[SCSI] advansys: fix overrun_buf aligned bug

struct asc_dvc_var needs overrun buffer to be placed on an 8 byte
boundary. advansys defines struct asc_dvc_var:

struct asc_dvc_var {
	...
	uchar overrun_buf[ASC_OVERRUN_BSIZE] __aligned(8);

The problem is that struct asc_dvc_var is placed on
shost->hostdata. So if the hostdata is not on an 8 byte boundary, the
advansys crashes. The hostdata is placed on a sizeof(unsigned long)
boundary so the 8 byte boundary is not garanteed with x86_32.

With 2.6.23 and 2.6.24, the hostdata is on an 8 byte boundary by
chance, but with the current git, it's not.

This patch removes overrun_buf static array and use kzalloc.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

diff --git a/drivers/scsi/advansys.c b/drivers/scsi/advansys.c
index ccef891..3c2d688 100644 (file)
--- a/drivers/scsi/advansys.c
+++ b/drivers/scsi/advansys.c
@@ -566,7 +566,7 @@ typedef struct asc_dvc_var {
        ASC_SCSI_BIT_ID_TYPE unit_not_ready;
        ASC_SCSI_BIT_ID_TYPE queue_full_or_busy;
        ASC_SCSI_BIT_ID_TYPE start_motor;
-       uchar overrun_buf[ASC_OVERRUN_BSIZE] __aligned(8);
+       uchar *overrun_buf;
        dma_addr_t overrun_dma;
        uchar scsi_reset_wait;
        uchar chip_no;
@@ -13833,6 +13833,12 @@ static int __devinit advansys_board_found(struct Scsi_Host *shost,
         */
        if (ASC_NARROW_BOARD(boardp)) {
                ASC_DBG(2, "AscInitAsc1000Driver()\n");
+
+               asc_dvc_varp->overrun_buf = kzalloc(ASC_OVERRUN_BSIZE, GFP_KERNEL);
+               if (!asc_dvc_varp->overrun_buf) {
+                       ret = -ENOMEM;
+                       goto err_free_wide_mem;
+               }
                warn_code = AscInitAsc1000Driver(asc_dvc_varp);
 
                if (warn_code || asc_dvc_varp->err_code) {
@@ -13840,8 +13846,10 @@ static int __devinit advansys_board_found(struct Scsi_Host *shost,
                                        "warn 0x%x, error 0x%x\n",
                                        asc_dvc_varp->init_state, warn_code,
                                        asc_dvc_varp->err_code);
-                       if (asc_dvc_varp->err_code)
+                       if (asc_dvc_varp->err_code) {
                                ret = -ENODEV;
+                               kfree(asc_dvc_varp->overrun_buf);
+                       }
                }
        } else {
                if (advansys_wide_init_chip(shost))
@@ -13894,6 +13902,7 @@ static int advansys_release(struct Scsi_Host *shost)
                dma_unmap_single(board->dev,
                                        board->dvc_var.asc_dvc_var.overrun_dma,
                                        ASC_OVERRUN_BSIZE, DMA_FROM_DEVICE);
+               kfree(board->dvc_var.asc_dvc_var.overrun_buf);
        } else {
                iounmap(board->ioremap_addr);
                advansys_wide_free_mem(board);