4.18-stable review patch. If anyone has any objections, please let me know.
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From: Toshi Kani toshi.kani@hpe.com
commit cce6c9f7e6029caee45c459db5b3e78fec6973cb upstream.
Sync syscall to DAX file needs to flush processor cache, but it currently does not flush to existing DAX files. This is because 'ext4_da_aops' is set to address_space_operations of existing DAX files, instead of 'ext4_dax_aops', since S_DAX flag is set after ext4_set_aops() in the open path.
New file -------- lookup_open ext4_create __ext4_new_inode ext4_set_inode_flags // Set S_DAX flag ext4_set_aops // Set aops to ext4_dax_aops
Existing file ------------- lookup_open ext4_lookup ext4_iget ext4_set_aops // Set aops to ext4_da_aops ext4_set_inode_flags // Set S_DAX flag
Change ext4_iget() to initialize i_flags before ext4_set_aops().
Fixes: 5f0663bb4a64 ("ext4, dax: introduce ext4_dax_aops") Signed-off-by: Toshi Kani toshi.kani@hpe.com Signed-off-by: Theodore Ts'o tytso@mit.edu Suggested-by: Jan Kara jack@suse.cz Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/ext4/inode.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -4861,6 +4861,7 @@ struct inode *ext4_iget(struct super_blo * not initialized on a new filesystem. */ } ei->i_flags = le32_to_cpu(raw_inode->i_flags); + ext4_set_inode_flags(inode); inode->i_blocks = ext4_inode_blocks(raw_inode, ei); ei->i_file_acl = le32_to_cpu(raw_inode->i_file_acl_lo); if (ext4_has_feature_64bit(sb)) @@ -5010,7 +5011,6 @@ struct inode *ext4_iget(struct super_blo goto bad_inode; } brelse(iloc.bh); - ext4_set_inode_flags(inode);
unlock_new_inode(inode); return inode;