Avoid below overlapping mappings by using a contiguous non-cacheable buffer.

[ 4.077708] DMA-API: stm32_fmc2_nfc 48810000.nand-controller: cacheline tracking EEXIST, overlapping mappings aren't supported [ 4.089103] WARNING: CPU: 1 PID: 44 at kernel/dma/debug.c:568 add_dma_entry+0x23c/0x300 [ 4.097071] Modules linked in: [ 4.100101] CPU: 1 PID: 44 Comm: kworker/u4:2 Not tainted 6.1.82 #1 [ 4.106346] Hardware name: STMicroelectronics STM32MP257F VALID1 SNOR / MB1704 (LPDDR4 Power discrete) + MB1703 + MB1708 (SNOR MB1730) (DT) [ 4.118824] Workqueue: events_unbound deferred_probe_work_func [ 4.124674] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 4.131624] pc : add_dma_entry+0x23c/0x300 [ 4.135658] lr : add_dma_entry+0x23c/0x300 [ 4.139792] sp : ffff800009dbb490 [ 4.143016] x29: ffff800009dbb4a0 x28: 0000000004008022 x27: ffff8000098a6000 [ 4.150174] x26: 0000000000000000 x25: ffff8000099e7000 x24: ffff8000099e7de8 [ 4.157231] x23: 00000000ffffffff x22: 0000000000000000 x21: ffff8000098a6a20 [ 4.164388] x20: ffff000080964180 x19: ffff800009819ba0 x18: 0000000000000006 [ 4.171545] x17: 6361727420656e69 x16: 6c6568636163203a x15: 72656c6c6f72746e [ 4.178602] x14: 6f632d646e616e2e x13: ffff800009832f58 x12: 00000000000004ec [ 4.185759] x11: 00000000000001a4 x10: ffff80000988af58 x9 : ffff800009832f58 [ 4.192916] x8 : 00000000ffffefff x7 : ffff80000988af58 x6 : 80000000fffff000 [ 4.199972] x5 : 000000000000bff4 x4 : 0000000000000000 x3 : 0000000000000000 [ 4.207128] x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff0000812d2c40 [ 4.214185] Call trace: [ 4.216605] add_dma_entry+0x23c/0x300 [ 4.220338] debug_dma_map_sg+0x198/0x350 [ 4.224373] __dma_map_sg_attrs+0xa0/0x110 [ 4.228411] dma_map_sg_attrs+0x10/0x2c [ 4.232247] stm32_fmc2_nfc_xfer.isra.0+0x1c8/0x3fc [ 4.237088] stm32_fmc2_nfc_seq_read_page+0xc8/0x174 [ 4.242127] nand_read_oob+0x1d4/0x8e0 [ 4.245861] mtd_read_oob_std+0x58/0x84 [ 4.249596] mtd_read_oob+0x90/0x150 [ 4.253231] mtd_read+0x68/0xac

Signed-off-by: Christophe Kerello christophe.kerello@foss.st.com Cc: stable@vger.kernel.org Fixes: 2cd457f328c1 ("mtd: rawnand: stm32_fmc2: add STM32 FMC2 NAND flash controller driver") --- drivers/mtd/nand/raw/stm32_fmc2_nand.c | 28 +++++++++------------------- 1 file changed, 9 insertions(+), 19 deletions(-)

diff --git a/drivers/mtd/nand/raw/stm32_fmc2_nand.c b/drivers/mtd/nand/raw/stm32_fmc2_nand.c index a960403081f11091837b73b8610231fe421d0c05..222c3c3b684841879a55835e802dcf9983860c28 100644 --- a/drivers/mtd/nand/raw/stm32_fmc2_nand.c +++ b/drivers/mtd/nand/raw/stm32_fmc2_nand.c @@ -272,6 +272,7 @@ struct stm32_fmc2_nfc { struct sg_table dma_data_sg; struct sg_table dma_ecc_sg; u8 *ecc_buf; + dma_addr_t dma_ecc_addr; int dma_ecc_len; u32 tx_dma_max_burst; u32 rx_dma_max_burst; @@ -902,17 +903,10 @@ static int stm32_fmc2_nfc_xfer(struct nand_chip *chip, const u8 *buf,

if (!write_data && !raw) { /* Configure DMA ECC status */ - p = nfc->ecc_buf; for_each_sg(nfc->dma_ecc_sg.sgl, sg, eccsteps, s) { - sg_set_buf(sg, p, nfc->dma_ecc_len); - p += nfc->dma_ecc_len; - } - - ret = dma_map_sg(nfc->dev, nfc->dma_ecc_sg.sgl, - eccsteps, dma_data_dir); - if (!ret) { - ret = -EIO; - goto err_unmap_data; + sg_dma_address(sg) = nfc->dma_ecc_addr + + s * nfc->dma_ecc_len; + sg_dma_len(sg) = nfc->dma_ecc_len; }

desc_ecc = dmaengine_prep_slave_sg(nfc->dma_ecc_ch, @@ -921,7 +915,7 @@ static int stm32_fmc2_nfc_xfer(struct nand_chip *chip, const u8 *buf, DMA_PREP_INTERRUPT); if (!desc_ecc) { ret = -ENOMEM; - goto err_unmap_ecc; + goto err_unmap_data; }

reinit_completion(&nfc->dma_ecc_complete); @@ -929,7 +923,7 @@ static int stm32_fmc2_nfc_xfer(struct nand_chip *chip, const u8 *buf, desc_ecc->callback_param = &nfc->dma_ecc_complete; ret = dma_submit_error(dmaengine_submit(desc_ecc)); if (ret) - goto err_unmap_ecc; + goto err_unmap_data;

dma_async_issue_pending(nfc->dma_ecc_ch); } @@ -949,7 +943,7 @@ static int stm32_fmc2_nfc_xfer(struct nand_chip *chip, const u8 *buf, if (!write_data && !raw) dmaengine_terminate_all(nfc->dma_ecc_ch); ret = -ETIMEDOUT; - goto err_unmap_ecc; + goto err_unmap_data; }

/* Wait DMA data transfer completion */ @@ -969,11 +963,6 @@ static int stm32_fmc2_nfc_xfer(struct nand_chip *chip, const u8 *buf, } }

-err_unmap_ecc: - if (!write_data && !raw) - dma_unmap_sg(nfc->dev, nfc->dma_ecc_sg.sgl, - eccsteps, dma_data_dir); - err_unmap_data: dma_unmap_sg(nfc->dev, nfc->dma_data_sg.sgl, eccsteps, dma_data_dir);

@@ -1610,7 +1599,8 @@ static int stm32_fmc2_nfc_dma_setup(struct stm32_fmc2_nfc *nfc) return ret;

/* Allocate a buffer to store ECC status registers */ - nfc->ecc_buf = devm_kzalloc(nfc->dev, FMC2_MAX_ECC_BUF_LEN, GFP_KERNEL); + nfc->ecc_buf = dmam_alloc_coherent(nfc->dev, FMC2_MAX_ECC_BUF_LEN, + &nfc->dma_ecc_addr, GFP_KERNEL); if (!nfc->ecc_buf) return -ENOMEM;

--- base-commit: fb2fae70e7e985c4acb1ad96110d8b98bb64a87c change-id: 20250811-fix-dma-overlapping-1c8fba7fd519

Best regards,