From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 C3FE437524F for ; Sat, 28 Feb 2026 18:16:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772302561; cv=none; b=jWgnfm8aLD8GwFNFPyKScX21VRKhs/XAealcN2Nk9DdJiRlZuiPkSsjN6s7KexwzhHs7JRWz1nln9aX33wKTmQB+oDTim9ng+q9wuTYOZw0ozhPpIX8dRtvVH4WSXrhxmrujTGT4TJtnVc5db9qh92FYHgx49Ui2rrkOSizH6wM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772302561; c=relaxed/simple; bh=34Nx6kIswZJsO3rC8rGYfiI2n7jVxCa4GtrJ90uta60=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=AR0PNQrZI9tiFltN4zgWF/Hns6si7akkcBjKbhE0951Uq/MsEo5xyIIlssR05KsAw7wh3EGke9baoFg2VEARW/7eoSgIXozXj8Dp+IUd7quCG1dsfwzKV5Y9zHD7EFONFDz+XWpPluydjBXwdOFabyuPtwf1sPd2MfhY3zVv+WY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=CoMzty8M; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="CoMzty8M" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0BD30C19423; Sat, 28 Feb 2026 18:16:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772302561; bh=34Nx6kIswZJsO3rC8rGYfiI2n7jVxCa4GtrJ90uta60=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CoMzty8Mn6YeZKQ0faOPneS1+erHXjKnT9l4Tr+pGvDeZNT/vaNHcZxF+DOLKQK1q Jmrd7F9v7NjZTu9CLeescOi7CtUlzZrPuDGMx9Yjfd8oO01K8wtR5orsRzn1ZmyAvS 86myamRmDp27BMfJeV4oU8H5aUqKMW83hW9iZetPy9Wa+9h8aYeweTJyWi96k3v6ik knkrs0Dt5xT3/TFTeXZHkslHf6dkS7Za1dFVXyaiNaHJ57K1K0CVVrdFzHPvMhFmyv Pnyg4UpfomlZG5WI6oi01n40fwZa+eI/Um3kSrQDRWKyZy7eEruLK2B09uzREQu6tV BNhOcjhyMMg6w== From: Sasha Levin To: patches@lists.linux.dev Cc: Dmytro Maluka , Kevin Tian , Lu Baolu , Joerg Roedel , Sasha Levin Subject: [PATCH 5.15 067/164] iommu/vt-d: Flush cache for PASID table before using it Date: Sat, 28 Feb 2026 13:13:26 -0500 Message-ID: <20260228181505.1600663-67-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260228181505.1600663-1-sashal@kernel.org> References: <20260228181505.1600663-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit From: Dmytro Maluka [ Upstream commit 22d169bdd2849fe6bd18c2643742e1c02be6451c ] When writing the address of a freshly allocated zero-initialized PASID table to a PASID directory entry, do that after the CPU cache flush for this PASID table, not before it, to avoid the time window when this PASID table may be already used by non-coherent IOMMU hardware while its contents in RAM is still some random old data, not zero-initialized. Fixes: 194b3348bdbb ("iommu/vt-d: Fix PASID directory pointer coherency") Signed-off-by: Dmytro Maluka Reviewed-by: Kevin Tian Link: https://lore.kernel.org/r/20251221123508.37495-1-dmaluka@chromium.org Signed-off-by: Lu Baolu Signed-off-by: Joerg Roedel Signed-off-by: Sasha Levin --- drivers/iommu/intel/pasid.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/iommu/intel/pasid.c b/drivers/iommu/intel/pasid.c index 589b97ff5433c..fd60e7ec625ea 100644 --- a/drivers/iommu/intel/pasid.c +++ b/drivers/iommu/intel/pasid.c @@ -268,6 +268,9 @@ static struct pasid_entry *intel_pasid_get_entry(struct device *dev, u32 pasid) if (!entries) return NULL; + if (!ecap_coherent(info->iommu->ecap)) + clflush_cache_range(entries, VTD_PAGE_SIZE); + /* * The pasid directory table entry won't be freed after * allocation. No worry about the race with free and @@ -279,10 +282,8 @@ static struct pasid_entry *intel_pasid_get_entry(struct device *dev, u32 pasid) free_pgtable_page(entries); goto retry; } - if (!ecap_coherent(info->iommu->ecap)) { - clflush_cache_range(entries, VTD_PAGE_SIZE); + if (!ecap_coherent(info->iommu->ecap)) clflush_cache_range(&dir[dir_index].val, sizeof(*dir)); - } } return &entries[index]; -- 2.51.0