lkml.org 
[lkml]   [2020]   [Feb]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH] selftests/vm: Fix map_hugetlb length used for testing read and write
From
Date
On Sat, 2020-02-15 at 03:49 -0300, Leonardo Bras wrote:
> Hello Christophe, thank you for the patch.
>
> On Thu, 2020-02-06 at 08:42 +0000, Christophe Leroy wrote:
> > Commit fa7b9a805c79 ("tools/selftest/vm: allow choosing mem size and
> > page size in map_hugetlb") added the possibility to change the size
> > of memory mapped for the test, but left the read and write test using
> > the default value. This is unnoticed when mapping a length greater
> > than the default one, but segfaults otherwise.
> >
> > Fix read_bytes() and write_bytes() by giving them the real length.
> >
> > Also fix the call to munmap().
> >
> > Fixes: fa7b9a805c79 ("tools/selftest/vm: allow choosing mem size and page size in map_hugetlb")
> > Cc: stable@vger.kernel.org
> > Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
> > ---
> > tools/testing/selftests/vm/map_hugetlb.c | 14 +++++++-------
> > 1 file changed, 7 insertions(+), 7 deletions(-)
> >
> > diff --git a/tools/testing/selftests/vm/map_hugetlb.c b/tools/testing/selftests/vm/map_hugetlb.c
> > index 5a2d7b8efc40..6af951900aa3 100644
> > --- a/tools/testing/selftests/vm/map_hugetlb.c
> > +++ b/tools/testing/selftests/vm/map_hugetlb.c
> > @@ -45,20 +45,20 @@ static void check_bytes(char *addr)
> > printf("First hex is %x\n", *((unsigned int *)addr));
> > }
> >
> > -static void write_bytes(char *addr)
> > +static void write_bytes(char *addr, size_t length)
> > {
> > unsigned long i;
> >
> > - for (i = 0; i < LENGTH; i++)
> > + for (i = 0; i < length; i++)
> > *(addr + i) = (char)i;
> > }
> >
> > -static int read_bytes(char *addr)
> > +static int read_bytes(char *addr, size_t length)
> > {
> > unsigned long i;
> >
> > check_bytes(addr);
> > - for (i = 0; i < LENGTH; i++)
> > + for (i = 0; i < length; i++)
> > if (*(addr + i) != (char)i) {
> > printf("Mismatch at %lu\n", i);
> > return 1;
> > @@ -96,11 +96,11 @@ int main(int argc, char **argv)
> >
> > printf("Returned address is %p\n", addr);
> > check_bytes(addr);
> > - write_bytes(addr);
> > - ret = read_bytes(addr);
> > + write_bytes(addr, length);
> > + ret = read_bytes(addr, length);
> >
> > /* munmap() length of MAP_HUGETLB memory must be hugepage aligned */
> > - if (munmap(addr, LENGTH)) {
> > + if (munmap(addr, length)) {
> > perror("munmap");
> > exit(1);
> > }
>
> I agree with you, it's a needed fix.
>
> FWIW:
> Reviwed-by: Leonardo Bras <leonardo@linux.ibm.com>
Sorry, typo.
Reviewed-by: Leonardo Bras <leonardo@linux.ibm.com>
[unhandled content-type:application/pgp-signature]
\
 
 \ /
  Last update: 2020-02-17 15:11    [W:0.178 / U:5.272 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site