| Message ID | 20210112141754.76539-1-fengnanchang@gmail.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | mmc: limit the number of retries when analyse tuples failed | expand |
On Tue, 12 Jan 2021 at 15:18, Fengnan Chang <fengnanchang@gmail.com> wrote: > > when analyse tuples failed, may enter an endless loop，so limit the number of retries. > > Signed-off-by: Fengnan Chang <fengnanchang@gmail.com> > --- > drivers/mmc/core/sdio_cis.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/mmc/core/sdio_cis.c b/drivers/mmc/core/sdio_cis.c > index dcb3dee59fa5..a3f0c3cc0c2c 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; > + int tries = 100; > From a general point of view I agree, we should set a limit to avoid looping forever. Although, I am wondering why exactly is 100 a good value for retries? Did you encounter this problem and tried to limit the loop to 100 to fix the problem - or is the fix done based on pure code analysis? An option to limit the loop with retries is to bail out when a timer elapses. Perhaps that is better suited for this case or what do you think? > ret = mmc_io_rw_direct(card, 0, 0, ptr++, 0, &tpl_code); > if (ret) > @@ -318,6 +319,9 @@ static int sdio_read_cis(struct mmc_card *card, struct sdio_func *func) > prev = &this->next; > > if (ret == -ENOENT) { > + tries--; > + if (!tries) > + break; > /* warn about unknown tuples */ > pr_warn_ratelimited("%s: queuing unknown" > " CIS tuple 0x%02x (%u bytes)\n", > -- > 2.25.1 > Kind regards Uffe
diff --git a/drivers/mmc/core/sdio_cis.c b/drivers/mmc/core/sdio_cis.c index dcb3dee59fa5..a3f0c3cc0c2c 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; + int tries = 100; ret = mmc_io_rw_direct(card, 0, 0, ptr++, 0, &tpl_code); if (ret) @@ -318,6 +319,9 @@ static int sdio_read_cis(struct mmc_card *card, struct sdio_func *func) prev = &this->next; if (ret == -ENOENT) { + tries--; + if (!tries) + break; /* warn about unknown tuples */ pr_warn_ratelimited("%s: queuing unknown" " CIS tuple 0x%02x (%u bytes)\n",
when analyse tuples failed, may enter an endless loop，so limit the number of retries. Signed-off-by: Fengnan Chang <fengnanchang@gmail.com> --- drivers/mmc/core/sdio_cis.c | 4 ++++ 1 file changed, 4 insertions(+)