On 11/28, Eric Biggers wrote:
> On Mon, Nov 28, 2022 at 10:48:41PM -0800, Jaegeuk Kim wrote:
> > > static void f2fs_finish_read_bio(struct bio *bio, bool in_task)
> > > {
> > > struct bio_vec *bv;
> > > struct bvec_iter_all iter_all;
> > > + struct bio_post_read_ctx *ctx = bio->bi_private;
> > >
> > > - /*
> > > - * Update and unlock the bio's pagecache pages, and put the
> > > - * decompression context for any compressed pages.
> > > - */
> > > bio_for_each_segment_all(bv, bio, iter_all) {
> > > struct page *page = bv->bv_page;
> > >
> > > if (f2fs_is_compressed_page(page)) {
> > > - if (bio->bi_status)
> > > + if (!ctx->decompression_attempted)
> >
> > If seems this causes a panic due to the ctx nullified by f2fs_verify_bio.
> >
>
> Thanks for catching that! I've sent out v5 that checks for 'ctx &&
> !ctx->decompression_attempted' here. That's the right thing to do, since if ctx
> is NULL then decompression must have been attempted.
>
> I'd like to get rid of freeing the bio_post_read_ctx in f2fs_verify_bio().
> But I believe it's still needed, at least in theory.
>
> Do you have a suggestion for testing f2fs compression + verity with xfstests?
> I missed this because compression isn't covered by the "verity" group tests.
> Maybe there should be an "f2fs/compress" config in xfstests-bld that uses mkfs
> and mount options that cause all files to be automatically compressed, similar
> to how f2fs/encrypt automatically encrypts all files with test_dummy_encryption.
I used for fsstress+fault_injection+shutdown loop with compressed and
non-compressed directories with:
# mkfs.f2fs -f -O extra_attr -O project_quota -O compression -g android /dev/$DEV
# mount -t f2fs -o discard,fsync_mode=nobarrier,reserve_root=32768,checkpoint_merge,atgc,compress_cache /dev/$DEV $TESTDIR
# mkdir $TESTDIR/comp
# f2fs_io setflags compression $TESTDIR/comp
# fsstress [options] -d $TESTDIR/comp
I think you can simply mount with "-o compress_extension=*" to compress
everything.
>
> - Eric
