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From: Linus Walleij <linus.walleij@linaro.org>
Date: Tue, 20 Feb 2024 23:58:45 +0100
Subject: [PATCH] mmc: sh_mmcif: sg_miter does not need to be atomic
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Message-Id: <20240220-fix-sh-mmcif-v1-1-b9d08a787c1f@linaro.org>
To: Ulf Hansson <ulf.hansson@linaro.org>
Cc: linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org, 
 Geert Uytterhoeven <geert@linux-m68k.org>, 
 Linus Walleij <linus.walleij@linaro.org>

All the sglist iterations happen in the *threaded* interrupt handler
and that context is not atomic, so don't request an atomic
sglist miter. Using an atomic miter results in "BUG: scheduling while
atomic" splats.

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Fixes: 27b57277d9ba ("mmc: sh_mmcif: Use sg_miter for PIO")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
Hi Geert, it'd be great if you could test this!
---
 drivers/mmc/host/sh_mmcif.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/mmc/host/sh_mmcif.c b/drivers/mmc/host/sh_mmcif.c
index 1ef6e153e5a3..669555b5e8fa 100644
--- a/drivers/mmc/host/sh_mmcif.c
+++ b/drivers/mmc/host/sh_mmcif.c
@@ -607,7 +607,7 @@ static void sh_mmcif_single_read(struct sh_mmcif_host *host,
 			   BLOCK_SIZE_MASK) + 3;
 
 	sg_miter_start(&host->sg_miter, data->sg, data->sg_len,
-		       SG_MITER_ATOMIC | SG_MITER_TO_SG);
+		       SG_MITER_TO_SG);
 
 	host->wait_for = MMCIF_WAIT_FOR_READ;
 
@@ -662,7 +662,7 @@ static void sh_mmcif_multi_read(struct sh_mmcif_host *host,
 		BLOCK_SIZE_MASK;
 
 	sg_miter_start(&host->sg_miter, data->sg, data->sg_len,
-		       SG_MITER_ATOMIC | SG_MITER_TO_SG);
+		       SG_MITER_TO_SG);
 
 	host->wait_for = MMCIF_WAIT_FOR_MREAD;
 
@@ -710,7 +710,7 @@ static void sh_mmcif_single_write(struct sh_mmcif_host *host,
 			   BLOCK_SIZE_MASK) + 3;
 
 	sg_miter_start(&host->sg_miter, data->sg, data->sg_len,
-		       SG_MITER_ATOMIC | SG_MITER_FROM_SG);
+		       SG_MITER_FROM_SG);
 
 	host->wait_for = MMCIF_WAIT_FOR_WRITE;
 
@@ -765,7 +765,7 @@ static void sh_mmcif_multi_write(struct sh_mmcif_host *host,
 		BLOCK_SIZE_MASK;
 
 	sg_miter_start(&host->sg_miter, data->sg, data->sg_len,
-		       SG_MITER_ATOMIC | SG_MITER_FROM_SG);
+		       SG_MITER_FROM_SG);
 
 	host->wait_for = MMCIF_WAIT_FOR_MWRITE;
 

---
base-commit: 2d5c7b7eb345249cb34d42cbc2b97b4c57ea944e
change-id: 20240220-fix-sh-mmcif-49c1de70c5b7

Best regards,
-- 
Linus Walleij <linus.walleij@linaro.org>