linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Wen Yang <wen.yang@linux.dev>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Jon Hunter <jonathanh@nvidia.com>
Cc: stable@vger.kernel.org, linux-kernel@vger.kernel.org,
	Pierre Gondois <pierre.gondois@arm.com>,
	Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
	Sudeep Holla <sudeep.holla@arm.com>,
	Wen Yang <wen.yang@linux.dev>
Subject: [PATCH 6.1 03/10] cacheinfo: Check 'cache-unified' property to count cache leaves
Date: Tue, 21 Oct 2025 01:36:17 +0800	[thread overview]
Message-ID: <20251020173624.20228-4-wen.yang@linux.dev> (raw)
In-Reply-To: <20251020173624.20228-1-wen.yang@linux.dev>

From: Pierre Gondois <pierre.gondois@arm.com>

[ Upstream commit de0df442ee49cb1f6ee58f3fec5dcb5e5eb70aab ]

The DeviceTree Specification v0.3 specifies that the cache node
'[d-|i-|]cache-size' property is required. The 'cache-unified'
property is specifies whether the cache level is separate
or unified.

If the cache-size property is missing, no cache leaves is accounted.
This can lead to a 'BUG: KASAN: slab-out-of-bounds' [1] bug.

Check 'cache-unified' property and always account for at least
one cache leaf when parsing the device tree.

[1] https://lore.kernel.org/all/0f19cb3f-d6cf-4032-66d2-dedc9d09a0e3@linaro.org/

Reported-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
Tested-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230104183033.755668-4-pierre.gondois@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Wen Yang <wen.yang@linux.dev>
---
 drivers/base/cacheinfo.c | 37 ++++++++++++++++++++++++++-----------
 1 file changed, 26 insertions(+), 11 deletions(-)

diff --git a/drivers/base/cacheinfo.c b/drivers/base/cacheinfo.c
index 480007210bcc..ab99b0f0d010 100644
--- a/drivers/base/cacheinfo.c
+++ b/drivers/base/cacheinfo.c
@@ -224,12 +224,9 @@ static int cache_setup_of_node(unsigned int cpu)
 	return 0;
 }
 
-int init_of_cache_level(unsigned int cpu)
+static int of_count_cache_leaves(struct device_node *np)
 {
-	struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
-	struct device_node *np = of_cpu_device_node_get(cpu);
-	struct device_node *prev = NULL;
-	unsigned int levels = 0, leaves = 0, level;
+	unsigned int leaves = 0;
 
 	if (of_property_read_bool(np, "cache-size"))
 		++leaves;
@@ -237,6 +234,28 @@ int init_of_cache_level(unsigned int cpu)
 		++leaves;
 	if (of_property_read_bool(np, "d-cache-size"))
 		++leaves;
+
+	if (!leaves) {
+		/* The '[i-|d-|]cache-size' property is required, but
+		 * if absent, fallback on the 'cache-unified' property.
+		 */
+		if (of_property_read_bool(np, "cache-unified"))
+			return 1;
+		else
+			return 2;
+	}
+
+	return leaves;
+}
+
+int init_of_cache_level(unsigned int cpu)
+{
+	struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
+	struct device_node *np = of_cpu_device_node_get(cpu);
+	struct device_node *prev = NULL;
+	unsigned int levels = 0, leaves, level;
+
+	leaves = of_count_cache_leaves(np);
 	if (leaves > 0)
 		levels = 1;
 
@@ -250,12 +269,8 @@ int init_of_cache_level(unsigned int cpu)
 			goto err_out;
 		if (level <= levels)
 			goto err_out;
-		if (of_property_read_bool(np, "cache-size"))
-			++leaves;
-		if (of_property_read_bool(np, "i-cache-size"))
-			++leaves;
-		if (of_property_read_bool(np, "d-cache-size"))
-			++leaves;
+
+		leaves += of_count_cache_leaves(np);
 		levels = level;
 	}
 
-- 
2.25.1


  parent reply	other threads:[~2025-10-20 17:37 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-10-20 17:36 [PATCH 6.1 v2 00/10] fix invalid sleeping in detect_cache_attributes() Wen Yang
2025-10-20 17:36 ` [PATCH 6.1 01/10] cacheinfo: Use RISC-V's init_cache_level() as generic OF implementation Wen Yang
2025-10-20 17:36 ` [PATCH 6.1 02/10] cacheinfo: Return error code in init_of_cache_level() Wen Yang
2025-10-20 17:36 ` Wen Yang [this message]
2025-10-20 17:36 ` [PATCH 6.1 04/10] ACPI: PPTT: Remove acpi_find_cache_levels() Wen Yang
2025-10-20 17:36 ` [PATCH 6.1 05/10] ACPI: PPTT: Update acpi_find_last_cache_level() to acpi_get_cache_info() Wen Yang
2025-10-20 17:36 ` [PATCH 6.1 06/10] arch_topology: Build cacheinfo from primary CPU Wen Yang
2025-10-20 17:36 ` [PATCH 6.1 07/10] cacheinfo: Initialize variables in fetch_cache_info() Wen Yang
2025-10-20 17:36 ` [PATCH 6.1 08/10] cacheinfo: Fix LLC is not exported through sysfs Wen Yang
2025-10-20 17:36 ` [PATCH 6.1 09/10] drivers: base: cacheinfo: Update cpu_map_populated during CPU Hotplug Wen Yang
2025-10-20 17:36 ` [PATCH 6.1 10/10] arm64: tegra: Update cache properties Wen Yang

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20251020173624.20228-4-wen.yang@linux.dev \
    --to=wen.yang@linux.dev \
    --cc=gregkh@linuxfoundation.org \
    --cc=jonathanh@nvidia.com \
    --cc=krzysztof.kozlowski@linaro.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=pierre.gondois@arm.com \
    --cc=stable@vger.kernel.org \
    --cc=sudeep.holla@arm.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).