patch 'eal: fix side effect in some pointer arithmetic macros' has been queued to stable release 20.11.7

[luca.boccassi at gmail.com]

Hi,

FYI, your patch has been queued to stable release 20.11.7

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 11/05/22. 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.

Queued patches are on a temporary branch at:
https://github.com/kevintraynor/dpdk-stable

This queued commit can be viewed at:
https://github.com/kevintraynor/dpdk-stable/commit/1aa7dc7481d5bbacc6c86dfb87a81ff6c0eeda12

Thanks.

Luca Boccassi

---
>From 1aa7dc7481d5bbacc6c86dfb87a81ff6c0eeda12 Mon Sep 17 00:00:00 2001
From: Dmitry Kozlyuk <dmitry.kozliuk at gmail.com>
Date: Sat, 27 Aug 2022 14:32:19 +0300
Subject: [PATCH] eal: fix side effect in some pointer arithmetic macros
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

[ upstream commit 1a7374c95678183aef6f40b64074752831a33d26 ]

RTE_PTR_SUB(ptr, x) and RTE_PTR_ALIGN_FLOOR() worked incorrectly
if "ptr" was an expression:

    uint32_t arr[3];

    RTE_PTR_SUB(arr + 1, sizeof(arr[0]));
    // expected: (uint32_t *)((uintptr_t)(arr + 1) - 4) == arr
    // actual:   (uint32_t *)((uintptr_t) arr + 1  - 4) != arr

    RTE_PTR_ALIGN_FLOOR(arr + 2, sizeof(arr[0]));
    // expected: RTE_ALIGN_FLOOR((uintptr_t)(arr + 2), 4) == &arr[2]
    // actual:   RTE_ALIGN_FLOOR((uintptr_t) arr + 2,  4) == &arr[0]

Fix the macros and extend the relevant unit test.
Convert uses of a custom test failure macro to RTE_TEST_ASSERT*().

Fixes: af75078fece3 ("first public release")

Signed-off-by: Dmitry Kozlyuk <dmitry.kozliuk at gmail.com>
Reviewed-by: Morten Brørup <mb at smartsharesystems.com>
Acked-by: Bruce Richardson <bruce.richardson at intel.com>
Acked-by: Chengwen Feng <fengchengwen at huawei.com>
---
 app/test/test_common.c              | 52 ++++++++++++++++++++---------
 lib/librte_eal/include/rte_common.h |  4 +--
 2 files changed, 39 insertions(+), 17 deletions(-)

diff --git a/app/test/test_common.c b/app/test/test_common.c
index 12bd1cad90..181c8be3be 100644
--- a/app/test/test_common.c
+++ b/app/test/test_common.c
@@ -25,27 +25,49 @@ test_macros(int __rte_unused unused_parm)
 #define SMALLER 0x1000U
 #define BIGGER 0x2000U
 #define PTR_DIFF BIGGER - SMALLER
-#define FAIL_MACRO(x)\
-	{printf(#x "() test failed!\n");\
-	return -1;}
 
 	uintptr_t unused = 0;
+	uint32_t arr[3];
 
 	RTE_SET_USED(unused);
 
