| From | Kamal Mostafa <> | Subject | [PATCH 3.13 020/105] mmc: tmio: prevent endless loop in tmio_mmc_set_clock() | Date | Mon, 27 Oct 2014 11:55:55 -0700 |
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3.13.11.10 -stable review patch. If anyone has any objections, please let me know.
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From: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
commit bb98d9d1d2e791f368295c9c09c9a03fe3ac0e62 upstream.
I spent a couple of days with the driver just hanging due to me forgetting to specify the external crystal frequency, so that clk_get_rate() returned 0 and thus the loop in tmio_mmc_set_clock() never ended. I don't think that's an acceptable behavior, so I suggest that the minimum frequency is checked for 0 in tmio_mmc_host_probe().
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Acked-by: Ian Molton <ian.molton@codethink.co.uk> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- drivers/mmc/host/tmio_mmc_pio.c | 9 +++++++++ 1 file changed, 9 insertions(+)
diff --git a/drivers/mmc/host/tmio_mmc_pio.c b/drivers/mmc/host/tmio_mmc_pio.c index f3b2d8c..51add7f 100644 --- a/drivers/mmc/host/tmio_mmc_pio.c +++ b/drivers/mmc/host/tmio_mmc_pio.c @@ -1042,6 +1042,15 @@ int tmio_mmc_host_probe(struct tmio_mmc_host **host, } /* + * Check the sanity of mmc->f_min to prevent tmio_mmc_set_clock() from + * looping forever... + */ + if (mmc->f_min == 0) { + ret = -EINVAL; + goto host_free; + } + + /* * There are 4 different scenarios for the card detection: * 1) an external gpio irq handles the cd (best for power savings) * 2) internal sdhi irq handles the cd -- 1.9.1
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