FAILED: patch "[PATCH] IB/core: Make testing MR flags for writability a static" failed to apply to 4.4-stable tree

FAILED: patch "[PATCH] IB/core: Make testing MR flags for writability a static" failed to apply to 4.4-stable tree

[gregkh]

The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

>From 08bb558ac11ab944e0539e78619d7b4c356278bd Mon Sep 17 00:00:00 2001
From: Jack Morgenstein <jackm@dev.mellanox.co.il>
Date: Wed, 23 May 2018 15:30:30 +0300
Subject: [PATCH] IB/core: Make testing MR flags for writability a static
 inline function

Make the MR writability flags check, which is performed in umem.c,
a static inline function in file ib_verbs.h

This allows the function to be used by low-level infiniband drivers.

Cc: <stable@vger.kernel.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

diff --git a/drivers/infiniband/core/umem.c b/drivers/infiniband/core/umem.c
index 2b6c9b516070..d76455edd292 100644
--- a/drivers/infiniband/core/umem.c
+++ b/drivers/infiniband/core/umem.c
@@ -119,16 +119,7 @@ struct ib_umem *ib_umem_get(struct ib_ucontext *context, unsigned long addr,
 	umem->length     = size;
 	umem->address    = addr;
 	umem->page_shift = PAGE_SHIFT;
-	/*
-	 * We ask for writable memory if any of the following
-	 * access flags are set.  "Local write" and "remote write"
-	 * obviously require write access.  "Remote atomic" can do
-	 * things like fetch and add, which will modify memory, and
-	 * "MW bind" can change permissions by binding a window.
-	 */
-	umem->writable  = !!(access &
-		(IB_ACCESS_LOCAL_WRITE   | IB_ACCESS_REMOTE_WRITE |
-		 IB_ACCESS_REMOTE_ATOMIC | IB_ACCESS_MW_BIND));
+	umem->writable   = ib_access_writable(access);
 
 	if (access & IB_ACCESS_ON_DEMAND) {
 		ret = ib_umem_odp_get(context, umem, access);
diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index 9fc8a825aa28..20fa5c591e81 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -3734,6 +3734,20 @@ static inline int ib_check_mr_access(int flags)
 	return 0;
 }
 
+static inline bool ib_access_writable(int access_flags)
+{
+	/*
+	 * We have writable memory backing the MR if any of the following
+	 * access flags are set.  "Local write" and "remote write" obviously
+	 * require write access.  "Remote atomic" can do things like fetch and
+	 * add, which will modify memory, and "MW bind" can change permissions
+	 * by binding a window.
+	 */
+	return access_flags &
+		(IB_ACCESS_LOCAL_WRITE   | IB_ACCESS_REMOTE_WRITE |
+		 IB_ACCESS_REMOTE_ATOMIC | IB_ACCESS_MW_BIND);
+}
+
 /**
  * ib_check_mr_status: lightweight check of MR status.
  *     This routine may provide status checks on a selected

Re: FAILED: patch "[PATCH] IB/core: Make testing MR flags for writability a static" failed to apply to 4.4-stable tree

[Sudip Mukherjee]

[-- Attachment #1: Type: text/plain, Size: 545 bytes --]

Hi Greg,

On Sun, Jul 01, 2018 at 11:37:25AM +0200, gregkh@linuxfoundation.org wrote:
> 
> The patch below does not apply to the 4.4-stable tree.
> If someone wants it applied there, or to any other stable or longterm
> tree, then please email the backport, including the original git commit
> id to <stable@vger.kernel.org>.

The attached backported patch should apply to 4.4-stable and also to
4.9-stable.

Though I am confused about why this should be in stable, unless some
later fix, required in stable, depends on this.


