From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 08662C388F2 for ; Tue, 3 Nov 2020 04:16:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A687D22275 for ; Tue, 3 Nov 2020 04:16:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604377012; bh=OZ57ilRRKIChFrCf8LKFDpE1JRRZmQtCgsyN5ajkD1Q=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=FHezHz8svVFh9P1S8PK3Wev8fLjzTf4RsgW6RLhPxqdcBZby3IOKeK6IoE+iTlEAo dNej3DR9zZ8/j1npQrqUNfY7bYCK7xD8+vpslyRlwK73/iTW4NAbXwe3A166YbPMSq 7n8j5wj3MpKzUGf8H011zvsOrfuUzg/MnA/LigKg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725968AbgKCEQw (ORCPT ); Mon, 2 Nov 2020 23:16:52 -0500 Received: from mail.kernel.org ([198.145.29.99]:39712 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725940AbgKCEQv (ORCPT ); Mon, 2 Nov 2020 23:16:51 -0500 Received: from kernel.org (83-245-197-237.elisa-laajakaista.fi [83.245.197.237]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A12A620756; Tue, 3 Nov 2020 04:16:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604377009; bh=OZ57ilRRKIChFrCf8LKFDpE1JRRZmQtCgsyN5ajkD1Q=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=JEtq0Clv/SehFsiJJK2cieB0KD3MThXRJEM6/p0m88RTNY6Rz3VeCKzEoQsGaZnS9 a3VXMAhFKHs/45q5xXP9EIcQPKhLHDbX9HHcC9XAzosz0mVqL6D6kjeULhPqFkPssr jePT0NNp/5GFw2lxtTs3/hn15PY5ZvoGl9DzH/vM= Date: Tue, 3 Nov 2020 06:16:44 +0200 From: Jarkko Sakkinen To: Jerry Snitselaar Cc: James Bottomley , linux-integrity@vger.kernel.org, Jason Gunthorpe , Jarkko Sakkinen , Peter Huewe Subject: Re: [PATCH v2 3/5] tpm_tis: Fix interrupts for TIS TPMs without legacy cycles Message-ID: <20201103041644.GA56284@kernel.org> References: <20201001180925.13808-1-James.Bottomley@HansenPartnership.com> <20201001180925.13808-4-James.Bottomley@HansenPartnership.com> <87zh4h7nz1.fsf@redhat.com> <20201024121553.GB32960@kernel.org> <20201030121838.GC522355@kernel.org> <87v9erbsvk.fsf@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87v9erbsvk.fsf@redhat.com> Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org On Fri, Oct 30, 2020 at 09:06:39AM -0700, Jerry Snitselaar wrote: > > Jarkko Sakkinen @ 2020-10-30 05:18 MST: > > > On Sat, Oct 24, 2020 at 03:15:53PM +0300, Jarkko Sakkinen wrote: > >> On Mon, Oct 19, 2020 at 05:14:26PM -0700, Jerry Snitselaar wrote: > >> > > >> > James Bottomley @ 2020-10-01 11:09 MST: > >> > > >> > > If a TIS TPM doesn't have legacy cycles, any write to the interrupt > >> > > registers is ignored unless a locality is active. This means even to > >> > > set up the interrupt vectors a locality must first be activated. Fix > >> > > this by activating the 0 locality in the interrupt probe setup. > >> > > > >> > > Since the TPM_EOI signalling also requires an active locality, the > >> > > interrupt routine cannot end an interrupt if the locality is released. > >> > > This can lead to a situation where the TPM goes command ready after > >> > > locality release and since the interrupt cannot be ended it refires > >> > > continuously. Fix this by disabling all interrupts except locality > >> > > change when a locality is released (this only fires when a locality > >> > > becomes active, meaning the TPM_EOI should work). > >> > > > >> > > Finally, since we now disable all status based interrupts in the > >> > > locality release, they must be re-enabled before waiting to check the > >> > > condition, so