| Message ID | 1322563758-26317-1-git-send-email-roman.tereshonkov@nokia.com |
|---|---|
| State | Accepted |
| Commit | 556f063580db2953a7e53cd46b47724246320f60 |
| Headers | show |
On Tue, 2011-11-29 at 12:49 +0200, Roman Tereshonkov wrote: > The array of unsigned long pointed by oops_page_used is allocated > by vmalloc which requires the size to be in bytes. > > Signed-off-by: Roman Tereshonkov <roman.tereshonkov@nokia.com> > --- > drivers/mtd/mtdoops.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/drivers/mtd/mtdoops.c b/drivers/mtd/mtdoops.c > index 1e2fa62..0782b31 100644 > --- a/drivers/mtd/mtdoops.c > +++ b/drivers/mtd/mtdoops.c > @@ -369,7 +369,7 @@ static void mtdoops_notify_add(struct mtd_info *mtd) > > /* oops_page_used is a bit field */ > cxt->oops_page_used = vmalloc(DIV_ROUND_UP(mtdoops_pages, > - BITS_PER_LONG)); > + BITS_PER_LONG) * sizeof(unsigned long)); But it is already in bytes. I do not understand which problem this patch fixes - it looks incorrect to me.
On Sun, Dec 04, 2011 at 03:44:57PM +0200, Artem Bityutskiy wrote: > On Tue, 2011-11-29 at 12:49 +0200, Roman Tereshonkov wrote: > > The array of unsigned long pointed by oops_page_used is allocated > > by vmalloc which requires the size to be in bytes. > > > > Signed-off-by: Roman Tereshonkov <roman.tereshonkov at nokia.com> > > --- > > drivers/mtd/mtdoops.c | 2 +- > > 1 files changed, 1 insertions(+), 1 deletions(-) > > > > diff --git a/drivers/mtd/mtdoops.c b/drivers/mtd/mtdoops.c > > index 1e2fa62..0782b31 100644 > > --- a/drivers/mtd/mtdoops.c > > +++ b/drivers/mtd/mtdoops.c > > @@ -369,7 +369,7 @@ static void mtdoops_notify_add(struct mtd_info *mtd) > > > > /* oops_page_used is a bit field */ > > cxt->oops_page_used = vmalloc(DIV_ROUND_UP(mtdoops_pages, > > - BITS_PER_LONG)); > > + BITS_PER_LONG) * sizeof(unsigned long)); > > But it is already in bytes. I do not understand which problem this patch > fixes - it looks incorrect to me. BITS_PER_LONG is equal to 32. If we want to allocate memory for 32 pages with one bit per page then 32 / BITS_PER_LONG is equal to 1 byte that is 8 bits. To fix it we need to multiply the result by sizeof(unsigned long) equal to 4. Regards Roman Tereshonkov > > -- > Best Regards, > Artem Bityutskiy > -------------- next part -------------- > A non-text attachment was scrubbed... > Name: signature.asc > Type: application/pgp-signature > Size: 836 bytes > Desc: This is a digitally signed message part > URL: <http://lists.infradead.org/pipermail/linux-mtd/attachments/20111204/a96b926e/attachment.sig>
On Wed, 2011-12-07 at 17:25 +0200, Roman Tereshonkov wrote: > BITS_PER_LONG is equal to 32. > If we want to allocate memory for 32 pages with one bit per page then > 32 / BITS_PER_LONG is equal to 1 byte that is 8 bits. > To fix it we need to multiply the result by sizeof(unsigned long) > equal to 4. Ah, you are right. This should also go to the stable tree, I've added Cc: stable@kernel.org Pushed to l2-mtd-2.6.git thanks. Artem.
diff --git a/drivers/mtd/mtdoops.c b/drivers/mtd/mtdoops.c index 1e2fa62..0782b31 100644 --- a/drivers/mtd/mtdoops.c +++ b/drivers/mtd/mtdoops.c @@ -369,7 +369,7 @@ static void mtdoops_notify_add(struct mtd_info *mtd) /* oops_page_used is a bit field */ cxt->oops_page_used = vmalloc(DIV_ROUND_UP(mtdoops_pages, - BITS_PER_LONG)); + BITS_PER_LONG) * sizeof(unsigned long)); if (!cxt->oops_page_used) { printk(KERN_ERR "mtdoops: could not allocate page array\n"); return;
The array of unsigned long pointed by oops_page_used is allocated by vmalloc which requires the size to be in bytes. Signed-off-by: Roman Tereshonkov <roman.tereshonkov@nokia.com> --- drivers/mtd/mtdoops.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-)