6.6-stable review patch. If anyone has any objections, please let me know.
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From: Michael Ellerman mpe@ellerman.id.au
[ Upstream commit f13242a46438e690067a4bf47068fde4d5719947 ]
Currently the mount_setattr_test fails on machines with a 64K PAGE_SIZE, with errors such as:
# RUN mount_setattr_idmapped.invalid_fd_negative ... mkfs.ext4: No space left on device while writing out and closing file system # mount_setattr_test.c:1055:invalid_fd_negative:Expected system("mkfs.ext4 -q /mnt/C/ext4.img") (256) == 0 (0) # invalid_fd_negative: Test terminated by assertion # FAIL mount_setattr_idmapped.invalid_fd_negative not ok 12 mount_setattr_idmapped.invalid_fd_negative
The code creates a 100,000 byte tmpfs:
ASSERT_EQ(mount("testing", "/mnt", "tmpfs", MS_NOATIME | MS_NODEV, "size=100000,mode=700"), 0);
And then a little later creates a 2MB ext4 filesystem in that tmpfs:
ASSERT_EQ(ftruncate(img_fd, 1024 * 2048), 0); ASSERT_EQ(system("mkfs.ext4 -q /mnt/C/ext4.img"), 0);
At first glance it seems like that should never work, after all 2MB is larger than 100,000 bytes. However the filesystem image doesn't actually occupy 2MB on "disk" (actually RAM, due to tmpfs). On 4K kernels the ext4.img uses ~84KB of actual space (according to du), which just fits.
However on 64K PAGE_SIZE kernels the ext4.img takes at least 256KB, which is too large to fit in the tmpfs, hence the errors.
It seems fraught to rely on the ext4.img taking less space on disk than the allocated size, so instead create the tmpfs with a size of 2MB. With that all 21 tests pass on 64K PAGE_SIZE kernels.
Fixes: 01eadc8dd96d ("tests: add mount_setattr() selftests") Signed-off-by: Michael Ellerman mpe@ellerman.id.au Link: https://lore.kernel.org/r/20241115134114.1219555-1-mpe@ellerman.id.au Reviewed-by: Ritesh Harjani (IBM) ritesh.list@gmail.com Signed-off-by: Christian Brauner brauner@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- tools/testing/selftests/mount_setattr/mount_setattr_test.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/testing/selftests/mount_setattr/mount_setattr_test.c b/tools/testing/selftests/mount_setattr/mount_setattr_test.c index c6a8c732b8021..304e6422a1f1c 100644 --- a/tools/testing/selftests/mount_setattr/mount_setattr_test.c +++ b/tools/testing/selftests/mount_setattr/mount_setattr_test.c @@ -1026,7 +1026,7 @@ FIXTURE_SETUP(mount_setattr_idmapped) "size=100000,mode=700"), 0);
ASSERT_EQ(mount("testing", "/mnt", "tmpfs", MS_NOATIME | MS_NODEV, - "size=100000,mode=700"), 0); + "size=2m,mode=700"), 0);
ASSERT_EQ(mkdir("/mnt/A", 0777), 0);