-	if ((uintptr_t)RTE_PTR_ADD(SMALLER, PTR_DIFF) != BIGGER)
-		FAIL_MACRO(RTE_PTR_ADD);
-	if ((uintptr_t)RTE_PTR_SUB(BIGGER, PTR_DIFF) != SMALLER)
-		FAIL_MACRO(RTE_PTR_SUB);
-	if (RTE_PTR_DIFF(BIGGER, SMALLER) != PTR_DIFF)
-		FAIL_MACRO(RTE_PTR_DIFF);
-	if (RTE_MAX(SMALLER, BIGGER) != BIGGER)
-		FAIL_MACRO(RTE_MAX);
-	if (RTE_MIN(SMALLER, BIGGER) != SMALLER)
-		FAIL_MACRO(RTE_MIN);
+	RTE_TEST_ASSERT_EQUAL((uintptr_t)RTE_PTR_ADD(SMALLER, PTR_DIFF), BIGGER,
+		"RTE_PTR_ADD");
+	RTE_TEST_ASSERT_EQUAL((uintptr_t)RTE_PTR_SUB(BIGGER, PTR_DIFF), SMALLER,
+		"RTE_PTR_SUB");
+	RTE_TEST_ASSERT_EQUAL(RTE_PTR_DIFF(BIGGER, SMALLER), PTR_DIFF,
+		"RTE_PTR_DIFF");
+	RTE_TEST_ASSERT_EQUAL(RTE_MAX(SMALLER, BIGGER), BIGGER,
+		"RTE_MAX");
+	RTE_TEST_ASSERT_EQUAL(RTE_MIN(SMALLER, BIGGER), SMALLER,
+		"RTE_MIN");
 
-	if (strncmp(RTE_STR(test), "test", sizeof("test")))
-		FAIL_MACRO(RTE_STR);
+	RTE_TEST_ASSERT_EQUAL(RTE_PTR_ADD(arr + 1, sizeof(arr[0])), &arr[2],
+		"RTE_PTR_ADD(expr, x)");
+	RTE_TEST_ASSERT_EQUAL(RTE_PTR_SUB(arr + 1, sizeof(arr[0])), &arr[0],
+		"RTE_PTR_SUB(expr, x)");
+	RTE_TEST_ASSERT_EQUAL(RTE_PTR_ALIGN_FLOOR(arr + 2, 4), &arr[2],
+		"RTE_PTR_ALIGN_FLOOR(expr, x)");
+	RTE_TEST_ASSERT_EQUAL(RTE_PTR_ALIGN_CEIL(arr + 2, 4), &arr[2],
+		"RTE_PTR_ALIGN_CEIL(expr, x)");
+	RTE_TEST_ASSERT_EQUAL(RTE_PTR_ALIGN(arr + 2, 4), &arr[2],
+		"RTE_PTR_ALIGN(expr, x)");
+
+	RTE_TEST_ASSERT_EQUAL(
+		RTE_PTR_ALIGN_FLOOR(RTE_PTR_ADD(&arr[1], 1), 4), &arr[1],
+		"RTE_PTR_ALIGN_FLOOR(x < y/2, y)");
+	RTE_TEST_ASSERT_EQUAL(
+		RTE_PTR_ALIGN_FLOOR(RTE_PTR_ADD(&arr[1], 3), 4), &arr[1],
+		"RTE_PTR_ALIGN_FLOOR(x > y/2, y)");
+	RTE_TEST_ASSERT_EQUAL(
+		RTE_PTR_ALIGN_CEIL(RTE_PTR_ADD(&arr[1], 3), 4), &arr[2],
+		"RTE_PTR_ALIGN_CEIL(x < y/2, y)");
+	RTE_TEST_ASSERT_EQUAL(
+		RTE_PTR_ALIGN_CEIL(RTE_PTR_ADD(&arr[1], 1), 4), &arr[2],
+		"RTE_PTR_ALIGN_CEIL(x > y/2, y)");
+
+	RTE_TEST_ASSERT(strncmp(RTE_STR(test), "test", sizeof("test")) == 0,
+		"RTE_STR");
 
 	return 0;
 }
diff --git a/lib/librte_eal/include/rte_common.h b/lib/librte_eal/include/rte_common.h
index 677b52a2f8..853adcb249 100644
--- a/lib/librte_eal/include/rte_common.h
+++ b/lib/librte_eal/include/rte_common.h
@@ -255,7 +255,7 @@ static void __attribute__((destructor(RTE_PRIO(prio)), used)) func(void)
 /**
  * subtract a byte-value offset from a pointer
  */
-#define RTE_PTR_SUB(ptr, x) ((void*)((uintptr_t)ptr - (x)))
+#define RTE_PTR_SUB(ptr, x) ((void *)((uintptr_t)(ptr) - (x)))
 