add interrupt enabling to the status wait. > >> > > > >> > > Signed-off-by: James Bottomley > >> > > > >> > > --- > >> > > > >> > > v2: renamed functions > >> > > --- > >> > > drivers/char/tpm/tpm_tis_core.c | 125 ++++++++++++++++++++++++++------ > >> > > 1 file changed, 101 insertions(+), 24 deletions(-) > >> > > > >> > > diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c > >> > > index 431919d5f48a..0c07da8cd680 100644 > >> > > --- a/drivers/char/tpm/tpm_tis_core.c > >> > > +++ b/drivers/char/tpm/tpm_tis_core.c > >> > > @@ -29,6 +29,46 @@ > >> > > > >> > > static void tpm_tis_clkrun_enable(struct tpm_chip *chip, bool value); > >> > > > >> > > +static void tpm_tis_enable_interrupt(struct tpm_chip *chip, u8 mask) > >> > > +{ > >> > > + struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev); > >> > > + u32 intmask; > >> > > + > >> > > + /* Take control of the TPM's interrupt hardware and shut it off */ > >> > > >> > s/shut it off/turn it on/ ? > >> > > >> > > + tpm_tis_read32(priv, TPM_INT_ENABLE(priv->locality), &intmask); > >> > > + > >> > > + intmask |= mask | TPM_GLOBAL_INT_ENABLE; > >> > > + > >> > > + tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality), intmask); > >> > > +} > >> > > + > >> > > +static void tpm_tis_disable_interrupt(struct tpm_chip *chip, u8 mask) > >> > > +{ > >> > > + struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev); > >> > > + u32 intmask; > >> > > + > >> > > + /* Take control of the TPM's interrupt hardware and shut it off */ > >> > > + tpm_tis_read32(priv, TPM_INT_ENABLE(priv->locality), &intmask); > >> > > + > >> > > + intmask &= ~mask; > >> > > + > >> > > + tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality), intmask); > >> > > +} > >> > > + > >> > > +static void tpm_tis_enable_stat_interrupts(struct tpm_chip *chip, u8 stat) > >> > > +{ > >> > > + u32 mask = 0; > >> > > + > >> > > + if (stat & TPM_STS_COMMAND_READY) > >> > > + mask |= TPM_INTF_CMD_READY_INT; > >> > > + if (stat & TPM_STS_VALID) > >> > > + mask |= TPM_INTF_STS_VALID_INT; > >> > > + if (stat & TPM_STS_DATA_AVAIL) > >> > > + mask |= TPM_INTF_DATA_AVAIL_INT; > >> > > + > >> > > + tpm_tis_enable_interrupt(chip, mask); > >> > > +} > >> > > + > >> > > static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask, > >> > > bool check_cancel, bool *canceled) > >> > > { > >> > > @@ -65,11 +105,14 @@ static int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, > >> > > timeout = stop - jiffies; > >> > > if ((long)timeout <= 0) > >> > > return -ETIME; > >> > > + tpm_tis_enable_stat_interrupts(chip, mask); > >> > > rc = wait_event_interruptible_timeout(*queue, > >> > > wait_for_tpm_stat_cond(chip, mask, check_cancel, > >> > > &canceled), > >> > > timeout); > >> > > if (rc > 0) { > >> > > + if (rc == 1) > >> > > + dev_err(&chip->dev, "Lost Interrupt waiting for TPM stat\n"); > >> > > if (canceled) > >> > > return -ECANCELED; > >> > > return 0; > >> > > @@ -138,6 +181,28 @@ static bool check_locality(struct tpm_chip *chip, int l) > >> > > static int release_locality(struct tpm_chip *chip, int l) > >> > > { > >> > > struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev); > >> > > + u32 int_status; > >> > > + int rc; > >> > > + > >> > > + /* > >> > > + * Note that once we relinquish the locality, all writes to > >> > > + * the interrupt registers