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selftests/mm: Drop redundant open() in mprotect_tests()

PATCH Applied Hongfu Li 6 participants 6 messages Aug 17 – Aug 18

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Hongfu Li

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#0 lore raw

PATCH 1/1 selftests/mm: Drop redundant open() in mprotect_tests()

From: Hongfu Li <[email protected]>

Remove duplicate open() for local pagemap_fd in mprotect_tests() that shadows the global pagemap_fd already opened in main(). The local fd is never used in the function.

Signed-off-by Hongfu Li <[email protected]>
---
 tools/testing/selftests/mm/pagemap_ioctl.c | 6 ------
 1 file changed, 6 deletions(-)
tools/testing/selftests/mm/pagemap_ioctl.c +0 -6
index cfd1987339c1..eadc7159ca5b 100644
@@ -1332,12 +1332,6 @@ int mprotect_tests(void)
 	int ret;
 	char *mem, *mem2;
 	struct page_region vec;
-	int pagemap_fd = open("/proc/self/pagemap", O_RDONLY);
-
-	if (pagemap_fd < 0) {
-		fprintf(stderr, "open() failed\n");
-		exit(1);
-	}
 
 	/* 1. Map two pages */
 	mem = mmap(0, 2 * page_size, PROT_READ|PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
Signature · 1 line
2.54.0
reviewer Reviewed-by on v1 1/1
#1 lore raw

+cc Muhammad

Quoted 7 lines · Hongfu Li

From: Hongfu Li <[email protected]>

Remove duplicate open() for local pagemap_fd in mprotect_tests() that shadows the global pagemap_fd already opened in main(). The local fd is never used in the function.

Signed-off-by Hongfu Li <[email protected]>

Hmm yeah it's not even closed either...

I'm assuming this was an error in the origianl tests, Muhammad - I'm guessing some artifact of a previous approach or similar?

Anyway, LGTM, so:

Reviewed-by Lorenzo Stoakes (ARM) <[email protected]>
Quoted 22 lines
---
 tools/testing/selftests/mm/pagemap_ioctl.c | 6 ------
 1 file changed, 6 deletions(-)
tools/testing/selftests/mm/pagemap_ioctl.c +0 -7
index cfd1987339c1..eadc7159ca5b 100644
@@ -1332,12 +1332,6 @@ int mprotect_tests(void)
 	int ret;
 	char *mem, *mem2;
 	struct page_region vec;
-	int pagemap_fd = open("/proc/self/pagemap", O_RDONLY);
-
-	if (pagemap_fd < 0) {
-		fprintf(stderr, "open() failed\n");
-		exit(1);
-	}
 
 	/* 1. Map two pages */
 	mem = mmap(0, 2 * page_size, PROT_READ|PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
--
Quoted 2 lines

2.54.0

--
Cheers, Lorenzo

Reviewed-by
#2 lore raw
Quoted 9 lines · Lorenzo Stoakes (ARM)

+cc Muhammad

Quoted 6 lines · Hongfu Li

From: Hongfu Li <[email protected]>

Remove duplicate open() for local pagemap_fd in mprotect_tests() that shadows the global pagemap_fd already opened in main(). The local fd is never used in the function.

Quoted 6 lines
Quoted 1 line
Signed-off-by Hongfu Li <[email protected]>

Hmm yeah it's not even closed either...

I'm assuming this was an error in the origianl tests, Muhammad - I'm guessing some artifact of a previous approach or similar?

Its definitively the dead code.

Reviewed-by Muhammad Usama Anjum <[email protected]>
Quoted 33 lines

Anyway, LGTM, so:

Reviewed-by Lorenzo Stoakes (ARM) <[email protected]>
Quoted 22 lines
---
 tools/testing/selftests/mm/pagemap_ioctl.c | 6 ------
 1 file changed, 6 deletions(-)
tools/testing/selftests/mm/pagemap_ioctl.c +0 -7
index cfd1987339c1..eadc7159ca5b 100644
@@ -1332,12 +1332,6 @@ int mprotect_tests(void)
 	int ret;
 	char *mem, *mem2;
 	struct page_region vec;
-	int pagemap_fd = open("/proc/self/pagemap", O_RDONLY);
-
-	if (pagemap_fd < 0) {
-		fprintf(stderr, "open() failed\n");
-		exit(1);
-	}
 
 	/* 1. Map two pages */
 	mem = mmap(0, 2 * page_size, PROT_READ|PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
--
Quoted 2 lines

2.54.0

--
Cheers, Lorenzo

Reviewed-by on v1 1/1
#3 lore raw
In reply to Hongfu Li
Quoted 5 lines · On Mon, 17 Aug 2026 16:06:16 +0800 Hongfu Li <[email protected]> wrote:

From: Hongfu Li <[email protected]>

Remove duplicate open() for local pagemap_fd in mprotect_tests() that shadows the global pagemap_fd already opened in main(). The local fd is never used in the function.

Nice catch!

Quoted 2 lines
Signed-off-by Hongfu Li <[email protected]>
Reviewed-by SJ Park <[email protected]>

Thanks,
SJ

[...]

Reviewed-by on v1 1/1
#4 lore raw
In reply to Hongfu Li
Quoted 7 lines · Hongfu Li

From: Hongfu Li <[email protected]>

Remove duplicate open() for local pagemap_fd in mprotect_tests() that shadows the global pagemap_fd already opened in main(). The local fd is never used in the function.

Signed-off-by Hongfu Li <[email protected]>
Reviewed-by Anshuman Khandual <[email protected]>
Quoted 24 lines
---
 tools/testing/selftests/mm/pagemap_ioctl.c | 6 ------
 1 file changed, 6 deletions(-)
tools/testing/selftests/mm/pagemap_ioctl.c +0 -6
index cfd1987339c1..eadc7159ca5b 100644
@@ -1332,12 +1332,6 @@ int mprotect_tests(void)
 	int ret;
 	char *mem, *mem2;
 	struct page_region vec;
-	int pagemap_fd = open("/proc/self/pagemap", O_RDONLY);
-
-	if (pagemap_fd < 0) {
-		fprintf(stderr, "open() failed\n");
-		exit(1);
-	}
 
 	/* 1. Map two pages */
 	mem = mmap(0, 2 * page_size, PROT_READ|PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
Signature · 1 line
2.54.0