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Subject[PATCH] mtd: rawnand: mxc: remove __init qualifier from mxcnd_probe_dt
Date
mxcnd_probe_dt is called from mxcnd_probe, which is not marked as __init.

Using the sysfs unbind, bind nodes, mxcnd_probe and mxcnd_probe_dt can
potentially be called at any time. After the __init functions are cleaned,
mxcnd_probe_dt is no longer available. Calling it anyway causes a crash.

Signed-off-by: Martin Kaiser <martin@kaiser.cx>
---
I hope that my understanding is correct.

In practice, I could not get the kernel to crash, my compiler would
inline mxcnd_probe_dt into mxcnd_probe and ignore the __init.

If I marked mxcnd_probe_dt as noinline, I could trigger a crash as
follows

[root@host ]# echo bb000000.nand > /sys/bus/platform/drivers/mxc_nand/unbind
[root@host ]# echo bb000000.nand > /sys/bus/platform/drivers/mxc_nand/bind
Internal error: Oops - undefined instruction: 0 [#1] ARM
...

drivers/mtd/nand/raw/mxc_nand.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/mtd/nand/raw/mxc_nand.c b/drivers/mtd/nand/raw/mxc_nand.c
index 26cef21..90cfb5e 100644
--- a/drivers/mtd/nand/raw/mxc_nand.c
+++ b/drivers/mtd/nand/raw/mxc_nand.c
@@ -1686,7 +1686,7 @@ static const struct of_device_id mxcnd_dt_ids[] = {
};
MODULE_DEVICE_TABLE(of, mxcnd_dt_ids);

-static int __init mxcnd_probe_dt(struct mxc_nand_host *host)
+static int mxcnd_probe_dt(struct mxc_nand_host *host)
{
struct device_node *np = host->dev->of_node;
const struct of_device_id *of_id =
@@ -1700,7 +1700,7 @@ static int __init mxcnd_probe_dt(struct mxc_nand_host *host)
return 0;
}
#else
-static int __init mxcnd_probe_dt(struct mxc_nand_host *host)
+static int mxcnd_probe_dt(struct mxc_nand_host *host)
{
return 1;
}
--
2.1.4
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