixes: 93cdf49f6eca ("ext4: Fix best extent lstart adjustment logic in ext4_mb_new_inode_pa()")
> Cc: stable@xxxxxxxxxx
So I'm not sure if this is actually fixing a BUG and if we need to
backport this to stable but I guess Ted can take a call on that.
Other than that, the patch looks good. Feel free to add:
Reviewed-by: Ojaswin Mujoo <ojaswin@xxxxxxxxxxxxx>
Regards,
ojaswin
> Signed-off-by: yangerkun <yangerkun@xxxxxxxxxx>
> Signed-off-by: Baokun Li <libaokun1@xxxxxxxxxx>
