dma: dw-edma: Fix build warning in dw_edma_pcie_probe()

The function dw_edma_pcie_probe() in dw-edma-pcie.c triggered a
frame size warning:
ld.lld:warning:
  drivers/dma/dw-edma/dw-edma-pcie.c:162:0: stack frame size (1040) exceeds limit (1024) in function 'dw_edma_pcie_probe'

This patch reduces the stack usage by dynamically allocating the
`vsec_data` structure using kmalloc(), rather than placing it on
the stack. This eliminates the overflow warning and improves kernel
robustness.

Signed-off-by: Abinash Singh <abinashsinghlalotra@gmail.com>
Acked-by: Manivannan Sadhasivam <mani@kernel.org>
Link: https://lore.kernel.org/r/20250705160055.808165-1-abinashsinghlalotra@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

diff --git a/drivers/dma/dw-edma/dw-edma-pcie.c b/drivers/dma/dw-edma/dw-edma-pcie.c
index 49f09998e5c0ddffa3311a20ef78ebddc819a8b1..3371e0a76d3ca155de36134a51a852fd7c2b2b02 100644 (file)
--- a/drivers/dma/dw-edma/dw-edma-pcie.c
+++ b/drivers/dma/dw-edma/dw-edma-pcie.c
@@ -161,12 +161,16 @@ static int dw_edma_pcie_probe(struct pci_dev *pdev,
                              const struct pci_device_id *pid)
 {
        struct dw_edma_pcie_data *pdata = (void *)pid->driver_data;
-       struct dw_edma_pcie_data vsec_data;
+       struct dw_edma_pcie_data *vsec_data __free(kfree) = NULL;
        struct device *dev = &pdev->dev;
        struct dw_edma_chip *chip;
        int err, nr_irqs;
        int i, mask;
 
+       vsec_data = kmalloc(sizeof(*vsec_data), GFP_KERNEL);
+       if (!vsec_data)
+               return -ENOMEM;
+
        /* Enable PCI device */
        err = pcim_enable_device(pdev);
        if (err) {
@@ -174,23 +178,23 @@ static int dw_edma_pcie_probe(struct pci_dev *pdev,
                return err;
        }
 
-       memcpy(&vsec_data, pdata, sizeof(struct dw_edma_pcie_data));
+       memcpy(vsec_data, pdata, sizeof(struct dw_edma_pcie_data));
 
        /*
         * Tries to find if exists a PCIe Vendor-Specific Extended Capability
         * for the DMA, if one exists, then reconfigures it.
         */
-       dw_edma_pcie_get_vsec_dma_data(pdev, &vsec_data);
+       dw_edma_pcie_get_vsec_dma_data(pdev, vsec_data);
 
        /* Mapping PCI BAR regions */
-       mask = BIT(vsec_data.rg.bar);
-       for (i = 0; i < vsec_data.wr_ch_cnt; i++) {
-               mask |= BIT(vsec_data.ll_wr[i].bar);
-               mask |= BIT(vsec_data.dt_wr[i].bar);
+       mask = BIT(vsec_data->rg.bar);
+       for (i = 0; i < vsec_data->wr_ch_cnt; i++) {
+               mask |= BIT(vsec_data->ll_wr[i].bar);
+               mask |= BIT(vsec_data->dt_wr[i].bar);
        }
-       for (i = 0; i < vsec_data.rd_ch_cnt; i++) {
-               mask |= BIT(vsec_data.ll_rd[i].bar);
-               mask |= BIT(vsec_data.dt_rd[i].bar);
+       for (i = 0; i < vsec_data->rd_ch_cnt; i++) {
+               mask |= BIT(vsec_data->ll_rd[i].bar);
+               mask |= BIT(vsec_data->dt_rd[i].bar);
        }
        err = pcim_iomap_regions(pdev, mask, pci_name(pdev));
        if (err) {
@@ -213,7 +217,7 @@ static int dw_edma_pcie_probe(struct pci_dev *pdev,
                return -ENOMEM;
 
        /* IRQs allocation */
-       nr_irqs = pci_alloc_irq_vectors(pdev, 1, vsec_data.irqs,
+       nr_irqs = pci_alloc_irq_vectors(pdev, 1, vsec_data->irqs,
                                        PCI_IRQ_MSI | PCI_IRQ_MSIX);
        if (nr_irqs < 1) {
                pci_err(pdev, "fail to alloc IRQ vector (number of IRQs=%u)\n",
@@ -224,22 +228,22 @@ static int dw_edma_pcie_probe(struct pci_dev *pdev,
        /* Data structure initialization */
        chip->dev = dev;
 
-       chip->mf = vsec_data.mf;
+       chip->mf = vsec_data->mf;
        chip->nr_irqs = nr_irqs;
        chip->ops = &dw_edma_pcie_plat_ops;
 
-       chip->ll_wr_cnt = vsec_data.wr_ch_cnt;
-       chip->ll_rd_cnt = vsec_data.rd_ch_cnt;
+       chip->ll_wr_cnt = vsec_data->wr_ch_cnt;
+       chip->ll_rd_cnt = vsec_data->rd_ch_cnt;
 
