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 73AFD38F623 for ; Sat, 28 Feb 2026 18:08:52 +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=1772302132; cv=none; b=JDHPmZGiriMFO+Azktr9+9/ouJLIH2tIMzmzMCOZKK4+xY8NI2g5o5PJTEuQw7ihkniA3q7pQINXoCzoFtPKtCjC56mrFG5o9T0wpWgKzUhDjnXdo0ROHcC/uMeJg0/FMILHMcSTi4lOkupjVH00d6lOwWs/i00kPE4qFF7ZVts= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772302132; c=relaxed/simple; bh=px3BH+gpChuei5n+8twfbfGjr4i6zwn0gorBNR3OxVo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=od09k/kvWaG4qNAmCbKqYoP99BBl2H7EAbwR+sUmYIyQqUnsudlZ3NXz/dd9647Fj6cIvuc4jXIybx3mY9gWXIbWwkBAE2RaUMEdYT1dLfpsDVvmBV1/rqgtCgAZbNKwG+ewyNUfj2hLrIIhvot42vuwKCjVSSF+IO+q8VZFyV8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Ve70CTkd; 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="Ve70CTkd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id AA2BCC116D0; Sat, 28 Feb 2026 18:08:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772302132; bh=px3BH+gpChuei5n+8twfbfGjr4i6zwn0gorBNR3OxVo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Ve70CTkdnQQfq5zjknJMFEyalofxqJkauuizeY/QegPUjawuRLzbv1OFKJnrLEniG T7Y78Ue2i7s7jVembU/dkxyImeagJzoptk+taajFlKrsfGZ2dbr4/587zni/J7rkdP TZBs+uKRsdJPCgOiHyuvGP/j9tiViUSOmCHZnnQ1bcqE6Zzts86wCYR+Si82sEyG1x c8ZylxIUG/3pi95XrZMbqz7Qk2kdp9ftjgeAW72Ffi7OnZP7Pu50dru8/4KzL5zK9J taolHoElMGbNBgBdCM2x5vAvjVdAZRkM+JQyxONzZfU+LeagZ7fd9Ck+1ed5740Atq yKGo41PnrigVQ== From: Sasha Levin To: patches@lists.linux.dev Cc: Dmytro Maluka , Kevin Tian , Lu Baolu , Joerg Roedel , Sasha Levin Subject: [PATCH 6.6 123/283] iommu/vt-d: Flush cache for PASID table before using it Date: Sat, 28 Feb 2026 13:04:25 -0500 Message-ID: <20260228180709.1583486-123-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260228180709.1583486-1-sashal@kernel.org> References: <20260228180709.1583486-1-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 8faa93cffac45..07c8b0df8e2a8 100644 --- a/drivers/iommu/intel/pasid.c +++ b/drivers/iommu/intel/pasid.c @@ -207,6 +207,9 @@ 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 @@ -218,10 +221,8 @@ 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