[dpdk-stable] patch 'net/mlx5: fix doorbell bitmap management offsets' has been queued to stable release 19.11.3

[luca.boccassi at gmail.com]

Hi,

FYI, your patch has been queued to stable release 19.11.3

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 05/24/20. So please
shout if anyone has objections.

Also note that after the patch there's a diff of the upstream commit vs the
patch applied to the branch. This will indicate if there was any rebasing
needed to apply to the stable branch. If there were code changes for rebasing
(ie: not only metadata diffs), please double check that the rebase was
correctly done.

Thanks.

Luca Boccassi

---
>From 8fecf8ad1da951c1283202840763f884a49ceddb Mon Sep 17 00:00:00 2001
From: Bing Zhao <bingz at mellanox.com>
Date: Fri, 15 May 2020 16:13:58 +0800
Subject: [PATCH] net/mlx5: fix doorbell bitmap management offsets

[ upstream commit 25a59a3076461b269b0f489a9f6865042092d1ee ]

The doorbell record is organized with page and bitmap. When some new
doorbell needs to be associated with a queue, the bit will be set
in the bitmap to indicate the corresponding doorbell occupied. A
counter is used to record the number of doorbell occupied to speed
up the searching.
If the number reaches the maximal value of a pre-defined number of a
page, a new page will be allocated. If not, then the bitmap will be
checked to find a free one.
The LSHIFT and OR (AND NOT) operations are used to update the bitmap
of a page. But 1 will be treated as a signed integer when compiling.
When the shift number is 31, the shifted value will be considered as
negative. Then a wrong extension will be done when setting it to a
64-bits variable. All the upper 32-bits will be set to 1 by such
extension.
Then a wrong offset value will be calculated because of this. The
next 64 bits will be also treated as the bitmap and get corrupted
through the bit set operation.
The immediate value 1 needs to be used as 64 bits width explicitly.

Fixes: 21cae8580fd0 ("net/mlx5: allocate door-bells via DevX")

Signed-off-by: Bing Zhao <bingz at mellanox.com>
Acked-by: Viacheslav Ovsiienko <viacheslavo at mellanox.com>
Acked-by: Matan Azrad <matan at mellanox.com>
---
 drivers/net/mlx5/mlx5.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/mlx5/mlx5.c b/drivers/net/mlx5/mlx5.c
index 9ecf31da7c..2349a62674 100644
--- a/drivers/net/mlx5/mlx5.c
+++ b/drivers/net/mlx5/mlx5.c
@@ -1948,7 +1948,7 @@ mlx5_get_dbr(struct rte_eth_dev *dev, struct mlx5_devx_dbr_page **dbr_page)
 	/* Find the first clear bit. */
 	assert(i < MLX5_DBR_BITMAP_SIZE);
 	j = rte_bsf64(~page->dbr_bitmap[i]);
-	page->dbr_bitmap[i] |= (1 << j);
+	page->dbr_bitmap[i] |= (UINT64_C(1) << j);
 	page->dbr_count++;
 	*dbr_page = page;
 	return (((i * 64) + j) * sizeof(uint64_t));
@@ -1993,7 +1993,7 @@ mlx5_release_dbr(struct rte_eth_dev *dev, uint32_t umem_id, uint64_t offset)
 		int i = offset / 64;
 		int j = offset % 64;
 
-		page->dbr_bitmap[i] &= ~(1 << j);
+		page->dbr_bitmap[i] &= ~(UINT64_C(1) << j);
 	}
 	return ret;
 }
-- 
2.20.1

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2020-05-22 10:37:40.226057429 +0100
+++ 0026-net-mlx5-fix-doorbell-bitmap-management-offsets.patch	2020-05-22 10:37:39.144413000 +0100
@@ -1,8 +1,10 @@
-From 25a59a3076461b269b0f489a9f6865042092d1ee Mon Sep 17 00:00:00 2001
+From 8fecf8ad1da951c1283202840763f884a49ceddb Mon Sep 17 00:00:00 2001
 From: Bing Zhao <bingz at mellanox.com>
 Date: Fri, 15 May 2020 16:13:58 +0800
 Subject: [PATCH] net/mlx5: fix doorbell bitmap management offsets
 
+[ upstream commit 25a59a3076461b269b0f489a9f6865042092d1ee ]
+
 The doorbell record is organized with page and bitmap. When some new
 doorbell needs to be associated with a queue, the bit will be set
 in the bitmap to indicate the corresponding doorbell occupied. A
@@ -23,7 +25,6 @@
 The immediate value 1 needs to be used as 64 bits width explicitly.
 
 Fixes: 21cae8580fd0 ("net/mlx5: allocate door-bells via DevX")
-Cc: stable at dpdk.org
 
 Signed-off-by: Bing Zhao <bingz at mellanox.com>
 Acked-by: Viacheslav Ovsiienko <viacheslavo at mellanox.com>
@@ -33,19 +34,19 @@
  1 file changed, 2 insertions(+), 2 deletions(-)
 
 diff --git a/drivers/net/mlx5/mlx5.c b/drivers/net/mlx5/mlx5.c
-index 14458098ec..ab4adecdc3 100644
+index 9ecf31da7c..2349a62674 100644
 --- a/drivers/net/mlx5/mlx5.c
 +++ b/drivers/net/mlx5/mlx5.c
-@@ -2174,7 +2174,7 @@ mlx5_get_dbr(struct rte_eth_dev *dev, struct mlx5_devx_dbr_page **dbr_page)
+@@ -1948,7 +1948,7 @@ mlx5_get_dbr(struct rte_eth_dev *dev, struct mlx5_devx_dbr_page **dbr_page)
  	/* Find the first clear bit. */
- 	MLX5_ASSERT(i < MLX5_DBR_BITMAP_SIZE);
+ 	assert(i < MLX5_DBR_BITMAP_SIZE);
  	j = rte_bsf64(~page->dbr_bitmap[i]);
 -	page->dbr_bitmap[i] |= (1 << j);
 +	page->dbr_bitmap[i] |= (UINT64_C(1) << j);
  	page->dbr_count++;
  	*dbr_page = page;
  	return (((i * 64) + j) * sizeof(uint64_t));
-@@ -2219,7 +2219,7 @@ mlx5_release_dbr(struct rte_eth_dev *dev, uint32_t umem_id, uint64_t offset)
+@@ -1993,7 +1993,7 @@ mlx5_release_dbr(struct rte_eth_dev *dev, uint32_t umem_id, uint64_t offset)
  		int i = offset / 64;
  		int j = offset % 64;