Use dax_is_supported() to validate whether the architecture has
virtually aliased data caches at mount time. Print an error and disable
DAX if dax=always is requested as a mount option on an architecture
which does not support DAX.
This is relevant for architectures which require a dynamic check
to validate whether they have virtually aliased data caches.
Fixes: d92576f1167c ("dax: does not work correctly with virtual aliasing
caches")
Signed-off-by: Mathieu Desnoyers <mathieu.desnoy...@efficios.com>
Cc: Jan Kara <j...@suse.com>
Cc: linux-e...@vger.kernel.org
Cc: Andrew Morton <a...@linux-foundation.org>
Cc: Linus Torvalds <torva...@linux-foundation.org>
Cc: linux...@kvack.org
Cc: linux-a...@vger.kernel.org
Cc: Dan Williams <dan.j.willi...@intel.com>
Cc: Vishal Verma <vishal.l.ve...@intel.com>
Cc: Dave Jiang <dave.ji...@intel.com>
Cc: Matthew Wilcox <wi...@infradead.org>
Cc: Arnd Bergmann <a...@arndb.de>
Cc: Russell King <li...@armlinux.org.uk>
Cc: nvd...@lists.linux.dev
Cc: linux-...@vger.kernel.org
Cc: linux-fsde...@vger.kernel.org
---
fs/ext2/super.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/fs/ext2/super.c b/fs/ext2/super.c
index 01f9addc8b1f..30ff57d47ed4 100644
--- a/fs/ext2/super.c
+++ b/fs/ext2/super.c
@@ -955,7 +955,11 @@ static int ext2_fill_super(struct super_block *sb, void
*data, int silent)
blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
if (test_opt(sb, DAX)) {
- if (!sbi->s_daxdev) {
+ if (!dax_is_supported()) {
+ ext2_msg(sb, KERN_ERR,
+ "DAX unsupported by architecture. Turning off
DAX.");
+ clear_opt(sbi->s_mount_opt, DAX);
+ } else if (!sbi->s_daxdev) {
ext2_msg(sb, KERN_ERR,
"DAX unsupported by block device. Turning off
DAX.");
clear_opt(sbi->s_mount_opt, DAX);
--
2.39.2
