Re: [f2fs-dev] [PATCH] generic/064: allow 50 extents on F2FS after fcollapse

Chao Yu <[email protected]> Tue, 23 Jun 2026 16:46:29 +0800
Newsgroups org.kernel.vger.fstests,net.sourceforge.lists.linux-f2fs-devel
Message-ID <[email protected]>
On 6/22/26 15:04, Jan Prusakowski via Linux-f2fs-devel wrote:
> On F2FS, generic/064 fails with "extents mismatched before = 1 after =
> 50" following multiple fcollapse (collapse range) operations.
> 
> To ensure crash consistency and checkpoint integrity, F2FS forbids
> in-place SSR (Summary Standalone Replacement) overwrites on valid
> checkpointed blocks. When collapse range shifts blocks, F2FS allocates
> new data pages in LFS mode (out-of-place log writes). As a result,
> sequential collapse range calls rewrite shifted blocks at new log
> locations, intentionally leaving the file with 50 extents.
> 
> Adjust the extent verification in generic/064 to expect exactly 50
> extents on F2FS, while preserving the strict 1-extent requirement for
> all other filesystems. Data integrity continues to be verified via byte
> comparison.
> 
> Signed-off-by: Jaegeuk Kim <[email protected]>
> Signed-off-by: Jan Prusakowski <[email protected]>

Reviewed-by: Chao Yu <[email protected]>

Thanks,