Re: [PATCH] generic/020: fix really long attr test failure for ceph

["Darrick J. Wong" <djwong@kernel.org>]

On Sat, Feb 18, 2023 at 02:04:36PM +0800, Zorro Lang wrote:
> On Fri, Feb 17, 2023 at 09:09:11AM -0800, Darrick J. Wong wrote:
> > On Fri, Feb 17, 2023 at 08:45:58PM +0800, xiubli@redhat.com wrote:
> > > From: Xiubo Li <xiubli@redhat.com>
> > > 
> > > If the CONFIG_CEPH_FS_SECURITY_LABEL is enabled the kernel ceph
> > > itself will set the security.selinux extended attribute to MDS.
> > > And it will also eat some space of the total size.
> > > 
> > > Fixes: https://tracker.ceph.com/issues/58742
> > > Signed-off-by: Xiubo Li <xiubli@redhat.com>
> > > ---
> > >  tests/generic/020 | 6 ++++--
> > >  1 file changed, 4 insertions(+), 2 deletions(-)
> > > 
> > > diff --git a/tests/generic/020 b/tests/generic/020
> > > index be5cecad..594535b5 100755
> > > --- a/tests/generic/020
> > > +++ b/tests/generic/020
> > > @@ -150,9 +150,11 @@ _attr_get_maxval_size()
> > >  		# it imposes a maximum size for the full set of xattrs
> > >  		# names+values, which by default is 64K.  Compute the maximum
> > >  		# taking into account the already existing attributes
> > > -		max_attrval_size=$(getfattr --dump -e hex $filename 2>/dev/null | \
> > > +		size=$(getfattr --dump -e hex $filename 2>/dev/null | \
> > >  			awk -F "=0x" '/^user/ {len += length($1) + length($2) / 2} END {print len}')
> > > -		max_attrval_size=$((65536 - $max_attrval_size - $max_attrval_namelen))
> > > +		selinux_size=$(getfattr -n 'security.selinux' --dump -e hex $filename 2>/dev/null | \
> > > +			awk -F "=0x" '/^security/ {len += length($1) + length($2) / 2} END {print len}')
> > > +		max_attrval_size=$((65536 - $size - $selinux_size - $max_attrval_namelen))
> > 
> > If this is a ceph bug, then why is the change being applied to the
> > section for FSTYP=ext* ?  Why not create a case statement for ceph?
> 
> Hi Darrick,
> 
> Looks like this change is in ceph section [1], did you hit any errors when
> you merge it?

ahahaa, diff tried to merge that hunk into _attr_get_max and not
_attr_get_maxval_size, and I didn't notice.  Question withdrawn
with apologies. :/

--D

> Thanks,
> Zorro
> 
> [1]
> _attr_get_maxval_size()
> {
>         local max_attrval_namelen="$1"
>         local filename="$2"
> 
>         # Set max attr value size in bytes based on fs type
>         case "$FSTYP" in
>         ...
>         ...
>         ceph)
>                 # CephFS does not have a maximum value for attributes.  Instead,
>                 # it imposes a maximum size for the full set of xattrs
>                 # names+values, which by default is 64K.  Compute the maximum
>                 # taking into account the already existing attributes
> ====>           max_attrval_size=$(getfattr --dump -e hex $filename 2>/dev/null | \
>                         awk -F "=0x" '/^user/ {len += length($1) + length($2) / 2} END {print len}')
> ====>           max_attrval_size=$((65536 - $max_attrval_size - $max_attrval_namelen))
> 
> 
> 
> > 
> > --D
> > 
> > >  		;;
> > >  	*)
> > >  		# Assume max ~1 block of attrs
> > > -- 
> > > 2.31.1
> > > 
> >