Re: [PATCH 2/2] tools/selftests: add guard region test for /proc/$pid/pagemap

[Lorenzo Stoakes <lorenzo.stoakes@oracle.com>]

On Fri, Feb 21, 2025 at 12:05:23PM +0000, Lorenzo Stoakes wrote:
> Add a test to the guard region self tests to assert that the
> /proc/$pid/pagemap information now made availabile to the user correctly
> identifies and reports guard regions.
>
> As a part of this change, update vm_util.h to add the new bit (note there
> is no header file in the kernel where this is exposed, the user is expected
> to provide their own mask) and utilise the helper functions there for
> pagemap functionality.
>
> Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>

Andrew - Apologies,

I managed to not commit a change I quickly made before sending this out
(I'm ill, seems it is having an impact...)

If the series is ok would you mind tacking on this fix-patch? It's simply
to rename a clumsily named define here.

No functional changes...

Thanks!

----8<----
From 60be19e88b3bfe9a6ec459115f0027721c494b30 Mon Sep 17 00:00:00 2001
From: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Date: Fri, 21 Feb 2025 13:45:48 +0000
Subject: [PATCH] fixup define name

Fix badly named define so it's consistent with the others.

Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
---
 tools/testing/selftests/mm/guard-regions.c | 6 +++---
 tools/testing/selftests/mm/vm_util.h       | 2 +-
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/mm/guard-regions.c b/tools/testing/selftests/mm/guard-regions.c
index 0c7183e8b661..280d1831bf73 100644
--- a/tools/testing/selftests/mm/guard-regions.c
+++ b/tools/testing/selftests/mm/guard-regions.c
@@ -2054,7 +2054,7 @@ TEST_F(guard_regions, pagemap)
 	for (i = 0; i < 10; i++) {
 		char *ptr_p = &ptr[i * page_size];
 		unsigned long entry = pagemap_get_entry(proc_fd, ptr_p);
-		unsigned long masked = entry & PM_GUARD_REGION_MASK;
+		unsigned long masked = entry & PM_GUARD_REGION;

 		ASSERT_EQ(masked, 0);
 	}
@@ -2070,9 +2070,9 @@ TEST_F(guard_regions, pagemap)
 	for (i = 0; i < 10; i++) {
 		char *ptr_p = &ptr[i * page_size];
 		unsigned long entry = pagemap_get_entry(proc_fd, ptr_p);
-		unsigned long masked = entry & PM_GUARD_REGION_MASK;
+		unsigned long masked = entry & PM_GUARD_REGION;

-		ASSERT_EQ(masked, i % 2 == 0 ? PM_GUARD_REGION_MASK : 0);
+		ASSERT_EQ(masked, i % 2 == 0 ? PM_GUARD_REGION : 0);
 	}

 	ASSERT_EQ(close(proc_fd), 0);
diff --git a/tools/testing/selftests/mm/vm_util.h b/tools/testing/selftests/mm/vm_util.h
index 73a11443b7f6..0e629586556b 100644
--- a/tools/testing/selftests/mm/vm_util.h
+++ b/tools/testing/selftests/mm/vm_util.h
@@ -10,7 +10,7 @@
 #define PM_SOFT_DIRTY                 BIT_ULL(55)
 #define PM_MMAP_EXCLUSIVE             BIT_ULL(56)
 #define PM_UFFD_WP                    BIT_ULL(57)
-#define PM_GUARD_REGION_MASK          BIT_ULL(58)
+#define PM_GUARD_REGION               BIT_ULL(58)
 #define PM_FILE                       BIT_ULL(61)
 #define PM_SWAP                       BIT_ULL(62)
 #define PM_PRESENT                    BIT_ULL(63)
--
2.48.1