--
Regards
Sudip

[-- Attachment #2: 0002-IB-core-Make-testing-MR-flags-for-writability-a-stat.patch --]
[-- Type: text/x-diff, Size: 2762 bytes --]

>From 5a8146ce6d32fd2321a0935ea7169be2d785fd41 Mon Sep 17 00:00:00 2001
From: Jack Morgenstein <jackm@dev.mellanox.co.il>
Date: Wed, 23 May 2018 15:30:30 +0300
Subject: [PATCH] IB/core: Make testing MR flags for writability a static inline function

commit 08bb558ac11ab944e0539e78619d7b4c356278bd upstream

Make the MR writability flags check, which is performed in umem.c,
a static inline function in file ib_verbs.h

This allows the function to be used by low-level infiniband drivers.

Cc: <stable@vger.kernel.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
---
 drivers/infiniband/core/umem.c | 11 +----------
 include/rdma/ib_verbs.h        | 14 ++++++++++++++
 2 files changed, 15 insertions(+), 10 deletions(-)

diff --git a/drivers/infiniband/core/umem.c b/drivers/infiniband/core/umem.c
index 6790ebb366dd..98fd9a594841 100644
--- a/drivers/infiniband/core/umem.c
+++ b/drivers/infiniband/core/umem.c
@@ -122,16 +122,7 @@ struct ib_umem *ib_umem_get(struct ib_ucontext *context, unsigned long addr,
 	umem->address   = addr;
 	umem->page_size = PAGE_SIZE;
 	umem->pid       = get_task_pid(current, PIDTYPE_PID);
-	/*
-	 * We ask for writable memory if any of the following
-	 * access flags are set.  "Local write" and "remote write"
-	 * obviously require write access.  "Remote atomic" can do
-	 * things like fetch and add, which will modify memory, and
-	 * "MW bind" can change permissions by binding a window.
-	 */
-	umem->writable  = !!(access &
-		(IB_ACCESS_LOCAL_WRITE   | IB_ACCESS_REMOTE_WRITE |
-		 IB_ACCESS_REMOTE_ATOMIC | IB_ACCESS_MW_BIND));
+	umem->writable   = ib_access_writable(access);
 
 	if (access & IB_ACCESS_ON_DEMAND) {
 		put_pid(umem->pid);
diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index 120da1d7f57e..10fefb0dc640 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -3007,6 +3007,20 @@ static inline int ib_check_mr_access(int flags)
 	return 0;
 }
 
+static inline bool ib_access_writable(int access_flags)
+{
+	/*
+	 * We have writable memory backing the MR if any of the following
+	 * access flags are set.  "Local write" and "remote write" obviously
+	 * require write access.  "Remote atomic" can do things like fetch and
+	 * add, which will modify memory, and "MW bind" can change permissions
+	 * by binding a window.
+	 */
+	return access_flags &
+		(IB_ACCESS_LOCAL_WRITE   | IB_ACCESS_REMOTE_WRITE |
+		 IB_ACCESS_REMOTE_ATOMIC | IB_ACCESS_MW_BIND);
+}
+
 /**
  * ib_check_mr_status: lightweight check of MR status.
  *     This routine may provide status checks on a selected
-- 
2.11.0

Re: FAILED: patch "[PATCH] IB/core: Make testing MR flags for writability a static" failed to apply to 4.4-stable tree

[Greg KH]

On Sun, Aug 12, 2018 at 02:56:49PM +0100, Sudip Mukherjee wrote:
> Hi Greg,
> 
> On Sun, Jul 01, 2018 at 11:37:25AM +0200, gregkh@linuxfoundation.org wrote:
> > 
> > The patch below does not apply to the 4.4-stable tree.
> > If someone wants it applied there, or to any other stable or longterm
> > tree, then please email the backport, including the original git commit
> > id to <stable@vger.kernel.org>.
> 
> The attached backported patch should apply to 4.4-stable and also to
> 4.9-stable.
> 
> Though I am confused about why this should be in stable, unless some
> later fix, required in stable, depends on this.

