The advantage of kcalloc is, that will prevent integer overflows which could result from the multiplication of number of elements and size and it is also a bit nicer to read.
The semantic patch that makes this change is available in https://lkml.org/lkml/2011/11/25/107 Signed-off-by: Thomas Meyer <[email protected]> --- diff -u -p a/drivers/block/cciss_scsi.c b/drivers/block/cciss_scsi.c --- a/drivers/block/cciss_scsi.c 2011-11-28 19:36:47.343430551 +0100 +++ b/drivers/block/cciss_scsi.c 2011-11-28 19:49:24.922716381 +0100 @@ -534,10 +534,10 @@ adjust_cciss_scsi_table(ctlr_info_t *h, int nadded, nremoved; struct Scsi_Host *sh = NULL; - added = kzalloc(sizeof(*added) * CCISS_MAX_SCSI_DEVS_PER_HBA, - GFP_KERNEL); - removed = kzalloc(sizeof(*removed) * CCISS_MAX_SCSI_DEVS_PER_HBA, + added = kcalloc(CCISS_MAX_SCSI_DEVS_PER_HBA, sizeof(*added), GFP_KERNEL); + removed = kcalloc(CCISS_MAX_SCSI_DEVS_PER_HBA, sizeof(*removed), + GFP_KERNEL); if (!added || !removed) { dev_warn(&h->pdev->dev, @@ -1191,8 +1191,8 @@ cciss_update_non_disk_devices(ctlr_info_ ld_buff = kzalloc(reportlunsize, GFP_KERNEL); inq_buff = kmalloc(OBDR_TAPE_INQ_SIZE, GFP_KERNEL); - currentsd = kzalloc(sizeof(*currentsd) * - (CCISS_MAX_SCSI_DEVS_PER_HBA+1), GFP_KERNEL); + currentsd = kcalloc(CCISS_MAX_SCSI_DEVS_PER_HBA + 1, + sizeof(*currentsd), GFP_KERNEL); if (ld_buff == NULL || inq_buff == NULL || currentsd == NULL) { printk(KERN_ERR "cciss: out of memory\n"); goto out; diff -u -p a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c --- a/drivers/block/xen-blkfront.c 2011-11-13 11:07:22.680095573 +0100 +++ b/drivers/block/xen-blkfront.c 2011-11-28 19:49:29.109460410 +0100 @@ -156,7 +156,7 @@ static int xlbd_reserve_minors(unsigned if (end > nr_minors) { unsigned long *bitmap, *old; - bitmap = kzalloc(BITS_TO_LONGS(end) * sizeof(*bitmap), + bitmap = kcalloc(BITS_TO_LONGS(end), sizeof(*bitmap), GFP_KERNEL); if (bitmap == NULL) return -ENOMEM; _______________________________________________ Virtualization mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/virtualization
