[LTP] [PATCH] mkswap: make the test device size is aligned to pagesize

Li Wang
2016-08-15T09:25:08Z

On Tue, Aug 09, 2016 at 06:41:18PM +0200, Cyril Hrubis wrote:
> Hi!
> > We get failures like below because of 'DEVICE_SIZE-10000' makes the
> > loop device size is not aligned to system PAGE_SIZE any more.
>
> What version of mkswap.c you have?

My version is:

# rpm -qf /sbin/mkswap
util-linux-2.23.2-33.el7.ppc64

if (block_count) {
/* this silly user specified the number of blocks explicitly */
uint64_t blks = strtou64_or_err(block_count,
_("invalid block count argument"));
PAGES = blks / (pagesize / 1024);
}
sz = get_size(device_name);

>
> Looking into util-linux-2.26.2 all it does with user specified number of
> blocks is:
>
> ctl.npages = blks / (ctl.pagesize / 1024);
>
> There is no check that blks is divideable by pagesize/1024.

I build util-linux-2.28 from upstrem source and also get the errors.

# mkswap -V
mkswap from util-linux 2.28.237-47bd89

# ./runltp -f commands
mkswap01 1 TINFO : Using test device LTP_DEV='/dev/loop0'
mkswap01 1 TFAIL : 'mkswap /dev/loop0 ' failed, not expected.
mkswap01 2 TFAIL : 'mkswap /dev/loop0 90000' failed, not expected.
mkswap01 3 TINFO : Can not do swapon on /dev/loop0.
mkswap01 3 TINFO : Device size specified by 'mkswap' greater than real size.
mkswap01 3 TINFO : Swapon failed expectedly.
mkswap01 3 TPASS : 'mkswap -f /dev/loop0 110000' passed.

-----------------

Additionally, we'd better change the bs=1kB to bs=1024 in runltp file,
since it will get page aligned block device for all arches.

The original LTP_DEV size is 102400000 bytes:

# grep 'bs=' runltp -n
981: dd if=/dev/zero of=${TMP}/test.img bs=1kB count=102400

From dd manual:
N and BYTES may be followed by the following multiplicative suffixes:
c =1, w =2, b =512, kB =1000, K =1024, MB =1000*1000, M =1024*1024,
xM =M GB =1000*1000*1000, G =1024*1024*1024, and so on for T, P, E, Z, Y.

Regards,
Li Wang