[PATCH v1] scsi: Enable FUA bit and remove per-write SYNC_CACHE operations

[Balaji Selvanathan]

Hi Casey, Tom,

On 1/16/2026 11:19 PM, Casey Connolly wrote:
> On 1/16/26 16:57, Tom Rini wrote:
>> On Mon, Jan 05, 2026 at 10:55:26AM +0530, Balaji Selvanathan wrote:
>>
>>> Enable the Force Unit Access (FUA) bit in SCSI WRITE10 commands to
>>> ensure writes bypass the device's volatile cache and go directly to
>>> non-volatile storage. This provides write-through behavior without
>>> requiring explicit cache flushes after each write operation.
>>>
>>> Remove the SYNC_CACHE command that was being issued after every
>>> scsi_write() call, as it is redundant when FUA is enabled and was
>>> causing system hangs during large sparse image flashing operations.
>>>
>>> Signed-off-by: Aswin Murugan <aswin.murugan at oss.qualcomm.com>
>>> Signed-off-by: Balaji Selvanathan <balaji.selvanathan at oss.qualcomm.com>
>>
>> This introduces failure to build on xilinx_zynqmp_virt and others:
>> drivers/scsi/scsi.c:85:13: error: 'scsi_setup_sync_cache' defined but 
>> not used [-Werror=unused-function]
>
> Balaji,
>
> The patch introducing explicit SYNC_CACHE made quite a few more 
> changes, I would recommend including a full revert of that in your 
> patch (and properly referencing the commit in question!).

Did a full revert of the "scsi: sync cache on write" commit and then did 
the FUA bit change in this v2: 
https://lore.kernel.org/u-boot/20260122083954.2722972-1-balaji.selvanathan@oss.qualcomm.com/

Thanks,

Balaji

>
> Kind regards,
> - Casey
>
>>
>