From: Ulf Hansson <ulf.hansson@linaro.org>
To: Chris Ball <cjb@laptop.org>
Cc: Sergey Yanovich <ynvich@gmail.com>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Linus Walleij <linus.walleij@linaro.org>,
Jaehoon Chung <jh80.chung@samsung.com>,
Namjae Jeon <linkinjeon@gmail.com>,
linux-kernel@vger.kernel.org, linux-mmc@vger.kernel.org
Subject: Re: [PATCH v2] wait while adding MMC host to ensure root mounts
Date: Wed, 27 Mar 2013 12:13:12 +0100 [thread overview]
Message-ID: <CAPDyKFp27MUOjhydLXf92vN3cua=XcX4oTJnMGfOJPpBhtwM8Q@mail.gmail.com> (raw)
In-Reply-To: <87620jmkoe.fsf@octavius.laptop.org>
On 22 March 2013 18:03, Chris Ball <cjb@laptop.org> wrote:
> Hi Sergey,
>
> On Wed, Mar 13 2013, Sergey Yanovich wrote:
>> MMC hosts are added asynchronously. We need to wait until detect returns to
>> avoid failed root filesystem mounts.
>> ---8<---
>> VFS: Cannot open root device "mmcblk0p1" or unknown-block(0,0): error -6
>> Please append a correct "root=" boot option; here are the available partitions:
>> mmc0: host does not support reading read-only switch. assuming write-enable.
>> 1f00 256 mtdblock0 (driver?)
>> 1f01 256 mtdblock1 (driver?)
>> 1f02 2560 mtdblock2 mmc0: new SDHC card at address b368
>> (driver?)
>> 1f03 29696 mtdblock3 (driver?)
>> 1f04 16384 mtdblock4 mmcblk0: mmc0:b368 USD 3.72 GiB
>> (driver?)
>> mmcblk0: p1
>> b300 3910656 mmcblk0 driver: mmcblk
>> b301 3906560 mmcblk0p1 00000000-01
>> Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)
>> ---8<---
>>
>> Signed-off-by: Sergey Yanovich <ynvich@gmail.com>
>> ---
>> changes for v2:
>> - removed exporting as symbol is in the same file
>>
>> drivers/mmc/core/core.c | 1 +
>> 1 file changed, 1 insertion(+)
>>
>> diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
>> index aaed768..7196888 100644
>> --- a/drivers/mmc/core/core.c
>> +++ b/drivers/mmc/core/core.c
>> @@ -2225,6 +2225,7 @@ void mmc_start_host(struct mmc_host *host)
>> host->rescan_disable = 0;
>> mmc_power_up(host);
>> mmc_detect_change(host, 0);
>> + mmc_flush_scheduled_work();
>> }
>>
>> void mmc_stop_host(struct mmc_host *host)
>
> Thanks, this looks okay to me, I've pushed it to mmc-next for 3.10.
>
> - Chris.
> --
> Chris Ball <cjb@laptop.org> <http://printf.net/>
> One Laptop Per Child
Hi Chris,
I noticed you merged this. I thought the idea was to use the rootwait
or rootdelay?
Moreover, this patch will have bad impact on booting the kernel, since
every host device that has scheduled a detect work from it's probe
function will also wait for it to finish. Even if it is the boot
device of not. If this is needed, I would prefer that a host cap is
used.
Kind regards
Ulf Hansson
next prev parent reply other threads:[~2013-03-27 11:13 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-03-14 1:06 [PATCH] wait while adding MMC host to ensure root mounts Sergey Yanovich
2013-03-14 1:23 ` [PATCH v2] " Sergey Yanovich
2013-03-14 4:08 ` Namjae Jeon
2013-03-14 11:57 ` Sergey Yanovich
2013-03-15 2:51 ` Jaehoon Chung
2013-03-22 17:03 ` Chris Ball
2013-03-27 11:13 ` Ulf Hansson [this message]
2013-03-27 11:57 ` Chris Ball
2013-04-02 13:36 ` Adrian Hunter
2013-04-02 14:24 ` Sergey Yanovich
2013-04-04 6:35 ` Adrian Hunter
2013-04-04 10:59 ` Sergey Yanovich
2013-04-04 11:35 ` Adrian Hunter
2013-04-04 12:32 ` Sergey Yanovich
2013-04-13 10:49 ` Sergey Yanovich
2013-04-13 12:52 ` Chris Ball
[not found] ` <CAPDyKFrF8pmo7mfa_1Vi2n=JBFd1h+VULQ1hJB75=DmNx0erdw@mail.gmail.com>
2013-04-13 12:52 ` Sergey Yanovich
2013-03-27 12:28 ` Сергей Янович
2013-04-02 10:13 ` Ulf Hansson
2013-04-02 10:35 ` Sergey Yanovich
2013-04-02 17:45 ` Ulf Hansson
2013-04-02 18:56 ` Sergey Yanovich
2013-03-14 2:47 ` [PATCH] " Greg Kroah-Hartman
2013-03-14 10:28 ` Sergey Yanovich
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