diff options
author | Huacai Chen <chenhc@lemote.com> | 2017-11-21 16:23:39 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-12-16 12:33:48 +0300 |
commit | 7e0091c2951fa831992d2f00e4453951d84a58b6 (patch) | |
tree | 60a11a384f9adbef79d08492e3d64c577ce8aa1e /include | |
parent | 98448333588c4a516a44e31d3ffcce4c3406a3b7 (diff) | |
download | linux-7e0091c2951fa831992d2f00e4453951d84a58b6.tar.xz |
scsi: libsas: align sata_device's rps_resp on a cacheline
commit c2e8fbf908afd81ad502b567a6639598f92c9b9d upstream.
The rps_resp 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 SATA
device behind a SAS expander.
Fix this by ensuring that the rps_resp buffer is cacheline aligned.
This issue is similar to that fixed by Commit 84bda12af31f93 ("libata:
align ap->sector_buf") and Commit 4ee34ea3a12396f35b26 ("libata: Align
ata_device's id on a cacheline").
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include')
-rw-r--r-- | include/scsi/libsas.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/include/scsi/libsas.h b/include/scsi/libsas.h index dae99d7d2bc0..706a7017885c 100644 --- a/include/scsi/libsas.h +++ b/include/scsi/libsas.h @@ -165,11 +165,11 @@ struct expander_device { struct sata_device { unsigned int class; - struct smp_resp rps_resp; /* report_phy_sata_resp */ u8 port_no; /* port number, if this is a PM (Port) */ struct ata_port *ap; struct ata_host ata_host; + struct smp_resp rps_resp ____cacheline_aligned; /* report_phy_sata_resp */ u8 fis[ATA_RESP_FIS_SIZE]; }; |