[LTP] [PATCH] ioctl_loop06: no validate block size

[Li Wang]

On Mon, Aug 26, 2024 at 9:21 PM Li Wang <liwang@redhat.com> wrote:

>
>
> On Mon, Aug 26, 2024 at 9:15 PM Jan Stancek <jstancek@redhat.com> wrote:
>
>> On Mon, Aug 26, 2024 at 2:46 PM Li Wang <liwang@redhat.com> wrote:
>> >
>> > Hi All,
>> >
>> > On Mon, Aug 26, 2024 at 8:02 PM Li Wang <liwang@redhat.com> wrote:
>> >
>> > > Since commit 9423c653fe6110 ("loop: Don't bother validating
>> blocksize")
>> > > kernel
>> > > drop validating blocksize for both loop_configure and
>> loop_set_block_size
>> > > so
>> > > that set large block size succeeds.
>> > >
>> > > Error log:
>> > >   12 ioctl_loop06.c:76: TINFO: Using LOOP_SET_BLOCK_SIZE with arg >
>> > > PAGE_SIZE
>> > >   13 ioctl_loop06.c:59: TFAIL: Set block size succeed unexpectedly
>> > >   ...
>> > >   18 ioctl_loop06.c:76: TINFO: Using LOOP_CONFIGURE with block_size >
>> > > PAGE_SIZE
>> > >   19 ioctl_loop06.c:59:  TFAIL: Set block size succeed unexpectedly
>> > >
>> >
>> > Hmm, maybe I was wrong here, the commit says
>> >
>> >   "The block queue limits validation does this for us now."
>> >
>> > which indicates the validation is still on.
>> >
>> > So the test failure probably means a kernel bug but not a test problem.
>>
>> Before the patch, blk_validate_block_size() did validate original
>> value as unsigned long,
>> after patch it's validated after cast to unsigned short.
>>
>> In LTP thread you mentioned it failed on ppc64le/aarch64 and worked on
>> x86_64 and s390x.
>> Is it by chance now failing only on kernels with 64k page size?
>>
>
> Right, I checked the automation jobs, all recent (v6.11)
> aarch64-kernel-64k reports that fail.
>

And I verified your inference. Once I lower the invalid_value to 'pg_size +
1'
the test passed on my ppc64le platform.

And looking at the code, seems from loop_reconfigure_limits() cast to
'unsined short'
caused that. That's why another patch John submitted fe3d508ba95bc63a
("block: Validate logical block size in blk_validate_limits()") doesn't
make the
behavior consistent on all arches (with different page size).




>
>
>> (Test attempts to set block size to 2*page size.)
>>
>> >
>> > CC block devs to give some advice.
>> >
>> >
>> >
>> > >
>> > > Signed-off-by: Li Wang <liwang@redhat.com>
>> > > ---
>> > >  testcases/kernel/syscalls/ioctl/ioctl_loop06.c | 9 +++++++++
>> > >  1 file changed, 9 insertions(+)
>> > >
>> > > diff --git a/testcases/kernel/syscalls/ioctl/ioctl_loop06.c
>> > > b/testcases/kernel/syscalls/ioctl/ioctl_loop06.c
>> > > index 317f693a0..4aacd284a 100644
>> > > --- a/testcases/kernel/syscalls/ioctl/ioctl_loop06.c
>> > > +++ b/testcases/kernel/syscalls/ioctl/ioctl_loop06.c
>> > > @@ -23,6 +23,7 @@ static char dev_path[1024];
>> > >  static int dev_num, dev_fd, file_fd, attach_flag, loop_configure_sup
>> = 1;
>> > >  static unsigned int invalid_value, half_value, unalign_value;
>> > >  static struct loop_config loopconfig;
>> > > +static int novalidate_blocksize = 0;
>> > >
>> > >  static struct tcase {
>> > >         unsigned int *setvalue;
>> > > @@ -74,6 +75,11 @@ static void run(unsigned int n)
>> > >         struct tcase *tc = &tcases[n];
>> > >
>> > >         tst_res(TINFO, "%s", tc->message);
>> > > +       if ((*(tc->setvalue) == invalid_value) &&
>> novalidate_blocksize) {
>> > > +               tst_res(TCONF, "Kernel doesn't validate block size,
>> skip
>> > > invalid value test");
>> > > +               return;
>> > > +       }
>> > > +
>> > >         if (tc->ioctl_flag == LOOP_SET_BLOCK_SIZE) {
>> > >                 if (!attach_flag) {
>> > >                         tst_attach_device(dev_path, "test.img");
>> > > @@ -126,6 +132,9 @@ static void setup(void)
>> > >                 return;
>> > >         }
>> > >         loopconfig.fd = file_fd;
>> > > +
>> > > +       if ((tst_kvercmp(6, 11, 0)) >= 0)
>> > > +               novalidate_blocksize = 1;
>> > >  }
>> > >
>> > >  static void cleanup(void)
>> > > --
>> > > 2.46.0
>> > >
>> > >
>> > > --
>> > > Mailing list info: https://lists.linux.it/listinfo/ltp
>> > >
>> > >
>> >
>> > --
>> > Regards,
>> > Li Wang
>> >
>> > --
>> > Mailing list info: https://lists.linux.it/listinfo/ltp
>>
>>
>
> --
> Regards,
> Li Wang
>


-- 
Regards,
Li Wang