That's a good question.  Can some IB developer please answer this before
I queue this up?

thanks,

greg k-h

Re: FAILED: patch "[PATCH] IB/core: Make testing MR flags for writability a static" failed to apply to 4.4-stable tree

[Jason Gunthorpe]

On Sun, Aug 12, 2018 at 05:28:10PM +0200, Greg KH wrote:
> On Sun, Aug 12, 2018 at 02:56:49PM +0100, Sudip Mukherjee wrote:
> > Hi Greg,
> > 
> > On Sun, Jul 01, 2018 at 11:37:25AM +0200, gregkh@linuxfoundation.org wrote:
> > > 
> > > The patch below does not apply to the 4.4-stable tree.
> > > If someone wants it applied there, or to any other stable or longterm
> > > tree, then please email the backport, including the original git commit
> > > id to <stable@vger.kernel.org>.
> > 
> > The attached backported patch should apply to 4.4-stable and also to
> > 4.9-stable.
> > 
> > Though I am confused about why this should be in stable, unless some
> > later fix, required in stable, depends on this.
> 
> That's a good question.  Can some IB developer please answer this before
> I queue this up?

It is required for this upstream patch:

commit d8f9cc328c8888369880e2527e9186d745f2bbf6
Author: Jack Morgenstein <jackm@dev.mellanox.co.il>
Date:   Wed May 23 15:30:31 2018 +0300

    IB/mlx4: Mark user MR as writable if actual virtual memory is writable
    
    To allow rereg_user_mr to modify the MR from read-only to writable without
    using get_user_pages again, we needed to define the initial MR as writable.
    However, this was originally done unconditionally, without taking into
    account the writability of the underlying virtual memory.
    
    As a result, any attempt to register a read-only MR over read-only
    virtual memory failed.
    
    To fix this, do not add the writable flag bit when the user virtual memory
    is not writable (e.g. const memory).
    
    However, when the underlying memory is NOT writable (and we therefore
    do not define the initial MR as writable), the IB core adds a
    "force writable" flag to its user-pages request. If this succeeds,
    the reg_user_mr caller gets a writable copy of the original pages.
    
    If the user-space caller then does a rereg_user_mr operation to enable
    writability, this will succeed. This should not be allowed, since
    the original virtual memory was not writable.
    
    Cc: <stable@vger.kernel.org>
    Fixes: 9376932d0c26 ("IB/mlx4_ib: Add support for user MR re-registration")
    Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
    Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
    Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

Re: FAILED: patch "[PATCH] IB/core: Make testing MR flags for writability a static" failed to apply to 4.4-stable tree

[Sudip Mukherjee]

On Sun, Aug 12, 2018 at 11:06:07AM -0600, Jason Gunthorpe wrote:
> On Sun, Aug 12, 2018 at 05:28:10PM +0200, Greg KH wrote:
> > On Sun, Aug 12, 2018 at 02:56:49PM +0100, Sudip Mukherjee wrote:
> > > Hi Greg,
> > > 
> > > On Sun, Jul 01, 2018 at 11:37:25AM +0200, gregkh@linuxfoundation.org wrote:
> > > > 
> > > > The patch below does not apply to the 4.4-stable tree.
> > > > If someone wants it applied there, or to any other stable or longterm
> > > > tree, then please email the backport, including the original git commit
> > > > id to <stable@vger.kernel.org>.
> > > 
> > > The attached backported patch should apply to 4.4-stable and also to
> > > 4.9-stable.
> > > 
> > > Though I am confused about why this should be in stable, unless some
> > > later fix, required in stable, depends on this.
> > 
> > That's a good question.  Can some IB developer please answer this before
> > I queue this up?
> 
> It is required for this upstream patch:
> 
> commit d8f9cc328c8888369880e2527e9186d745f2bbf6
> Author: Jack Morgenstein <jackm@dev.mellanox.co.il>
> Date:   Wed May 23 15:30:31 2018 +0300

Thanks Jason.
Looks like d8f9cc328c88 ("IB/mlx4: Mark user MR as writable if actual
virtual memory is writable") will be needed in both 4.4-stable and
4.9-stable, but will need backporting.

--
Regards
Sudip