• Geert Uytterhoeven's avatar
    ata: sata_rcar: Fix DMA boundary mask · 67e326e4
    Geert Uytterhoeven authored
    commit df9c590986fdb6db9d5636d6cd93bc919c01b451 upstream.
    
    Before commit 9495b7e9 ("driver core: platform: Initialize
    dma_parms for platform devices"), the R-Car SATA device didn't have DMA
    parameters.  Hence the DMA boundary mask supplied by its driver was
    silently ignored, as __scsi_init_queue() doesn't check the return value
    of dma_set_seg_boundary(), and the default value of 0xffffffff was used.
    
    Now the device has gained DMA parameters, the driver-supplied value is
    used, and the following warning is printed on Salvator-XS:
    
        DMA-API: sata_rcar ee300000.sata: mapping sg segment across boundary [start=0x00000000ffffe000] [end=0x00000000ffffefff] [boundary=0x000000001ffffffe]
        WARNING: CPU: 5 PID: 38 at kernel/dma/debug.c:1233 debug_dma_map_sg+0x298/0x300
    
    (the range of start/end values depend on whether IOMMU support is
     enabled or not)
    
    The issue here is that SATA_RCAR_DMA_BOUNDARY doesn't have bit 0 set, so
    any typical end value, which is odd, will trigger the check.
    
    Fix this by increasing the DMA boundary value by 1.
    
    This also fixes the following WRITE DMA EXT timeout issue:
    
        # dd if=/dev/urandom of=/mnt/de1/file1-1024M bs=1M count=1024
        ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x6 frozen
        ata1.00: failed command: WRITE DMA EXT
        ata1.00: cmd 35/00:00:00:e6:0c/00:0a:00:00:00/e0 tag 0 dma 1310720 out
        res 40/00:01:00:00:00/00:00:00:00:00/00 Emask 0x4 (timeout)
        ata1.00: status: { DRDY }
    
    as seen by Shimoda-san since commit 429120f3 ("block: fix
    splitting segments on boundary masks").
    
    Fixes: 8bfbeed5 ("sata_rcar: correct 'sata_rcar_sht'")
    Fixes: 9495b7e9 ("driver core: platform: Initialize dma_parms for platform devices")
    Fixes: 429120f3
    
     ("block: fix splitting segments on boundary masks")
    Signed-off-by: default avatarGeert Uytterhoeven <geert+renesas@glider.be>
    Tested-by: default avatarLad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
    Tested-by: default avatarYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
    Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
    Reviewed-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
    Reviewed-by: default avatarSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
    Reviewed-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
    Cc: stable <stable@vger.kernel.org>
    Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
    Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
    67e326e4
sata_rcar.c 26.8 KB