android_kernel_motorola_sm6225/fs/ext2
Mikulas Patocka da0d5ccf84 ext2: don't update mtime on COW faults
commit 1ef6ea0efe8e68d0299dad44c39dc6ad9e5d1f39 upstream.

When running in a dax mode, if the user maps a page with MAP_PRIVATE and
PROT_WRITE, the ext2 filesystem would incorrectly update ctime and mtime
when the user hits a COW fault.

This breaks building of the Linux kernel.  How to reproduce:

 1. extract the Linux kernel tree on dax-mounted ext2 filesystem
 2. run make clean
 3. run make -j12
 4. run make -j12

at step 4, make would incorrectly rebuild the whole kernel (although it
was already built in step 3).

The reason for the breakage is that almost all object files depend on
objtool.  When we run objtool, it takes COW page fault on its .data
section, and these faults will incorrectly update the timestamp of the
objtool binary.  The updated timestamp causes make to rebuild the whole
tree.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-09 19:04:28 +02:00
..
acl.c
acl.h
balloc.c Rename superblock flags (MS_xyz -> SB_xyz) 2017-11-27 13:05:09 -08:00
dir.c iversion: Rename make inode_cmp_iversion{+raw} to inode_eq_iversion{+raw} 2018-02-01 08:15:25 -05:00
ext2.h ext2: add warning when specifying nocheck option 2018-06-20 11:04:26 +02:00
file.c ext2: don't update mtime on COW faults 2020-09-09 19:04:28 +02:00
ialloc.c ext2: fix missing percpu_counter_inc 2020-08-21 11:05:32 +02:00
inode.c ext2: check err when partial != NULL 2019-12-17 20:35:18 +01:00
ioctl.c
Kconfig fs/*/Kconfig: drop links to 404-compliant http://acl.bestbits.at 2018-01-01 12:45:37 -07:00
Makefile
namei.c ext2: make sure that partially set up inodes won't be returned by ext2_iget() 2018-08-03 16:03:31 -04:00
super.c ext2: Adjust indentation in ext2_fill_super 2020-02-11 04:34:12 -08:00
symlink.c
xattr.c ext2: fix debug reference to ext2_xattr_cache 2020-04-23 10:30:21 +02:00
xattr.h
xattr_security.c
xattr_trusted.c
xattr_user.c