From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from speedy.danman.eu (speedy.danman.eu [46.227.180.235]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0CA9C1ACE62 for ; Thu, 20 Jun 2024 12:59:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=46.227.180.235 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718888367; cv=none; b=hRv2KlYazlAFkbu1Bzxx3IH2qPzOPSvObEtEWGIu0IqksF017LElvmN+7FSn1/Y1x6irsVcG355tKVfQxbEXB++ntyl4Z/SbqlDcYdpTJgZru8RoQO/NItukIfktugN/kOcCnMSYPiybSGodPCMOtuhlSy0TOpVGYAK97pajdz4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718888367; c=relaxed/simple; bh=KMwWlT6HRkERlJyX/6IpQ36bBlEwEeBQvljwGk0egQU=; h=MIME-Version:Date:From:To:Cc:Subject:In-Reply-To:References: Message-ID:Content-Type; b=aHJh5fEPIYtuxWpd5+eRp+glsD+691Z9ofn2nz4y5qbAOLcJUe/YHn7uYJdpjrnlbXA0mr3+6EkQxqchuye17l12PXP9gWu8yWqc+5YEoJdjc/5t5uIwzEx/Z012VeWmmDmzL0OHHwffuzKC+e/xdVEt7l6PwdzRfRArDSPz6sM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=danman.eu; spf=pass smtp.mailfrom=danman.eu; arc=none smtp.client-ip=46.227.180.235 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=danman.eu Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=danman.eu Received: from mail.danman.eu (localhost [IPv6:::1]) by speedy.danman.eu (Postfix) with ESMTPA id 88A9F24029C; Thu, 20 Jun 2024 14:59:15 +0200 (CEST) Precedence: bulk X-Mailing-List: linux-mmc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Date: Thu, 20 Jun 2024 14:59:15 +0200 From: Daniel Kucera To: Ulf Hansson Cc: linux-mmc@vger.kernel.org Subject: Re: [PATCH v4] mmc: core: allow detection of locked cards In-Reply-To: References: <20240606131222.1131880-1-linux-mmc@danman.eu> User-Agent: Roundcube Webmail/1.5.0 Message-ID: X-Sender: linux-mmc@danman.eu Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit On 2024-06-20 14:38, Ulf Hansson wrote: > On Thu, 6 Jun 2024 at 15:12, wrote: >> >> From: Daniel Kucera >> >> Locked SD card will not reply to SEND_SCR or SD_STATUS commands >> so it was failing to initialize previously. When skipped, >> the card will get initialized and CMD42 can be sent using >> ioctl to unlock the card or remove password protection. >> For eMMC, this is not necessary because all initialization >> commands are allowed in locked state. >> Until unlocked, all read/write calls will timeout. > > Skipping the commands above, only means the card gets partially > initialized. Correct, but it's an improvement in comparison to current state. > Leaving a card in that state seems fragile. Fragile in what sense? Nothing can happen to the card as it is locked. > What will > happen to upper block layers and filesystems when trying to access it? Everything will simply time-out. > > Several years ago Al Cooper made an attempt [1] to manage the > unlocking of the card during initialization, by finding the password > through the "keys" subsystem. The series didn't really make it to the > upstream kernel, but overall the approach seemed to make sense to me. > It should allow us to complete the initialization of the card inside > the kernel and prevent unnecessary complexity for userspace to manage. Yes, he did a great work but obviously no-one got too excited to review/merge his work. His solution was complex. Mine targets the smallest change possible to make it work at least. I wanted to avoid a solution that would be hard to test, review and maintain. Especially when there is only a small interest in the feature. > Perhaps you can have a closer look at that series and see if it's > possible to update it? I don't think I have the skills to revive his work. > > Kind regards > Uffe BR Daniel > > [1] > https://lore.kernel.org/linux-mmc/1433526147-25941-1-git-send-email-alcooperx@gmail.com/ > >> >> Signed-off-by: Daniel Kucera >> --- >> drivers/mmc/core/sd.c | 13 ++++++++++++- >> 1 file changed, 12 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c >> index 1c8148cdd..ae821df7d 100644 >> --- a/drivers/mmc/core/sd.c >> +++ b/drivers/mmc/core/sd.c >> @@ -928,8 +928,19 @@ int mmc_sd_setup_card(struct mmc_host *host, >> struct mmc_card *card, >> bool reinit) >> { >> int err; >> + u32 card_status; >> >> - if (!reinit) { >> + err = mmc_send_status(card, &card_status); >> + if (err){ >> + pr_err("%s: unable to get card status\n", >> mmc_hostname(host)); >> + return err; >> + } >> + >> + if (card_status & R1_CARD_IS_LOCKED){ >> + pr_warn("%s: card is locked\n", mmc_hostname(host)); >> + } >> + >> + if (!reinit && !(card_status & R1_CARD_IS_LOCKED)) { >> /* >> * Fetch SCR from card. >> */ >> -- >> 2.34.1 >>