become ineffective meaning we can't > >> > > + * do a TPM_EOI. This means we must disable every interrupt > >> > > + * except the locality change one to avoid interrupt > >> > > + * storms. > >> > > + */ > >> > > + tpm_tis_disable_interrupt(chip, TPM_INTF_CMD_READY_INT > >> > > + | TPM_INTF_STS_VALID_INT > >> > > + | TPM_INTF_DATA_AVAIL_INT); > >> > > + > >> > > + rc = tpm_tis_read32(priv, TPM_INT_STATUS(priv->locality), &int_status); > >> > > + if (rc < 0) > >> > > + return rc; > >> > > + > >> > > + /* Clear all pending */ > >> > > + rc = tpm_tis_write32(priv, TPM_INT_STATUS(priv->locality), int_status); > >> > > + if (rc < 0) > >> > > + return rc; > >> > > > >> > > tpm_tis_write8(priv, TPM_ACCESS(l), TPM_ACCESS_ACTIVE_LOCALITY); > >> > > > >> > > @@ -164,12 +229,17 @@ static int request_locality(struct tpm_chip *chip, int l) > >> > > timeout = stop - jiffies; > >> > > if ((long)timeout <= 0) > >> > > return -1; > >> > > + > >> > > rc = wait_event_interruptible_timeout(priv->int_queue, > >> > > (check_locality > >> > > (chip, l)), > >> > > timeout); > >> > > - if (rc > 0) > >> > > + if (rc > 1) > >> > > + return l; > >> > > + if (rc == 1) { > >> > > + dev_info(&chip->dev, "Lost Interrupt waiting for locality\n"); > >> > > return l; > >> > > + } > >> > > if (rc == -ERESTARTSYS && freezing(current)) { > >> > > clear_thread_flag(TIF_SIGPENDING); > >> > > goto again; > >> > > @@ -465,6 +535,10 @@ static int tpm_tis_send(struct tpm_chip *chip, u8 *buf, size_t len) > >> > > irq = priv->irq; > >> > > priv->irq = 0; > >> > > chip->flags &= ~TPM_CHIP_FLAG_IRQ; > >> > > + tpm_tis_enable_interrupt(chip, TPM_INTF_CMD_READY_INT > >> > > + | TPM_INTF_LOCALITY_CHANGE_INT > >> > > + | TPM_INTF_DATA_AVAIL_INT > >> > > + | TPM_INTF_STS_VALID_INT); > >> > > rc = tpm_tis_send_main(chip, buf, len); > >> > > priv->irq = irq; > >> > > chip->flags |= TPM_CHIP_FLAG_IRQ; > >> > > @@ -719,7 +793,7 @@ static int tpm_tis_gen_interrupt(struct tpm_chip *chip) > >> > > * irq is seen then leave the chip setup for IRQ operation, otherwise reverse > >> > > * everything and leave in polling mode. Returns 0 on success. > >> > > */ > >> > > -static int tpm_tis_probe_irq_single(struct tpm_chip *chip, u32 intmask, > >> > > +static int tpm_tis_probe_irq_single(struct tpm_chip *chip, > >> > > int flags, int irq) > >> > > { > >> > > struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev); > >> > > @@ -753,9 +827,11 @@ static int tpm_tis_probe_irq_single(struct tpm_chip *chip, u32 intmask, > >> > > if (rc < 0) > >> > > return rc; > >> > > > >> > > - /* Turn on */ > >> > > - rc = tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality), > >> > > - intmask | TPM_GLOBAL_INT_ENABLE); > >> > > + /* > >> > > + * Turn on. The locality change interrupt is the only one > >> > > + * always enabled > >> > > + */ > >> > > + tpm_tis_enable_interrupt(chip, TPM_INTF_LOCALITY_CHANGE_INT); > >> > > if (rc < 0) > >> > > return rc; > >> > > > >> > > @@ -787,7 +863,7 @@ static int tpm_tis_probe_irq_single(struct tpm_chip *chip, u32 intmask, > >> > > * do not have ACPI/etc. We typically expect the interrupt to be declared if > >> > > * present. > >> > > */ > >> > > -static void tpm_tis_probe_irq(struct tpm_chip *chip, u32 intmask) > >> > > +static void tpm_tis_probe_irq(struct tpm_chip *chip) > >> > > { > >> > > struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev); > >> > > u8 