I retraced my steps: * looking for the breaking commit, between 6.2 and 6.3-rc1 * I switched to checksumming the stream and the written file; this can save time, compared to decompression * I checked for lzop, pigz, and pbzip2 So, breakage. I landed on different commits: last working commit. ok: lzop, pigz, pbzip2. 16541195c6d9 cifs: Add a function to read into an iter from a socket first broken commit. lzop failed. d08089f649a0 cifs: Change the I/O paths to use an iterator rather than a page list That broken commit is right before my previous "last good" and "break". I'm seeing some inconsistencies. I'd *thought* I was careful with dtb files and .config; I might have dropped the ball occasionally, or there's something else, I don't know what, that I'm stumbling over. To check for marginal hardware, I tried another Raspberry Pi 4. I verified baseline 6.6.52 didn't work there, and stopped there. It doesn't have any cooling; it *almost certainly* would throttle for thermal reasons, but I didn't want to push it. -James On Tue, Sep 24, 2024 at 9:35 PM james young <pronoiac@xxxxxxxxx> wrote: > > On request: > * adding another cc for Steven > * I tested 6.6.52, without any extra commits: it was bad. > > -James > > On Mon, Sep 23, 2024 at 12:36 PM james young <pronoiac@xxxxxxxxx> wrote: > > > > Hey there - > > > > On Sun, Sep 22, 2024 at 4:55 PM Wang Yugui <wangyugui@xxxxxxxxxxxx> wrote: > > > > > > Hi, > > > > > > > I was benchmarking some compressors, piping to and from a network share on a NAS, and some consistently wrote corrupted data. > > > > > > Important commits: > > > > It looked like both the breakage and the fix came in during rc1 releases. > > > > > > > > Breakage, v6.3-rc1: > > > > I manually bisected commits in fs/smb* and fs/cifs. > > > > > > > > 3d78fe73fa12 cifs: Build the RDMA SGE list directly from an iterator > > > > > lzop and pigz worked. last working. test in progress: pbzip2 > > > > This is a first for me: lzop was fine, but pbzip2 still had issues, > > roughly a clock hour into compression. (When lzop has issues, it's > > usually within a minute or two.) > > > > > > > > 607aea3cc2a8 cifs: Remove unused code > > > > > lzop didn't work. first broken > > > > > > > > > > > > Fix, v6.10-rc1: > > > > I manually bisected commits in fs/smb. > > > > > > > > 69c3c023af25 cifs: Implement netfslib hooks > > > > > lzop didn't work. last broken one > > > > > > > > 3ee1a1fc3981 cifs: Cut over to using netfslib > > > > > lzop, pigz, pbzip2, all worked. first fixed one > > > > > I checked 607aea3cc2a8, it just removed some code in #if 0 ... #endif. > > > so this regression is not introduced in 607aea3cc2a8, but the reproduce > > > frequency is changed here. > > > > I agree. The pbzip2 results above, regarding the break bisection I > > landed on: they mark when it became more of an issue, but not when it > > started. > > > > I could re-run tests and dig into possible false negatives. It'll be > > slower going, though. > > > > > > > Another issue in 6.6.y maybe related > > > https://lore.kernel.org/linux-fsdevel/9e8f8872-f51b-4a09-a92c-49218748dd62@xxxxxxxx/T/ > > > > In comparison: I'm relieved that my issue is something that can be > > tested within hours, on one device. > > > > > > > Do this regression still happen after the following patches are applied? > > > > > > a60cc288a1a2 :Luis Chamberlain: test_xarray: add tests for advanced multi-index use > > > a08c7193e4f1 :Sidhartha Kumar: mm/filemap: remove hugetlb special casing in filemap.c > > > 6212eb4d7a63 :Hongbo Li: mm/filemap: avoid type conversion > > > > > > de60fd8ddeda :Kairui Song: mm/filemap: return early if failed to allocate memory for split > > > b2ebcf9d3d5a :Kairui Song: mm/filemap: clean up hugetlb exclusion code > > > a4864671ca0b :Kairui Song: lib/xarray: introduce a new helper xas_get_order > > > 6758c1128ceb :Kairui Song: mm/filemap: optimize filemap folio adding > > > > No luck: I cherry-picked those commits into 6.6.52, and upon testing > > lzop, the file didn't match the stream, and decompression failed. > > > > Thank you for investigating, and giving me something to try! > > > > -James
