| Message ID | 20220112092846.1467088-1-ruansy.fnst@fujitsu.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | generic/670: allow _mread_range() races with reflink_range() | expand |
On Wed, Jan 12, 2022 at 05:28:46PM +0800, Shiyang Ruan wrote: > mread copies data one-byte-at-a-time, so it may races with > reflink_range() who invalidates page cache of the dest file. > Allow this race by adjusting the egrep regexp. > > Reported-by: Darrick J. Wong <djwong@kernel.org> > Suggested-by: Darrick J. Wong <djwong@kernel.org> > Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com> Looks reasonable; I'll put this in the test system for tonight and report back if I see anything strange. I didn't see anything obvious after a dozen or so rounds. Reviewed-by: Darrick J. Wong <djwong@kernel.org> --D > --- > tests/generic/670 | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/tests/generic/670 b/tests/generic/670 > index 83fbd0b9..4a895d90 100755 > --- a/tests/generic/670 > +++ b/tests/generic/670 > @@ -40,7 +40,10 @@ _cp_reflink $testdir/file1 $testdir/file3 > _scratch_cycle_mount > > fbytes() { > - egrep -v '(61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61|62 62 62 62 62 62 62 62 62 62 62 62 62 62 62 62)' > + # Different with generic/164,165, mread copies data from mmapped area > + # one-byte-at-a-time, which may cause races during reflink_range(). > + # So the result of _mread_range() may be a mix of 61 and 62. > + egrep -v '((61|62) ){15}(61|62)' > } > > reader() { > -- > 2.34.1 > > >
diff --git a/tests/generic/670 b/tests/generic/670 index 83fbd0b9..4a895d90 100755 --- a/tests/generic/670 +++ b/tests/generic/670 @@ -40,7 +40,10 @@ _cp_reflink $testdir/file1 $testdir/file3 _scratch_cycle_mount fbytes() { - egrep -v '(61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61|62 62 62 62 62 62 62 62 62 62 62 62 62 62 62 62)' + # Different with generic/164,165, mread copies data from mmapped area + # one-byte-at-a-time, which may cause races during reflink_range(). + # So the result of _mread_range() may be a mix of 61 and 62. + egrep -v '((61|62) ){15}(61|62)' } reader() {
mread copies data one-byte-at-a-time, so it may races with reflink_range() who invalidates page cache of the dest file. Allow this race by adjusting the egrep regexp. Reported-by: Darrick J. Wong <djwong@kernel.org> Suggested-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com> --- tests/generic/670 | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)