original_int_vec; > >> > > @@ -801,11 +877,9 @@ static void tpm_tis_probe_irq(struct tpm_chip *chip, u32 intmask) > >> > > if (!original_int_vec) { > >> > > if (IS_ENABLED(CONFIG_X86)) > >> > > for (i = 3; i <= 15; i++) > >> > > - if (!tpm_tis_probe_irq_single(chip, intmask, 0, > >> > > - i)) > >> > > + if (!tpm_tis_probe_irq_single(chip, 0, i)) > >> > > return; > >> > > - } else if (!tpm_tis_probe_irq_single(chip, intmask, 0, > >> > > - original_int_vec)) > >> > > + } else if (!tpm_tis_probe_irq_single(chip, 0, original_int_vec)) > >> > > return; > >> > > } > >> > > > >> > > @@ -1030,8 +1104,7 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq, > >> > > } > >> > > > >> > > if (irq) { > >> > > - tpm_tis_probe_irq_single(chip, intmask, IRQF_SHARED, > >> > > - irq); > >> > > + tpm_tis_probe_irq_single(chip, IRQF_SHARED, irq); > >> > > if (!(chip->flags & TPM_CHIP_FLAG_IRQ)) { > >> > > dev_err(&chip->dev, FW_BUG > >> > > "TPM interrupt not working, polling instead\n"); > >> > > @@ -1039,7 +1112,7 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq, > >> > > disable_interrupts(chip); > >> > > } > >> > > } else { > >> > > - tpm_tis_probe_irq(chip, intmask); > >> > > + tpm_tis_probe_irq(chip); > >> > > } > >> > > } > >> > > > >> > > @@ -1065,12 +1138,23 @@ EXPORT_SYMBOL_GPL(tpm_tis_core_init); > >> > > static void tpm_tis_reenable_interrupts(struct tpm_chip *chip) > >> > > { > >> > > struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev); > >> > > - u32 intmask; > >> > > int rc; > >> > > > >> > > if (chip->ops->clk_enable != NULL) > >> > > chip->ops->clk_enable(chip, true); > >> > > > >> > > + /* > >> > > + * must have the locality before we can enable interrupts, so > >> > > + * poll for the locality being ready > >> > > + */ > >> > > + chip->flags &= ~TPM_CHIP_FLAG_IRQ; > >> > > + if (request_locality(chip, 0) != 0) { > >> > > + dev_err(&chip->dev, "Failed to enable interrupts after suspend\n"); > >> > > + goto out; > >> > > + } > >> > > + chip->flags |= TPM_CHIP_FLAG_IRQ; > >> > > + > >> > > + > >> > > /* reenable interrupts that device may have lost or > >> > > * BIOS/firmware may have disabled > >> > > */ > >> > > @@ -1078,17 +1162,10 @@ static void tpm_tis_reenable_interrupts(struct tpm_chip *chip) > >> > > if (rc < 0) > >> > > goto out; > >> > > > >> > > - rc = tpm_tis_read32(priv, TPM_INT_ENABLE(priv->locality), &intmask); > >> > > - if (rc < 0) > >> > > - goto out; > >> > > - > >> > > - intmask |= TPM_INTF_CMD_READY_INT > >> > > - | TPM_INTF_LOCALITY_CHANGE_INT | TPM_INTF_DATA_AVAIL_INT > >> > > - | TPM_INTF_STS_VALID_INT | TPM_GLOBAL_INT_ENABLE; > >> > > + tpm_tis_enable_interrupt(chip, TPM_INTF_LOCALITY_CHANGE_INT); > >> > > > >> > > - tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality), intmask); > >> > > - > >> > > -out: > >> > > + out: > >> > > + release_locality(chip, 0); > >> > > if (chip->ops->clk_enable != NULL) > >> > > chip->ops->clk_enable(chip, false); > >> > > >> > Other than the question about the comment in tpm_tis_enable_interrupt > >> > > >> > Reviewed-by: Jerry Snitselaar > >> > >> Should this have > >> > >> Fixes: e6aef069b6e9 ("tpm_tis: convert to using locality callbacks") > >> > >> ? > > > > ? > > > > /Jarkko > > Yes, I believe so. OK, let's have it in the next patch set version. /Jarkko