Re: [PATCH 4.4 085/134] test_firmware: fix setting old custom fw path back on exit

From: Luis R. Rodriguez
Date: Tue Apr 03 2018 - 15:06:54 EST


On Sun, Apr 01, 2018 at 07:56:55PM +0100, Ben Hutchings wrote:
> On Mon, 2018-03-19 at 19:06 +0100, Greg Kroah-Hartman wrote:
> > 4.4-stable review patch.  If anyone has any objections, please let me know.
> >
> > ------------------
> >
> > From: "Luis R. Rodriguez" <mcgrof@xxxxxxxxxx>
> >
> >
> > [ Upstream commit 65c79230576873b312c3599479c1e42355c9f349 ]
> >
> > The file /sys/module/firmware_class/parameters/path can be used
> > to set a custom firmware path. The fw_filesystem.sh script creates
> > a temporary directory to add a test firmware file to be used during
> > testing, in order for this to work it uses the custom path syfs file
> > and it was supposed to reset back the file on execution exit. The
> > script failed to do this due to a typo, it was using OLD_PATH instead
> > of OLD_FWPATH, since its inception since v3.17.
> >
> > Its not as easy to just keep the old setting, it turns out that
> > resetting an empty setting won't actually do what we want, we need
> > to check if it was empty and set an empty space.
>
> That doesn't seem to work either. I don't see any stripping of spaces
> in the generic parameter code or firmware_class, and the parameter
> reads back as a space:
>
> # echo -n ' ' > path
> # od -tx1 path
> 0000000 20 0a
> 0000002
>
> However, this seems to work:
>
> # printf '\0' > path
> # od -tx1 path
> 0000000 0a
> 0000001

Not sure what you mean, care to send a patch?

Luis
>
> Ben.
>
> > Without this we end up having the temporary path always set after
> > we run these tests.
> >
> > Fixes: 0a8adf58475 ("test: add firmware_class loader test")
> > Signed-off-by: Luis R. Rodriguez <mcgrof@xxxxxxxxxx>
> > Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> > Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
> > Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> > ---
> >  tools/testing/selftests/firmware/fw_filesystem.sh |    5 ++++-
> >  1 file changed, 4 insertions(+), 1 deletion(-)
> >
> > --- a/tools/testing/selftests/firmware/fw_filesystem.sh
> > +++ b/tools/testing/selftests/firmware/fw_filesystem.sh
> > @@ -28,7 +28,10 @@ test_finish()
> >   if [ "$HAS_FW_LOADER_USER_HELPER" = "yes" ]; then
> >   echo "$OLD_TIMEOUT" >/sys/class/firmware/timeout
> >   fi
> > - echo -n "$OLD_PATH" >/sys/module/firmware_class/parameters/path
> > + if [ "$OLD_FWPATH" = "" ]; then
> > + OLD_FWPATH=" "
> > + fi
> > + echo -n "$OLD_FWPATH" >/sys/module/firmware_class/parameters/path
> >   rm -f "$FW"
> >   rmdir "$FWPATH"
> >  }
> >
> >
> >
> --
> Ben Hutchings
> Software Developer, Codethink Ltd.
>
>

--
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