libata: Align ata_device's id on a cacheline

commit 4ee34ea3a1 upstream.

The id buffer in ata_device is a DMA target, but it isn't explicitly
cacheline aligned. Due to this, adjacent fields can be overwritten with
stale data from memory on non coherent architectures. As a result, the
kernel is sometimes unable to communicate with an ATA device.

Fix this by ensuring that the id buffer is cacheline aligned.

This issue is similar to that fixed by Commit 84bda12af3
("libata: align ap->sector_buf").

Signed-off-by: Harvey Hunt <harvey.hunt@imgtec.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Harvey Hunt
2016-02-24 15:16:43 +00:00
committed by Greg Kroah-Hartman
parent b693f2ad0f
commit cea2cbff57

View File

@@ -718,7 +718,7 @@ struct ata_device {
union {
u16 id[ATA_ID_WORDS]; /* IDENTIFY xxx DEVICE data */
u32 gscr[SATA_PMP_GSCR_DWORDS]; /* PMP GSCR block */
};
} ____cacheline_aligned;
/* DEVSLP Timing Variables from Identify Device Data Log */
u8 devslp_timing[ATA_LOG_DEVSLP_SIZE];