From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=170.10.133.124 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792959563; b=kmW2Sz2lcTrT4faESCs3gv35Wmn4frjkuheBakN8llGqoIQzkQBmsDJe71qvVbpRgElz 9C9F/rvm69n+q7zccW+L5G633m6k1ggULprbcX4DXHvKn6YNL8UUM9aCBUlN09S2m6+KD YMhIivv2Tvueha/bItxvriEqpA9RV57zT/LaEI2pOWBtGsG83uNaSQaewbcFPcEyQ1ovU FJvDNgmCZKFd7j67gGmUxLXGpD80KpMC55byxseVydRWD4yTiS5SyOiXWwpSLsgLeNLqD lCADWRMqZRkKyXx2QKKYB3kB7kYPHJDJJF3Cf42Y8sR6JIgsyZ8e/f+5rsp83R2Hp/w== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792959563; h=DMARC-Filter:DKIM-Signature:Received:X-MC-Unique: X-Mimecast-MFC-AGG-ID:Received:DKIM-Signature:X-Google-DKIM-Signature: X-Forwarded-Encrypted:X-Gm-Message-State:X-Gm-Gg:X-Received: X-Received:Received:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:Content-Transfer-Encoding; bh=ZVwblgn8BYaO2Yir+1yQyjgwaD83vNJgvPl88UMx6rY=; b=3xI0qaJtx387cFSO+gfzI50p7uim7B5CDNFnR9U3PFQwVksTYbLj3JphVX6NC9qR6Asm gnOdIFayE4l0Xi7LLH3q2ap7pySRoJVdktFo74zB9r9Jz2X0j7wvTALlYX60mx8Q18Gw4 X4wLwUkEyipSjuk3aH5iYmIgsjHUacWg6b4lKr21t1AsYRPzIdwAMckV+hsU0oMDWUbtb 8WkS6aS26lRPduhQhS8K28ojfvp7sO6q3KPxcK+vEC63bkV/65wAboRKvDMyO+ncETjgb CzadboccSEdJXwINTKMhNrKYLIfcgZ4DIKGCt+CUOMVBEqKKLTA5yqzdMD8IAnvWHrw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=SJd77E3n; dkim=pass header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=google header.b=jlwOd8Xn; arc=none smtp.remote-ip=170.10.133.124 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D129E606A328 for ; Sun, 25 Oct 2026 20:19:22 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org D129E606A328 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=SJd77E3n; dkim=pass (2048-bit key, unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=google header.b=jlwOd8Xn DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1792959562; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ZVwblgn8BYaO2Yir+1yQyjgwaD83vNJgvPl88UMx6rY=; b=SJd77E3n7NngTgRCIXfrgyW97B/uaLwthf782qZ+ndmoVJ1ux2gHdV/cuP+VmBK86Jw0JC BB/17CHqALBPJ+xznWjDAREXqagD+sJQFf9aftJy8UZX3VAp1eyXudZTYEZTVXllHkWEUw jPFjIjNGojdvAIUze93quUIQD//8O74= Received: from mail-dy1-f198.google.com (mail-dy1-f198.google.com [74.125.82.198]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-326-xraVU1xJMRy8aZ37ItPhQQ-1; Sun, 25 Oct 2026 16:19:20 -0400 X-MC-Unique: xraVU1xJMRy8aZ37ItPhQQ-1 X-Mimecast-MFC-AGG-ID: xraVU1xJMRy8aZ37ItPhQQ_1792959559 Received: by mail-dy1-f198.google.com with SMTP id 5a478bee46e88-36637676140so4075550eec.0 for ; Sun, 25 Oct 2026 13:19:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=google; t=1792959559; x=1793564359; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to:content-type; bh=ZVwblgn8BYaO2Yir+1yQyjgwaD83vNJgvPl88UMx6rY=; b=jlwOd8XnuqKh2GG30zzpHkq+EuKbi/rJtT/yRKaQRrxdUHLwev75bLz6lUhjUnLOE5 aeIM0rmZ4UTsCXlfC7bdBnp1IRGILMEQ3K17QTyM+Bg28clk7atVBphLNT557kpS8qfC fwXDUspvymtdmEOKMwfLkE4OKQ/99XfMLNxkkWdSdjGmks2EtO2AMHQ9sIXBCz143+9N 5vnPjUg0+8+wrvzIypqx3B+70HvZTl6AUiCHvvDenwJxqPnARQHqbVWJSwTMFq/pQsMG bylnojweWal+Xw67HjQpOheMesAfHoIew8Ze572dPOWoY3D4ZFNoZTFiDElPXffVbu1f e06Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1792959559; x=1793564359; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to:content-type; bh=ZVwblgn8BYaO2Yir+1yQyjgwaD83vNJgvPl88UMx6rY=; b=ysD1CoRNMOxGvts4rfdK6PkaPpDsX4eN8Z5DrTQ05L4rD4CDnM6FFNt0/4LMe8QGOg SEf9o3rr4wenQxRfri1ySMAhM/6jCA42ttCoNpQdaN1v+uzLgJnv3DXV1e1AQCMeWtnM vVs4Ks1EoGEvuG+zLAlYBd6HXxpCTzkQwu1px4CIPkJiMRYMSqOtu6RZdJdXVcb2hX+5 