From ef195e8a7f43924b9979b2cd81ac7fa54f24bb3c Mon Sep 17 00:00:00 2001

From: "David E. Box" <david.e.box@linux.intel.com>

Date: Tue, 17 Aug 2021 15:40:17 -0700

Subject: [PATCH] platform/x86: intel_pmt_telemetry: Ignore zero sized entries

Git-commit: ef195e8a7f43924b9979b2cd81ac7fa54f24bb3c

Patch-mainline: v5.15-rc1

References: bsc#1196591

Some devices may expose non-functioning entries that are reserved for

future use. These entries have zero size. Ignore them during probe.

Signed-off-by: David E. Box <david.e.box@linux.intel.com>

Link: https://lore.kernel.org/r/20210817224018.1013192-5-david.e.box@linux.intel.com

Reviewed-by: Hans de Goede <hdegoede@redhat.com>

Signed-off-by: Hans de Goede <hdegoede@redhat.com>

Acked-by: Takashi Iwai <tiwai@suse.de>

---

 drivers/platform/x86/intel/pmt/telemetry.c | 8 ++++++++

 1 file changed, 8 insertions(+)

diff --git a/drivers/platform/x86/intel/pmt/telemetry.c b/drivers/platform/x86/intel/pmt/telemetry.c

index a58843360fbf..38d52651c572 100644

--- a/drivers/platform/x86/intel/pmt/telemetry.c

+++ b/drivers/platform/x86/intel/pmt/telemetry.c

@@ -61,6 +61,14 @@ static int pmt_telem_header_decode(struct intel_pmt_entry *entry,

 	/* Size is measured in DWORDS, but accessor returns bytes */

 	header->size = TELEM_SIZE(readl(disc_table));

+	/*

+	 * Some devices may expose non-functioning entries that are

+	 * reserved for future use. They have zero size. Do not fail

+	 * probe for these. Just ignore them.

+	 */

+	if (header->size == 0)

+		return 1;

+

 	return 0;

 }

-- 

2.31.1