scsi: megaraid_mbox: Reduce stack usage in megaraid_cmm_register()

The megaraid_cmm_register() function has a local copy of mraid_mmadp_t
on the stack that gets copied into the actual structure used at
runtime. When -fsanitize=thread is enabled, this causes the per-function
stack frame to grow beyond the warning limit:

megaraid_mbox.c: In function 'megaraid_cmm_register':
megaraid_mbox.c:3472:1: error: the frame size of 1312 bytes is larger than 1280 bytes [-Werror=frame-larger-than=]

Refactor this by moving the allocation into the caller to save the extra
on-stack copy of the structure.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patch.msgid.link/20260519202143.1305850-1-arnd@kernel.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/megaraid/megaraid_mbox.c b/drivers/scsi/megaraid/megaraid_mbox.c
index 06cf94ee4e360bfa1c89e4445aeb544404027c84..ce89032a5a744106729d67cc8fc4946d96a76635 100644 (file)
--- a/drivers/scsi/megaraid/megaraid_mbox.c
+++ b/drivers/scsi/megaraid/megaraid_mbox.c
@@ -3396,7 +3396,7 @@ static int
 megaraid_cmm_register(adapter_t *adapter)
 {
        mraid_device_t  *raid_dev = ADAP2RAIDDEV(adapter);
-       mraid_mmadp_t   adp;
+       mraid_mmadp_t   *adp;
        scb_t           *scb;
        mbox_ccb_t      *ccb;
        int             rval;
@@ -3404,11 +3404,16 @@ megaraid_cmm_register(adapter_t *adapter)
 
        // Allocate memory for the base list of scb for management module.
        adapter->uscb_list = kzalloc_objs(scb_t, MBOX_MAX_USER_CMDS);
+       adp = kzalloc_obj(*adp);
 
-       if (adapter->uscb_list == NULL) {
+       if (!adapter->uscb_list || !adp) {
                con_log(CL_ANN, (KERN_WARNING
                        "megaraid: out of memory, %s %d\n", __func__,
                        __LINE__));
+
+               kfree(adapter->uscb_list);
+               kfree(adp);
+
                return -1;
        }
 
@@ -3452,20 +3457,21 @@ megaraid_cmm_register(adapter_t *adapter)
                list_add_tail(&scb->list, &adapter->uscb_pool);
        }
 
-       adp.unique_id           = adapter->unique_id;
-       adp.drvr_type           = DRVRTYPE_MBOX;
-       adp.drvr_data           = (unsigned long)adapter;
-       adp.pdev                = adapter->pdev;
-       adp.issue_uioc          = megaraid_mbox_mm_handler;
-       adp.timeout             = MBOX_RESET_WAIT + MBOX_RESET_EXT_WAIT;
-       adp.max_kioc            = MBOX_MAX_USER_CMDS;
+       adp->unique_id          = adapter->unique_id;
+       adp->drvr_type          = DRVRTYPE_MBOX;
+       adp->drvr_data          = (unsigned long)adapter;
+       adp->pdev               = adapter->pdev;
+       adp->issue_uioc         = megaraid_mbox_mm_handler;
+       adp->timeout            = MBOX_RESET_WAIT + MBOX_RESET_EXT_WAIT;
+       adp->max_kioc           = MBOX_MAX_USER_CMDS;
 
-       if ((rval = mraid_mm_register_adp(&adp)) != 0) {
+       if ((rval = mraid_mm_register_adp(adp)) != 0) {
 
                con_log(CL_ANN, (KERN_WARNING
                        "megaraid mbox: did not register with CMM\n"));
 
                kfree(adapter->uscb_list);
+               kfree(adp);
        }
 
        return rval;

diff --git a/drivers/scsi/megaraid/megaraid_mm.c b/drivers/scsi/megaraid/megaraid_mm.c
index 538da0e98131a37eea7ea81a51cf9d083b726002..60db48dc8f3a4935e65f9ad8de0af72eb0c8ba41 100644 (file)
--- a/drivers/scsi/megaraid/megaraid_mm.c
+++ b/drivers/scsi/megaraid/megaraid_mm.c
@@ -898,42 +898,28 @@ hinfo_to_cinfo(mraid_hba_info_t *hinfo, mcontroller_t *cinfo)
 
 /**
  * mraid_mm_register_adp - Registration routine for low level drivers
- * @lld_adp    : Adapter object
+ * @adapter    : Adapter object
  */
 int
-mraid_mm_register_adp(mraid_mmadp_t *lld_adp)
+mraid_mm_register_adp(mraid_mmadp_t *adapter)
 {
-       mraid_mmadp_t   *adapter;
        mbox64_t        *mbox_list;
        uioc_t          *kioc;
        uint32_t        rval;
        int             i;
 
 
-       if (lld_adp->drvr_type != DRVRTYPE_MBOX)
+       if (adapter->drvr_type != DRVRTYPE_MBOX)
                return (-EINVAL);
 
-       adapter = kzalloc_obj(mraid_mmadp_t);
-
-       if (!adapter)
-               return -ENOMEM;
-
-
-       adapter->unique_id      = lld_adp->unique_id;
-       adapter->drvr_type      = lld_adp->drvr_type;
-       adapter->drvr_data      = lld_adp->drvr_data;
-       adapter->pdev           = lld_adp->pdev;
-       adapter->issue_uioc     = lld_adp->issue_uioc;
-       adapter->timeout        = lld_adp->timeout;
-       adapter->max_kioc       = lld_adp->max_kioc;
        adapter->quiescent      = 1;
 
        /*
         * Allocate single blocks of memory for all required kiocs,
         * mailboxes and passthru structures.
         */
-       adapter->kioc_list      = kmalloc_objs(uioc_t, lld_adp->max_kioc);
-       adapter->mbox_list      = kmalloc_objs(mbox64_t, lld_adp->max_kioc);
+       adapter->kioc_list      = kmalloc_objs(uioc_t, adapter->max_kioc);
+       adapter->mbox_list      = kmalloc_objs(mbox64_t, adapter->max_kioc);
        adapter->pthru_dma_pool = dma_pool_create("megaraid mm pthru pool",
                                                &adapter->pdev->dev,
                                                sizeof(mraid_passthru_t),
@@ -956,11 +942,11 @@ mraid_mm_register_adp(mraid_mmadp_t *lld_adp)
         */
        INIT_LIST_HEAD(&adapter->kioc_pool);
        spin_lock_init(&adapter->kioc_pool_lock);
-       sema_init(&adapter->kioc_semaphore, lld_adp->max_kioc);
+       sema_init(&adapter->kioc_semaphore, adapter->max_kioc);
 
        mbox_list       = (mbox64_t *)adapter->mbox_list;
 
-       for (i = 0; i < lld_adp->max_kioc; i++) {
+       for (i = 0; i < adapter->max_kioc; i++) {
 
                kioc            = adapter->kioc_list + i;
                kioc->cmdbuf    = (uint64_t)(unsigned long)(mbox_list + i);
@@ -997,7 +983,7 @@ dma_pool_error:
 
 pthru_dma_pool_error:
 
-       for (i = 0; i < lld_adp->max_kioc; i++) {
+       for (i = 0; i < adapter->max_kioc; i++) {
                kioc = adapter->kioc_list + i;
                if (kioc->pthru32) {
                        dma_pool_free(adapter->pthru_dma_pool, kioc->pthru32,