On Fri, Oct 07, 2022 at 01:18:55PM +0800, Zorro Lang wrote:
> On Wed, Oct 05, 2022 at 03:31:15PM -0700, Darrick J. Wong wrote:
> > From: Darrick J. Wong <djwong@xxxxxxxxxx>
> >
> > If someone sets kernel.core_uses_pid (or kernel.core_pattern), any
> > coredumps generated by fstests might have names that are longer than
> > just "core". Since the pid isn't all that useful by itself, let's
> > record the coredumps by hash when we save them, so that we don't waste
> > space storing identical crash dumps.
> >
> > Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx>
> > ---
> > check | 26 ++++++++++++++++++++++----
> > common/rc | 16 ++++++++++++++++
> > 2 files changed, 38 insertions(+), 4 deletions(-)
> >
> >
> > diff --git a/check b/check
> > index af23572ccc..654d986b27 100755
> > --- a/check
> > +++ b/check
> > @@ -913,11 +913,19 @@ function run_section()
> > sts=$?
> > fi
> >
> > - if [ -f core ]; then
> > - _dump_err_cont "[dumped core]"
> > - mv core $RESULT_BASE/$seqnum.core
> > + # If someone sets kernel.core_pattern or kernel.core_uses_pid,
> > + # coredumps generated by fstests might have a longer name than
> > + # just "core". Use globbing to find the most common patterns,
> > + # assuming there are no other coredump capture packages set up.
> > + local cores=0
> > + for i in core core.*; do
>
> I'm wondering if it should be "for i in core*" ? The coredump file only can be
> "core" with dot ".", can it with "-" or "_" or others?
The ".$pid" pattern is encoded in the kernel function format_corename:
/* Backward compatibility with core_uses_pid:
*
* If core_pattern does not include a %p (as is the default)
* and core_uses_pid is set, then .%pid will be appended to
* the filename. Do not do this for piped commands. */
if (!ispipe && !pid_in_pattern && core_uses_pid) {
err = cn_printf(cn, ".%d", task_tgid_vnr(current));
if (err)
return err;
}
Note that even this is an incomplete solution because the sysadmin could
configure a totally different corename pattern, pipe it to another
program, or whatever, and fstests fails to capture any dumps at all.
Longer term it'd be theoretically nice to turn core_pattern into a
cgroup-manageable tunable and teach ./check to capture all the
coredumps, but I am not volunteering to write that much new
infrastructure. :/
--D
>
> > + test -f "$i" || continue
> > + if ((cores++ == 0)); then
> > + _dump_err_cont "[dumped core]"
> > + fi
> > + _save_coredump "$i"
> > tc_status="fail"
> > - fi
> > + done
> >
> > if [ -f $seqres.notrun ]; then
> > $timestamp && _timestamp
> > @@ -950,6 +958,16 @@ function run_section()
> > # of the check script itself.
> > (_adjust_oom_score 250; _check_filesystems) || tc_status="fail"
> > _check_dmesg || tc_status="fail"
> > +
> > + # Save any coredumps from the post-test fs checks
> > + for i in core core.*; do
> > + test -f "$i" || continue
> > + if ((cores++ == 0)); then
> > + _dump_err_cont "[dumped core]"
> > + fi
> > + _save_coredump "$i"
> > + tc_status="fail"
> > + done
> > fi
> >
> > # Reload the module after each test to check for leaks or
> > diff --git a/common/rc b/common/rc
> > index d1f3d56bf8..9750d06a9a 100644
> > --- a/common/rc
> > +++ b/common/rc
> > @@ -4948,6 +4948,22 @@ _create_file_sized()
> > return $ret
> > }
> >
> > +_save_coredump()
> > +{
> > + local path="$1"
> > +
> > + local core_hash="$(_md5_checksum "$path")"
> > + local out_file="$RESULT_BASE/$seqnum.core.$core_hash"
> > +
> > + if [ -s "$out_file" ]; then
> > + rm -f "$path"
> > + return
> > + fi
> > + rm -f "$out_file"
> > +
> > + mv "$path" "$out_file"
> > +}
> > +
> > init_rc
> >
> > ################################################################################
> >
>
