Unverified Commit 62d648c4 authored by Lorenzo Stoakes's avatar Lorenzo Stoakes Committed by Christian Brauner
Browse files

selftests/mm: use PIDFD_SELF in guard pages test 



Now we have PIDFD_SELF available for process_madvise(), make use of it in
the guard pages test.

This is both more convenient and asserts that PIDFD_SELF works as expected.

Signed-off-by: default avatarLorenzo Stoakes <lorenzo.stoakes@oracle.com>
Link: https://lore.kernel.org/r/69fbbe088d3424de9983e145228459cb05a8f13d.1738268370.git.lorenzo.stoakes@oracle.com


Reviewed-by: default avatarShakeel Butt <shakeel.butt@linux.dev>
Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent 2bbf47f2

tools/testing/selftests/mm/guard-pages.c

+4 −12
Original line number Diff line number Diff line
@@ -19,6 +19,8 @@ 
#include <sys/uio.h>

#include <unistd.h>



#include "../pidfd/pidfd.h"



/*

 * Ignore the checkpatch warning, as per the C99 standard, section 7.14.1.1:

 *
@@ -50,11 +52,6 @@ static void handle_fatal(int c) 
	siglongjmp(signal_jmp_buf, c);

}



static int pidfd_open(pid_t pid, unsigned int flags)

{

	return syscall(SYS_pidfd_open, pid, flags);

}



static ssize_t sys_process_madvise(int pidfd, const struct iovec *iovec,

				   size_t n, int advice, unsigned int flags)

{
@@ -370,14 +367,10 @@ TEST_F(guard_pages, multi_vma) 
TEST_F(guard_pages, process_madvise)

{

	const unsigned long page_size = self->page_size;

	pid_t pid = getpid();

	int pidfd = pidfd_open(pid, 0);

	char *ptr_region, *ptr1, *ptr2, *ptr3;

	ssize_t count;

	struct iovec vec[6];



	ASSERT_NE(pidfd, -1);



	/* Reserve region to map over. */

	ptr_region = mmap(NULL, 100 * page_size, PROT_NONE,

			  MAP_ANON | MAP_PRIVATE, -1, 0);
@@ -425,7 +418,7 @@ TEST_F(guard_pages, process_madvise) 
	ASSERT_EQ(munmap(&ptr_region[99 * page_size], page_size), 0);



	/* Now guard in one step. */

	count = sys_process_madvise(pidfd, vec, 6, MADV_GUARD_INSTALL, 0);

	count = sys_process_madvise(PIDFD_SELF, vec, 6, MADV_GUARD_INSTALL, 0);



	/* OK we don't have permission to do this, skip. */

	if (count == -1 && errno == EPERM)
@@ -446,7 +439,7 @@ TEST_F(guard_pages, process_madvise) 
	ASSERT_FALSE(try_read_write_buf(&ptr3[19 * page_size]));



	/* Now do the same with unguard... */

	count = sys_process_madvise(pidfd, vec, 6, MADV_GUARD_REMOVE, 0);

	count = sys_process_madvise(PIDFD_SELF, vec, 6, MADV_GUARD_REMOVE, 0);



	/* ...and everything should now succeed. */
@@ -463,7 +456,6 @@ TEST_F(guard_pages, process_madvise) 
	ASSERT_EQ(munmap(ptr1, 10 * page_size), 0);

	ASSERT_EQ(munmap(ptr2, 5 * page_size), 0);

	ASSERT_EQ(munmap(ptr3, 20 * page_size), 0);

	close(pidfd);

}



/* Assert that unmapping ranges does not leave guard markers behind. */