linux-kernel - Re: [PATCH V6 06/24] mmc: core: Support UHS-II card control and access

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Thu, 5 Jan 2023 23:26:20 +0200
From:   Adrian Hunter <adrian.hunter@...el.com>
To:     Victor Shih <victorshihgli@...il.com>, ulf.hansson@...aro.org
Cc:     linux-mmc@...r.kernel.org, linux-kernel@...r.kernel.org,
        benchuanggli@...il.com, HL.Liu@...esyslogic.com.tw,
        Greg.tu@...esyslogic.com.tw, takahiro.akashi@...aro.org,
        dlunev@...omium.org, Victor Shih <victor.shih@...esyslogic.com.tw>,
        Jason Lai <jason.lai@...esyslogic.com.tw>
Subject: Re: [PATCH V6 06/24] mmc: core: Support UHS-II card control and
 access

On 13/12/22 11:00, Victor Shih wrote:
> Embed UHS-II access/control functionality into the MMC request
> processing flow.
> 
> Signed-off-by: Ulf Hansson <ulf.hansson@...aro.org>
> Signed-off-by: Jason Lai <jason.lai@...esyslogic.com.tw>
> Signed-off-by: Victor Shih <victor.shih@...esyslogic.com.tw>
> ---
>  drivers/mmc/core/block.c   |    6 +-
>  drivers/mmc/core/core.c    |   20 +
>  drivers/mmc/core/mmc_ops.c |   25 +-
>  drivers/mmc/core/mmc_ops.h |    1 +
>  drivers/mmc/core/sd.c      |   11 +-
>  drivers/mmc/core/sd.h      |    3 +
>  drivers/mmc/core/sd_ops.c  |   13 +
>  drivers/mmc/core/sd_ops.h  |    3 +
>  drivers/mmc/core/sd_uhs2.c | 1171 +++++++++++++++++++++++++++++++++++-
>  9 files changed, 1206 insertions(+), 47 deletions(-)
> 

<SNIP>

> diff --git a/drivers/mmc/core/sd_uhs2.c b/drivers/mmc/core/sd_uhs2.c
> index 800957f74632..a79eb08ec540 100644
> --- a/drivers/mmc/core/sd_uhs2.c
> +++ b/drivers/mmc/core/sd_uhs2.c

<SNIP>

> +/*
> + * Mask off any voltages we don't support and select
> + * the lowest voltage
> + */
> +u32 sd_uhs2_select_voltage(struct mmc_host *host, u32 ocr)
> +{
> +	int bit;
> +	int err;
> +
> +	/*
> +	 * Sanity check the voltages that the card claims to
> +	 * support.
> +	 */
> +	if (ocr & 0x7F) {
> +		dev_warn(mmc_dev(host), "card claims to support voltages below defined range\n");
> +		ocr &= ~0x7F;
> +	}
> +
> +	ocr &= host->ocr_avail;
> +	if (!ocr) {
> +		dev_warn(mmc_dev(host), "no support for card's volts\n");
> +		return 0;
> +	}
> +
> +	if (host->caps2 & MMC_CAP2_FULL_PWR_CYCLE) {
> +		bit = ffs(ocr) - 1;
> +		ocr &= 3 << bit;
> +		/* Power cycle */
> +		err = sd_uhs2_power_off(host);
> +		if (err)
> +			return 0;
> +		err = sd_uhs2_reinit(host);

This looks circular:

sd_uhs2_select_voltage
-> sd_uhs2_reinit
   -> sd_uhs2_init_card
      -> sd_uhs2_legacy_init
         -> sd_uhs2_select_voltage

> +		if (err)
> +			return 0;
> +	} else {
> +		bit = fls(ocr) - 1;
> +		ocr &= 3 << bit;
> +		if (bit != host->ios.vdd)
> +			dev_warn(mmc_dev(host), "exceeding card's volts\n");
> +	}
> +
> +	return ocr;
> +}
> +

<SNIP>