 /**
  * get the difference between two pointer values, i.e. how far apart
@@ -280,7 +280,7 @@ static void __attribute__((destructor(RTE_PRIO(prio)), used)) func(void)
  * must be a power-of-two value.
  */
 #define RTE_PTR_ALIGN_FLOOR(ptr, align) \
-	((typeof(ptr))RTE_ALIGN_FLOOR((uintptr_t)ptr, align))
+	((typeof(ptr))RTE_ALIGN_FLOOR((uintptr_t)(ptr), align))
 
 /**
  * Macro to align a value to a given power-of-two. The resultant value
-- 
2.34.1

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2022-11-03 09:27:25.658313581 +0000
+++ 0002-eal-fix-side-effect-in-some-pointer-arithmetic-macro.patch	2022-11-03 09:27:25.293420892 +0000
@@ -1 +1 @@
-From 1a7374c95678183aef6f40b64074752831a33d26 Mon Sep 17 00:00:00 2001
+From 1aa7dc7481d5bbacc6c86dfb87a81ff6c0eeda12 Mon Sep 17 00:00:00 2001
@@ -8,0 +9,2 @@
+[ upstream commit 1a7374c95678183aef6f40b64074752831a33d26 ]
+
@@ -26 +27,0 @@
-Cc: stable at dpdk.org
@@ -33,3 +34,3 @@
- app/test/test_common.c       | 56 +++++++++++++++++++++++++-----------
- lib/eal/include/rte_common.h |  4 +--
- 2 files changed, 41 insertions(+), 19 deletions(-)
+ app/test/test_common.c              | 52 ++++++++++++++++++++---------
+ lib/librte_eal/include/rte_common.h |  4 +--
+ 2 files changed, 39 insertions(+), 17 deletions(-)
@@ -38 +39 @@
-index ef177cecb1..f89e1eb7ee 100644
+index 12bd1cad90..181c8be3be 100644
@@ -41 +42 @@
-@@ -25,31 +25,53 @@ test_macros(int __rte_unused unused_parm)
+@@ -25,27 +25,49 @@ test_macros(int __rte_unused unused_parm)
@@ -50 +50,0 @@
- 	unsigned int smaller = SMALLER, bigger  = BIGGER;
@@ -55,3 +54,0 @@
- 	RTE_SWAP(smaller, bigger);
--	if (smaller != BIGGER && bigger != SMALLER)
--		FAIL_MACRO(RTE_SWAP);
@@ -68,2 +64,0 @@
-+	RTE_TEST_ASSERT(smaller == BIGGER && bigger == SMALLER,
-+		"RTE_SWAP");
@@ -112,5 +107,5 @@
-diff --git a/lib/eal/include/rte_common.h b/lib/eal/include/rte_common.h
-index a96cc2a138..d517e9f75f 100644
---- a/lib/eal/include/rte_common.h
-+++ b/lib/eal/include/rte_common.h
-@@ -295,7 +295,7 @@ static void __attribute__((destructor(RTE_PRIO(prio)), used)) func(void)
+diff --git a/lib/librte_eal/include/rte_common.h b/lib/librte_eal/include/rte_common.h
+index 677b52a2f8..853adcb249 100644
+--- a/lib/librte_eal/include/rte_common.h
++++ b/lib/librte_eal/include/rte_common.h
+@@ -255,7 +255,7 @@ static void __attribute__((destructor(RTE_PRIO(prio)), used)) func(void)
@@ -125 +120 @@
-@@ -320,7 +320,7 @@ static void __attribute__((destructor(RTE_PRIO(prio)), used)) func(void)
+@@ -280,7 +280,7 @@ static void __attribute__((destructor(RTE_PRIO(prio)), used)) func(void)