FAILED: patch "[PATCH] mtd: rawnand: stm32_fmc2: avoid overlapping mappings on ECC" failed to apply to 5.10-stable tree

gregkh
2025-09-13T12:23:23Z

The patch below does not apply to the 5.10-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x 513c40e59d5a414ab763a9c84797534b5e8c208d
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2025091309-quote-graves-e875@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^..

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 513c40e59d5a414ab763a9c84797534b5e8c208d Mon Sep 17 00:00:00 2001
From: Christophe Kerello <christophe.kerello@foss.st.com>
Date: Tue, 12 Aug 2025 09:26:58 +0200
Subject: [PATCH] mtd: rawnand: stm32_fmc2: avoid overlapping mappings on ECC
buffer

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")
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

diff --git a/drivers/mtd/nand/raw/stm32_fmc2_nand.c b/drivers/mtd/nand/raw/stm32_fmc2_nand.c
index a960403081f1..222c3c3b6848 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;