2023-10-31 14:44:55

by Stefano Garzarella

Subject: [PATCH] vdpa_sim_blk: allocate the buffer zeroed

Deleting and recreating a device can lead to having the same
content as the old device, so let's always allocate buffers
completely zeroed out.

Fixes: abebb16254b3 ("vdpa_sim_blk: support shared backend")
Suggested-by: Qing Wang <[email protected]>
Signed-off-by: Stefano Garzarella <[email protected]>
---
drivers/vdpa/vdpa_sim/vdpa_sim_blk.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
index b3a3cb165795..b137f3679343 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
@@ -437,7 +437,7 @@ static int vdpasim_blk_dev_add(struct vdpa_mgmt_dev *mdev, const char *name,
if (blk->shared_backend) {
blk->buffer = shared_buffer;
} else {
- blk->buffer = kvmalloc(VDPASIM_BLK_CAPACITY << SECTOR_SHIFT,
+ blk->buffer = kvzalloc(VDPASIM_BLK_CAPACITY << SECTOR_SHIFT,
GFP_KERNEL);
if (!blk->buffer) {
ret = -ENOMEM;
@@ -495,7 +495,7 @@ static int __init vdpasim_blk_init(void)
goto parent_err;

if (shared_backend) {
- shared_buffer = kvmalloc(VDPASIM_BLK_CAPACITY << SECTOR_SHIFT,
+ shared_buffer = kvzalloc(VDPASIM_BLK_CAPACITY << SECTOR_SHIFT,
GFP_KERNEL);
if (!shared_buffer) {
ret = -ENOMEM;
--
2.41.0

2023-10-31 17:53:08

by Eugenio Perez Martin

Subject: Re: [PATCH] vdpa_sim_blk: allocate the buffer zeroed

On Tue, Oct 31, 2023 at 3:44 PM Stefano Garzarella <[email protected]> wrote:
>
> Deleting and recreating a device can lead to having the same
> content as the old device, so let's always allocate buffers
> completely zeroed out.
>
> Fixes: abebb16254b3 ("vdpa_sim_blk: support shared backend")
> Suggested-by: Qing Wang <[email protected]>

Acked-by: Eugenio Pérez <[email protected]>

> Signed-off-by: Stefano Garzarella <[email protected]>
> ---
> drivers/vdpa/vdpa_sim/vdpa_sim_blk.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
> index b3a3cb165795..b137f3679343 100644
> --- a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
> +++ b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
> @@ -437,7 +437,7 @@ static int vdpasim_blk_dev_add(struct vdpa_mgmt_dev *mdev, const char *name,
> if (blk->shared_backend) {
> blk->buffer = shared_buffer;
> } else {
> - blk->buffer = kvmalloc(VDPASIM_BLK_CAPACITY << SECTOR_SHIFT,
> + blk->buffer = kvzalloc(VDPASIM_BLK_CAPACITY << SECTOR_SHIFT,
> GFP_KERNEL);
> if (!blk->buffer) {
> ret = -ENOMEM;
> @@ -495,7 +495,7 @@ static int __init vdpasim_blk_init(void)
> goto parent_err;
>
> if (shared_backend) {
> - shared_buffer = kvmalloc(VDPASIM_BLK_CAPACITY << SECTOR_SHIFT,
> + shared_buffer = kvzalloc(VDPASIM_BLK_CAPACITY << SECTOR_SHIFT,
> GFP_KERNEL);
> if (!shared_buffer) {
> ret = -ENOMEM;
> --
> 2.41.0
>

2023-11-01 00:37:09

by Jason Wang

Subject: Re: [PATCH] vdpa_sim_blk: allocate the buffer zeroed

On Wed, Nov 1, 2023 at 1:52 AM Eugenio Perez Martin <[email protected]> wrote:
>
> On Tue, Oct 31, 2023 at 3:44 PM Stefano Garzarella <[email protected]> wrote:
> >
> > Deleting and recreating a device can lead to having the same
> > content as the old device, so let's always allocate buffers
> > completely zeroed out.
> >
> > Fixes: abebb16254b3 ("vdpa_sim_blk: support shared backend")
> > Suggested-by: Qing Wang <[email protected]>
>
> Acked-by: Eugenio Pérez <[email protected]>

Acked-by: Jason Wang <[email protected]>

Thanks

>
> > Signed-off-by: Stefano Garzarella <[email protected]>
> > ---
> > drivers/vdpa/vdpa_sim/vdpa_sim_blk.c | 4 ++--
> > 1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
> > index b3a3cb165795..b137f3679343 100644
> > --- a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
> > +++ b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
> > @@ -437,7 +437,7 @@ static int vdpasim_blk_dev_add(struct vdpa_mgmt_dev *mdev, const char *name,
> > if (blk->shared_backend) {
> > blk->buffer = shared_buffer;
> > } else {
> > - blk->buffer = kvmalloc(VDPASIM_BLK_CAPACITY << SECTOR_SHIFT,
> > + blk->buffer = kvzalloc(VDPASIM_BLK_CAPACITY << SECTOR_SHIFT,
> > GFP_KERNEL);
> > if (!blk->buffer) {
> > ret = -ENOMEM;
> > @@ -495,7 +495,7 @@ static int __init vdpasim_blk_init(void)
> > goto parent_err;
> >
> > if (shared_backend) {
> > - shared_buffer = kvmalloc(VDPASIM_BLK_CAPACITY << SECTOR_SHIFT,
> > + shared_buffer = kvzalloc(VDPASIM_BLK_CAPACITY << SECTOR_SHIFT,
> > GFP_KERNEL);
> > if (!shared_buffer) {
> > ret = -ENOMEM;
> > --
> > 2.41.0
> >
>