Messages in this thread | | | From | Aisheng Dong <> | Subject | RE: [PATCH] i2c: busses: Fix a reference count leak. | Date | Mon, 15 Jun 2020 06:31:28 +0000 |
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> From: Andy Duan <fugang.duan@nxp.com> > Sent: Monday, June 15, 2020 10:49 AM > > From: wu000273@umn.edu <wu000273@umn.edu> Sent: Sunday, June 14, > 2020 6:12 AM > > From: Qiushi Wu <wu000273@umn.edu> > > > > pm_runtime_get_sync() increments the runtime PM usage counter even > > when it returns an error code. Thus call pm_runtime_put_noidle() if > > pm_runtime_get_sync() fails. > > > > Fixes: 13d6eb20fc79 ("i2c: imx-lpi2c: add runtime pm support") > > Signed-off-by: Qiushi Wu <wu000273@umn.edu> > > Again, which case can trigger the issue ?
It's just error handling improvement because pm_runtime_get_sync() will increase the reference count even it's failed.
I wonder if such de-reference can be better handled by pm runtime core code. Copy pm guys to comment.
Regards Aisheng
> > --- > > drivers/i2c/busses/i2c-imx-lpi2c.c | 4 +++- > > 1 file changed, 3 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/i2c/busses/i2c-imx-lpi2c.c > > b/drivers/i2c/busses/i2c-imx-lpi2c.c > > index 9db6ccded5e9..85b9c1fc7681 100644 > > --- a/drivers/i2c/busses/i2c-imx-lpi2c.c > > +++ b/drivers/i2c/busses/i2c-imx-lpi2c.c > > @@ -260,8 +260,10 @@ static int lpi2c_imx_master_enable(struct > > lpi2c_imx_struct *lpi2c_imx) > > int ret; > > > > ret = pm_runtime_get_sync(lpi2c_imx->adapter.dev.parent); > > - if (ret < 0) > > + if (ret < 0) { > > + pm_runtime_put_noidle(lpi2c_imx->adapter.dev.parent); > > return ret; > > + } > > > > temp = MCR_RST; > > writel(temp, lpi2c_imx->base + LPI2C_MCR); > > -- > > 2.17.1
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