diff mbox series

[v15,13/17] IB, arm64: untag user pointers in ib_uverbs_(re)reg_mr()

Message ID 66d044ab9445dcf36a96205a109458ac23f38b73.1557160186.git.andreyknvl@google.com (mailing list archive)
State New, archived
Headers show
Series arm64: untag user pointers passed to the kernel | expand

Commit Message

Andrey Konovalov May 6, 2019, 4:30 p.m. UTC
This patch is a part of a series that extends arm64 kernel ABI to allow to
pass tagged user pointers (with the top byte set to something else other
than 0x00) as syscall arguments.

ib_uverbs_(re)reg_mr() use provided user pointers for vma lookups (through
e.g. mlx4_get_umem_mr()), which can only by done with untagged pointers.

Untag user pointers in these functions.

Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
---
 drivers/infiniband/core/uverbs_cmd.c | 4 ++++
 1 file changed, 4 insertions(+)

Comments

Jason Gunthorpe May 6, 2019, 7:50 p.m. UTC | #1
On Mon, May 06, 2019 at 06:30:59PM +0200, Andrey Konovalov wrote:
> This patch is a part of a series that extends arm64 kernel ABI to allow to
> pass tagged user pointers (with the top byte set to something else other
> than 0x00) as syscall arguments.
> 
> ib_uverbs_(re)reg_mr() use provided user pointers for vma lookups (through
> e.g. mlx4_get_umem_mr()), which can only by done with untagged pointers.
> 
> Untag user pointers in these functions.
> 
> Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
> ---
>  drivers/infiniband/core/uverbs_cmd.c | 4 ++++
>  1 file changed, 4 insertions(+)

I think this is OK.. We should really get it tested though.. Leon?

Jason
Leon Romanovsky May 7, 2019, 6:33 a.m. UTC | #2
On Mon, May 06, 2019 at 04:50:20PM -0300, Jason Gunthorpe wrote:
> On Mon, May 06, 2019 at 06:30:59PM +0200, Andrey Konovalov wrote:
> > This patch is a part of a series that extends arm64 kernel ABI to allow to
> > pass tagged user pointers (with the top byte set to something else other
> > than 0x00) as syscall arguments.
> >
> > ib_uverbs_(re)reg_mr() use provided user pointers for vma lookups (through
> > e.g. mlx4_get_umem_mr()), which can only by done with untagged pointers.
> >
> > Untag user pointers in these functions.
> >
> > Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
> > ---
> >  drivers/infiniband/core/uverbs_cmd.c | 4 ++++
> >  1 file changed, 4 insertions(+)
>
> I think this is OK.. We should really get it tested though.. Leon?

It can be done after v5.2-rc1.

Thanks

>
> Jason
diff mbox series

Patch

diff --git a/drivers/infiniband/core/uverbs_cmd.c b/drivers/infiniband/core/uverbs_cmd.c
index 062a86c04123..36e7b52577d0 100644
--- a/drivers/infiniband/core/uverbs_cmd.c
+++ b/drivers/infiniband/core/uverbs_cmd.c
@@ -708,6 +708,8 @@  static int ib_uverbs_reg_mr(struct uverbs_attr_bundle *attrs)
 	if (ret)
 		return ret;
 
+	cmd.start = untagged_addr(cmd.start);
+
 	if ((cmd.start & ~PAGE_MASK) != (cmd.hca_va & ~PAGE_MASK))
 		return -EINVAL;
 
@@ -790,6 +792,8 @@  static int ib_uverbs_rereg_mr(struct uverbs_attr_bundle *attrs)
 	if (ret)
 		return ret;
 
+	cmd.start = untagged_addr(cmd.start);
+
 	if (cmd.flags & ~IB_MR_REREG_SUPPORTED || !cmd.flags)
 		return -EINVAL;