-       chip->reg_base = pcim_iomap_table(pdev)[vsec_data.rg.bar];
+       chip->reg_base = pcim_iomap_table(pdev)[vsec_data->rg.bar];
        if (!chip->reg_base)
                return -ENOMEM;
 
        for (i = 0; i < chip->ll_wr_cnt; i++) {
                struct dw_edma_region *ll_region = &chip->ll_region_wr[i];
                struct dw_edma_region *dt_region = &chip->dt_region_wr[i];
-               struct dw_edma_block *ll_block = &vsec_data.ll_wr[i];
-               struct dw_edma_block *dt_block = &vsec_data.dt_wr[i];
+               struct dw_edma_block *ll_block = &vsec_data->ll_wr[i];
+               struct dw_edma_block *dt_block = &vsec_data->dt_wr[i];
 
                ll_region->vaddr.io = pcim_iomap_table(pdev)[ll_block->bar];
                if (!ll_region->vaddr.io)
@@ -263,8 +267,8 @@ static int dw_edma_pcie_probe(struct pci_dev *pdev,
        for (i = 0; i < chip->ll_rd_cnt; i++) {
                struct dw_edma_region *ll_region = &chip->ll_region_rd[i];
                struct dw_edma_region *dt_region = &chip->dt_region_rd[i];
-               struct dw_edma_block *ll_block = &vsec_data.ll_rd[i];
-               struct dw_edma_block *dt_block = &vsec_data.dt_rd[i];
+               struct dw_edma_block *ll_block = &vsec_data->ll_rd[i];
+               struct dw_edma_block *dt_block = &vsec_data->dt_rd[i];
 
                ll_region->vaddr.io = pcim_iomap_table(pdev)[ll_block->bar];
                if (!ll_region->vaddr.io)
@@ -298,31 +302,31 @@ static int dw_edma_pcie_probe(struct pci_dev *pdev,
                pci_dbg(pdev, "Version:\tUnknown (0x%x)\n", chip->mf);
 
        pci_dbg(pdev, "Registers:\tBAR=%u, off=0x%.8lx, sz=0x%zx bytes, addr(v=%p)\n",
-               vsec_data.rg.bar, vsec_data.rg.off, vsec_data.rg.sz,
+               vsec_data->rg.bar, vsec_data->rg.off, vsec_data->rg.sz,
                chip->reg_base);
 
 
        for (i = 0; i < chip->ll_wr_cnt; i++) {
                pci_dbg(pdev, "L. List:\tWRITE CH%.2u, BAR=%u, off=0x%.8lx, sz=0x%zx bytes, addr(v=%p, p=%pa)\n",
-                       i, vsec_data.ll_wr[i].bar,
-                       vsec_data.ll_wr[i].off, chip->ll_region_wr[i].sz,
+                       i, vsec_data->ll_wr[i].bar,
+                       vsec_data->ll_wr[i].off, chip->ll_region_wr[i].sz,
                        chip->ll_region_wr[i].vaddr.io, &chip->ll_region_wr[i].paddr);
 
                pci_dbg(pdev, "Data:\tWRITE CH%.2u, BAR=%u, off=0x%.8lx, sz=0x%zx bytes, addr(v=%p, p=%pa)\n",
-                       i, vsec_data.dt_wr[i].bar,
-                       vsec_data.dt_wr[i].off, chip->dt_region_wr[i].sz,
+                       i, vsec_data->dt_wr[i].bar,
+                       vsec_data->dt_wr[i].off, chip->dt_region_wr[i].sz,
                        chip->dt_region_wr[i].vaddr.io, &chip->dt_region_wr[i].paddr);
        }
 
        for (i = 0; i < chip->ll_rd_cnt; i++) {
                pci_dbg(pdev, "L. List:\tREAD CH%.2u, BAR=%u, off=0x%.8lx, sz=0x%zx bytes, addr(v=%p, p=%pa)\n",
-                       i, vsec_data.ll_rd[i].bar,
-                       vsec_data.ll_rd[i].off, chip->ll_region_rd[i].sz,
+                       i, vsec_data->ll_rd[i].bar,
+                       vsec_data->ll_rd[i].off, chip->ll_region_rd[i].sz,
                        chip->ll_region_rd[i].vaddr.io, &chip->ll_region_rd[i].paddr);
 
                pci_dbg(pdev, "Data:\tREAD CH%.2u, BAR=%u, off=0x%.8lx, sz=0x%zx bytes, addr(v=%p, p=%pa)\n",
-                       i, vsec_data.dt_rd[i].bar,
-                       vsec_data.dt_rd[i].off, chip->dt_region_rd[i].sz,
+                       i, vsec_data->dt_rd[i].bar,
+                       vsec_data->dt_rd[i].off, chip->dt_region_rd[i].sz,
                        chip->dt_region_rd[i].vaddr.io, &chip->dt_region_rd[i].paddr);
        }