On Sat, Jun 17, 2017 at 12:11:05AM +0800, Zorro Lang wrote:
> Recently we found a bug by trigger a page fault when io-vector of
> writev is in processing. If do memset between malloc() and write
> operations, memset will init the pages. So do memset randomly
> maybe help to cover above situation.
>
> Signed-off-by: Zorro Lang <zlang@xxxxxxxxxx>
> ---
> ltp/fsstress.c | 12 ++++++++----
> 1 file changed, 8 insertions(+), 4 deletions(-)
>
> diff --git a/ltp/fsstress.c b/ltp/fsstress.c
> index 4ff90d5..e1b73e4 100644
> --- a/ltp/fsstress.c
> +++ b/ltp/fsstress.c
> @@ -1924,7 +1924,8 @@ do_aio_rw(int opno, long r, int flags)
> off = (off64_t)(lr % MIN(stb.st_size + (1024 * 1024), MAXFSIZE));
> off -= (off % align);
> off %= maxfsize;
> - memset(buf, nameseq & 0xff, len);
> + /* randomly memset maybe trigger page fault at write time */
> + if (random() / 2) memset(buf, nameseq & 0xff, len);
Sorry for my mistake, all "(random() / 2)" should be "random() % 2".
Thanks,
Zorro
> io_prep_pwrite(&iocb, fd, buf, len, off);
> } else {
> off = (off64_t)(lr % stb.st_size);
> @@ -2455,7 +2456,8 @@ dwrite_f(int opno, long r)
> buf = memalign(diob.d_mem, len);
> off %= maxfsize;
> lseek64(fd, off, SEEK_SET);
> - memset(buf, nameseq & 0xff, len);
> + /* randomly memset maybe trigger page fault at write time */
> + if (random() / 2) memset(buf, nameseq & 0xff, len);
> e = write(fd, buf, len) < 0 ? errno : 0;
> free(buf);
> if (v)
> @@ -3672,7 +3674,8 @@ write_f(int opno, long r)
> lseek64(fd, off, SEEK_SET);
> len = (random() % FILELEN_MAX) + 1;
> buf = malloc(len);
> - memset(buf, nameseq & 0xff, len);
> + /* randomly memset maybe trigger page fault at write time */
> + if (random() / 2) memset(buf, nameseq & 0xff, len);
> e = write(fd, buf, len) < 0 ? errno : 0;
> free(buf);
> if (v)
> @@ -3733,7 +3736,8 @@ writev_f(int opno, long r)
> lseek64(fd, off, SEEK_SET);
> len = (random() % FILELEN_MAX) + 1;
> buf = malloc(len);
> - memset(buf, nameseq & 0xff, len);
> + /* randomly memset maybe trigger page fault at write time */
> + if (random() / 2) memset(buf, nameseq & 0xff, len);
>
> iovcnt = (random() % MIN(len, IOV_MAX)) + 1;
> iov = malloc(sizeof(struct iovec) * iovcnt);
> --
> 2.7.4
>
> --
> To unsubscribe from this list: send the line "unsubscribe fstests" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
--
To unsubscribe from this list: send the line "unsubscribe fstests" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
