diff mbox series

[v2] mmc: limit the time of retries when analyse tuples failed

Message ID 20210120144550.697303-1-fengnanchang@gmail.com
State New
Headers show
Series [v2] mmc: limit the time of retries when analyse tuples failed | expand

Commit Message

fengnan chang Jan. 20, 2021, 2:45 p.m. UTC
when analyse tuples failed, may enter an endless loop,so limit the time of retries.

Signed-off-by: Fengnan Chang <fengnanchang@gmail.com>
---
 drivers/mmc/core/sdio_cis.c | 3 +++
 1 file changed, 3 insertions(+)

--
2.25.1

Comments

Ulf Hansson Jan. 20, 2021, 3:28 p.m. UTC | #1
On Wed, 20 Jan 2021 at 15:47, Fengnan Chang <fengnanchang@gmail.com> wrote:
>
> when analyse tuples failed, may enter an endless loop,so limit the time of retries.

Since this is fixing a real bug for you, it looks like we should tag
this for stable kernels as well, right?

>
> Signed-off-by: Fengnan Chang <fengnanchang@gmail.com>
> ---
>  drivers/mmc/core/sdio_cis.c | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/drivers/mmc/core/sdio_cis.c b/drivers/mmc/core/sdio_cis.c
> index dcb3dee59fa5..47423a6d13fb 100644
> --- a/drivers/mmc/core/sdio_cis.c
> +++ b/drivers/mmc/core/sdio_cis.c
> @@ -266,6 +266,7 @@ static int sdio_read_cis(struct mmc_card *card, struct sdio_func *func)
>
>         do {
>                 unsigned char tpl_code, tpl_link;
> +               u64 timeout = get_jiffies_64() + 10 * HZ;

To be consistent with how we do time based polling (see
__mmc_poll_for_busy() in mmc_ops.c for example) I would prefer if you
use a define for the timeout, rather than a magic value as here.

#define SDIO_READ_CIS_TIMEOUT_MS  (10 * 1000) /* 10s */

Additionally, regular jiffies should be sufficient I think. Thus I
prefer if you could specify the timeout along the lines like the
below:
timeout = jiffies + msecs_to_jiffies(SDIO_READ_CIS_TIMEOUT_MS);

>
>                 ret = mmc_io_rw_direct(card, 0, 0, ptr++, 0, &tpl_code);
>                 if (ret)
> @@ -318,6 +319,8 @@ static int sdio_read_cis(struct mmc_card *card, struct sdio_func *func)
>                         prev = &this->next;
>
>                         if (ret == -ENOENT) {
> +                               if (time_after64(get_jiffies_64(), timeout))
> +                                       break;
>                                 /* warn about unknown tuples */
>                                 pr_warn_ratelimited("%s: queuing unknown"
>                                        " CIS tuple 0x%02x (%u bytes)\n",
> --
> 2.25.1
>

Other than that, this looks okay to me.

Kind regards
Uffe
fengnan chang Jan. 23, 2021, 3:08 a.m. UTC | #2
yeah, I think it should tag this for stable kernels as well.
I will send a new version later.

Ulf Hansson <ulf.hansson@linaro.org> 于2021年1月20日周三 下午11:29写道:
>

> On Wed, 20 Jan 2021 at 15:47, Fengnan Chang <fengnanchang@gmail.com> wrote:

> >

> > when analyse tuples failed, may enter an endless loop,so limit the time of retries.

>

> Since this is fixing a real bug for you, it looks like we should tag

> this for stable kernels as well, right?

>

> >

> > Signed-off-by: Fengnan Chang <fengnanchang@gmail.com>

> > ---

> >  drivers/mmc/core/sdio_cis.c | 3 +++

> >  1 file changed, 3 insertions(+)

> >

> > diff --git a/drivers/mmc/core/sdio_cis.c b/drivers/mmc/core/sdio_cis.c

> > index dcb3dee59fa5..47423a6d13fb 100644

> > --- a/drivers/mmc/core/sdio_cis.c

> > +++ b/drivers/mmc/core/sdio_cis.c

> > @@ -266,6 +266,7 @@ static int sdio_read_cis(struct mmc_card *card, struct sdio_func *func)

> >

> >         do {

> >                 unsigned char tpl_code, tpl_link;

> > +               u64 timeout = get_jiffies_64() + 10 * HZ;

>

> To be consistent with how we do time based polling (see

> __mmc_poll_for_busy() in mmc_ops.c for example) I would prefer if you

> use a define for the timeout, rather than a magic value as here.

>

> #define SDIO_READ_CIS_TIMEOUT_MS  (10 * 1000) /* 10s */

>

> Additionally, regular jiffies should be sufficient I think. Thus I

> prefer if you could specify the timeout along the lines like the

> below:

> timeout = jiffies + msecs_to_jiffies(SDIO_READ_CIS_TIMEOUT_MS);

>

> >

> >                 ret = mmc_io_rw_direct(card, 0, 0, ptr++, 0, &tpl_code);

> >                 if (ret)

> > @@ -318,6 +319,8 @@ static int sdio_read_cis(struct mmc_card *card, struct sdio_func *func)

> >                         prev = &this->next;

> >

> >                         if (ret == -ENOENT) {

> > +                               if (time_after64(get_jiffies_64(), timeout))

> > +                                       break;

> >                                 /* warn about unknown tuples */

> >                                 pr_warn_ratelimited("%s: queuing unknown"

> >                                        " CIS tuple 0x%02x (%u bytes)\n",

> > --

> > 2.25.1

> >

>

> Other than that, this looks okay to me.

>

> Kind regards

> Uffe
diff mbox series

Patch

diff --git a/drivers/mmc/core/sdio_cis.c b/drivers/mmc/core/sdio_cis.c
index dcb3dee59fa5..47423a6d13fb 100644
--- a/drivers/mmc/core/sdio_cis.c
+++ b/drivers/mmc/core/sdio_cis.c
@@ -266,6 +266,7 @@  static int sdio_read_cis(struct mmc_card *card, struct sdio_func *func)

 	do {
 		unsigned char tpl_code, tpl_link;
+		u64 timeout = get_jiffies_64() + 10 * HZ;

 		ret = mmc_io_rw_direct(card, 0, 0, ptr++, 0, &tpl_code);
 		if (ret)
@@ -318,6 +319,8 @@  static int sdio_read_cis(struct mmc_card *card, struct sdio_func *func)
 			prev = &this->next;

 			if (ret == -ENOENT) {
+				if (time_after64(get_jiffies_64(), timeout))
+					break;
 				/* warn about unknown tuples */
 				pr_warn_ratelimited("%s: queuing unknown"
 				       " CIS tuple 0x%02x (%u bytes)\n",