Re: [PATCH v14 03/15] fat: Implement fileattr_get for case sensitivity

["Chuck Lever" <cel@kernel.org>]

On Wed, May 20, 2026, at 10:31 AM, Mark Brown wrote:
> On Thu, May 07, 2026 at 04:52:56AM -0400, Chuck Lever wrote:
>> From: Chuck Lever <chuck.lever@oracle.com>
>> 
>> Report FAT's case sensitivity behavior via the FS_XFLAG_CASEFOLD
>> and FS_XFLAG_CASENONPRESERVING flags. FAT filesystems are
>> case-insensitive by default.
>> 
>> MSDOS supports a 'nocase' mount option that enables case-sensitive
>> behavior; check this option when reporting case sensitivity.
>> 
>> VFAT long filename entries preserve case; without VFAT, only
>> uppercased 8.3 short names are stored. MSDOS with 'nocase' also
>> preserves case since the name-formatting code skips upcasing when
>> 'nocase' is set. Check both options when reporting case preservation.
>
> I'm seeing a regression in -next with the LTP statx04 test which bisects
> to this commit:
>
> tst_tmpdir.c:316: TINFO: Using /tmp/LTP_sta8hUyB4 as tmpdir (tmpfs 
> filesystem)
> tst_device.c:98: TINFO: Found free device 0 '/dev/loop0'
> tst_test.c:2047: TINFO: LTP version: 20260130
> tst_test.c:2050: TINFO: Tested kernel: 7.1.0-rc4-next-20260520 #1 SMP 
> PREEMPT @1779279361 aarch64
>
> ...
>
> tst_test.c:1985: TINFO: === Testing on vfat ===
> tst_test.c:1290: TINFO: Formatting /dev/loop0 with vfat opts='' extra 
> opts=''
> tst_test.c:1302: TINFO: Mounting /dev/loop0 to 
> /tmp/LTP_sta8hUyB4/mntpoint fstyp=vfat flags=0
> statx04.c:121: TFAIL: STATX_ATTR_COMPRESSED not supported
> statx04.c:121: TFAIL: STATX_ATTR_APPEND not supported
> statx04.c:121: TFAIL: STATX_ATTR_IMMUTABLE not supported
> statx04.c:121: TFAIL: STATX_ATTR_NODUMP not supported

At first blush, that does not seem like a plausible bisect
result. This commit shouldn't affect the behavior of tmpfs
in any way.


-- 
Chuck Lever