From 77409c4cdc44560e1b3b839e62d7f73478199680 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Fri, 2 Nov 2018 16:44:13 +0100 Subject: [PATCH] scsi: myrs: avoid stack overflow warning Putting a 1024 byte data structure on the stack is generally a bad idea. On 32-bit systems, it also triggers a compile-time warning when building with -Og: drivers/scsi/myrs.c: In function 'myrs_get_ctlr_info': drivers/scsi/myrs.c:212:1: error: the frame size of 1028 bytes is larger than 1024 bytes [-Werror=frame-larger-than=] We only really need three members of the structure, so just read them manually here instead of copying the entire structure. Fixes: 77266186397c ("scsi: myrs: Add Mylex RAID controller (SCSI interface)") Signed-off-by: Arnd Bergmann Reviewed-by: Hannes Reinecke Signed-off-by: Martin K. Petersen --- drivers/scsi/myrs.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/drivers/scsi/myrs.c b/drivers/scsi/myrs.c index 0264a2e2bc19..b8d54ef8cf6d 100644 --- a/drivers/scsi/myrs.c +++ b/drivers/scsi/myrs.c @@ -163,9 +163,12 @@ static unsigned char myrs_get_ctlr_info(struct myrs_hba *cs) dma_addr_t ctlr_info_addr; union myrs_sgl *sgl; unsigned char status; - struct myrs_ctlr_info old; + unsigned short ldev_present, ldev_critical, ldev_offline; + + ldev_present = cs->ctlr_info->ldev_present; + ldev_critical = cs->ctlr_info->ldev_critical; + ldev_offline = cs->ctlr_info->ldev_offline; - memcpy(&old, cs->ctlr_info, sizeof(struct myrs_ctlr_info)); ctlr_info_addr = dma_map_single(&cs->pdev->dev, cs->ctlr_info, sizeof(struct myrs_ctlr_info), DMA_FROM_DEVICE); @@ -198,9 +201,9 @@ static unsigned char myrs_get_ctlr_info(struct myrs_hba *cs) cs->ctlr_info->rbld_active + cs->ctlr_info->exp_active != 0) cs->needs_update = true; - if (cs->ctlr_info->ldev_present != old.ldev_present || - cs->ctlr_info->ldev_critical != old.ldev_critical || - cs->ctlr_info->ldev_offline != old.ldev_offline) + if (cs->ctlr_info->ldev_present != ldev_present || + cs->ctlr_info->ldev_critical != ldev_critical || + cs->ctlr_info->ldev_offline != ldev_offline) shost_printk(KERN_INFO, cs->host, "Logical drive count changes (%d/%d/%d)\n", cs->ctlr_info->ldev_critical, -- 2.30.2