diff options
| author | FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> | 2008-07-16 20:33:35 +0200 |
|---|---|---|
| committer | Bartlomiej Zolnierkiewicz <bzolnier@gmail.com> | 2008-07-16 20:33:35 +0200 |
| commit | 0b6abc17700a7843b165c677da0ac94522f83083 (patch) | |
| tree | c347a4a03941731e4df26196fb52feb7492fac23 /drivers | |
| parent | 84e0f3f6c1e26588fdcb9f1b0f99d0275229bc99 (diff) | |
ide: avoid DMA on the stack for REQ_TYPE_ATA_PC
Some REQ_TYPE_ATA_PC commands uses the stack buffers for DMA, which
leads to memory corruption on a non-coherent platform.
With regard to alignment and padding, ide-cd has the the dma safe
check for sg requests and REQ_TYPE_ATA_PC. This adds the stack buffer
check to that check.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Borislav Petkov <petkovbb@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Tejun Heo <htejun@gmail.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/ide/ide-cd.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/drivers/ide/ide-cd.c b/drivers/ide/ide-cd.c index d99847157186..d6667c36568c 100644 --- a/drivers/ide/ide-cd.c +++ b/drivers/ide/ide-cd.c @@ -1195,6 +1195,7 @@ static ide_startstop_t cdrom_do_block_pc(ide_drive_t *drive, struct request *rq) int mask = drive->queue->dma_alignment; unsigned long addr = (unsigned long)page_address(bio_page(rq->bio)); + unsigned long stack_mask = ~(THREAD_SIZE - 1); info->dma = drive->using_dma; @@ -1206,6 +1207,10 @@ static ide_startstop_t cdrom_do_block_pc(ide_drive_t *drive, struct request *rq) */ if ((rq->data_len & 15) || (addr & mask)) info->dma = 0; + + if (!((addr & stack_mask) ^ + ((unsigned long)current->stack & stack_mask))) + info->dma = 0; } /* start sending the command to the drive */ |