ao5Tv9DzmhMK9xQrgqJPt4E/AnL5pzhxgOb9K9m0DPnk2acO2PzViHyWeraaeMqH9HL/ LvGvYJYdthCT+hTmHI17mN/0nId82YNwCHCYtd2AFySS+zbz0makfgsXm7TxkJCDvQGP EiEQ== X-Forwarded-Encrypted: i=1; AKwUvBz1RVrlOWwG87bebr5KJuFq3H7EILqhEv2EFKtoKafpi99gpe3HYXVkvNQRtWzBjjcQazqMFfQFVHGGRUIDujY=@vger.kernel.org X-Gm-Message-State: AFq9FYLDR5+dMc9tSeambhdkA3eMWVvnl96UHtx+2E/w/rKU6Uk+rprn m1WQC1WzmV50iJKTH7lVYrphRMdU8WMj6RzEs56PrHKQbmwntj7tIkrIIc1mCFukr4OMedry5aq Gnw7TAJ95q/FV7Xx6K/yxbqu1DbLb2JJioU7Y9XJvdNCaqDNyDDazC4hRVpBzr7epZwLgbA== X-Gm-Gg: AYBFou3nzP4MT4b3AUzTUY29dZ4nnkwOmLtdDPSQMjA4cBUW+msEBEh38KX7oAroRBl QXKsU9s6GYemzZ17jXpV7TKnL/Jz7X0n6SlNSntM31P/CsJXDjVfqRUX+L73YZlaciqF8/qDoi9 DKM9WAL2MXIXJzbv200CHhqOlSSNC4lxNSb7RhzKZBLdE1QbWiE8U6EVJxom/9EKSfMDsSQtGMP vYLXAlnB1SgubitAUysN3pghLYQf+HJLOocWpKgl8gDbVf03uFZR7fOGZJdna+Nl5a7jBcEGQIB 8dxXXqcGc2hs8uCl1UNXRCONS3amIcNi+3weTLWwmmJzhR7L1Gw7gk3GEbVpy56JT9TuW03XPzK +VBhB1xu+L0sHBv24Nq7ocZGLt4BJIVq7LRSrH9KM X-Received: by 2002:a05:7022:b057:20b0:19a:ace1:793b with SMTP id a92af1059eb24-19aace17b02mr6777430c88.18.1792959559182; Sun, 25 Oct 2026 13:19:19 -0700 (PDT) X-Received: by 2002:a05:7022:b057:20b0:19a:ace1:793b with SMTP id a92af1059eb24-19aace17b02mr6777387c88.18.1792959558551; Sun, 25 Oct 2026 13:19:18 -0700 (PDT) Received: from fedora.armenon-thinkpadp16vgen1.bengluru.csb ([49.47.195.13]) by smtp.gmail.com with ESMTPSA id a92af1059eb24-19894d59f90sm17656169c88.3.2026.10.25.13.19.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 25 Oct 2026 13:19:18 -0700 (PDT) From: Arun Menon To: linux-kernel@vger.kernel.org Cc: Jarkko Sakkinen , linux-integrity@vger.kernel.org, Peter Huewe , Jason Gunthorpe , Arun Menon Subject: [PATCH v4 4/6] tpm: tis_i2c: Use local 4KB buffer to limit memory usage Date: Mon, 26 Oct 2026 01:48:56 +0530 Message-ID: <20261025201859.221991-5-armenon@redhat.com> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20261025201859.221991-1-armenon@redhat.com> References: <20261025201859.221991-1-armenon@redhat.com> X-Mailing-List: linux-integrity@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Arun Menon The global increase of TPM_BUFSIZE to 8KB is necessary to support Post-Quantum Cryptography (PQC) payloads. However, applying this increase to the tpm_tis_i2c driver is unnecessary and wasteful due to physical transport limitations as pointed out in [1] This commit introduces a local buffer limit that is used in the i2c driver. [1] https://sashiko.dev/#/patchset/20260324071803.324774-1-armenon%40redhat.com?patch=8319 Signed-off-by: Arun Menon Reviewed-by: Jarkko Sakkinen --- drivers/char/tpm/tpm_tis_i2c.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/char/tpm/tpm_tis_i2c.c b/drivers/char/tpm/tpm_tis_i2c.c index cde0b093ed58..4667eef15ff1 100644 --- a/drivers/char/tpm/tpm_tis_i2c.c +++ b/drivers/char/tpm/tpm_tis_i2c.c @@ -55,6 +55,8 @@ #define TPM_INTF_CAPABILITY_ZERO 0x0FFFF000 #define TPM_I2C_INTERFACE_CAPABILITY_ZERO 0x80000000 +#define TPM_I2C_BUFSIZE 4096 + struct tpm_tis_i2c_phy { struct tpm_tis_data priv; struct i2c_client *i2c_client; @@ -233,7 +235,7 @@ static int tpm_tis_i2c_write_bytes(struct tpm_tis_data *data, u32 addr, u16 len, int ret; u16 wrote = 0; - if (len > TPM_BUFSIZE - 1) + if (len > TPM_I2C_BUFSIZE - 1) return -EIO; phy->io_buf[0] = reg; @@ -341,7 +343,7 @@ static int tpm_tis_i2c_probe(struct i2c_client *dev) if (!phy) return -ENOMEM; - phy->io_buf = devm_kzalloc(&dev->dev, TPM_BUFSIZE, GFP_KERNEL); + phy->io_buf = devm_kzalloc(&dev->dev, TPM_I2C_BUFSIZE, GFP_KERNEL); if (!phy->io_buf) return -ENOMEM; -- 2.54.0