From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=217.140.110.172 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794567306; b=rJk0NDf3+1YH+qumur460ZJ966c2v2VqEKVqXl6csijBm6ewbh8Uroizap1fadYbaymT 5S2ijq68/+Yl9hczCwdCtP+hCr4mGM2if43T4C8SGLiHxO5/oktY7STai8ngoHvXFn6Is nNrAzZB7dhmzRy73OQ+OhvZNc3az6UzYfZ5oZSDNg1jXoNDsVVXTwRn1UImHCpQ68ISEf oIG/aRwD5YxM+um+r+gBlIk57cBwVlBElnKYn3Ib8CYomygzBCRbKEXoxv79ffGSr+glS FMdenjts1l47mbswO4sTvpfTuPoXIbL+BL8+/fs2hvgpp9xOGGJbFCr9+q8V5GeC+EA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794567306; h=DMARC-Filter:Received:Received:DKIM-Signature:From:Date:Subject: MIME-Version:Content-Type:Content-Transfer-Encoding:Message-Id: References:In-Reply-To:To:Cc:X-Mailer:X-Developer-Signature: X-Developer-Key; bh=QUYBNBZj+lW+OPNvW2qKBQAyQ8N2obK55MwOVcAaI5E=; b=p3hKMDeqLAXDfuoBoHpuf5tEf4U0IkVtz88Q3+zP91JOe2xaX26o+UYKIb0dXfHm5pW4 UWgE7BNRK3zxUui0cjqhRJ2CWncqGOAlTQeZj+B6greOMnyCQsYkEUTsxT2lyNL/RkPAG dtTd5oXX+rxAZZMTnqMEFSYzNRrjvS/wFsvbYCScKwPwYgL2Zsc2/kT7RdWgZHN+8gSmo DMH32R3UwGI3Pkyiu/A9tJ0b3W9koOH+3+yFkIkcl6ema+OUnRUElJIOFP1z6KehFhVrw A1BXk1L1Qf1kH5mqk0junZo41Ac8CZls/F/KFgyhPErUKANP1FD6B7QpXjSqAhHrd1w== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass header.d=arm.com header.i=@arm.com header.a=rsa-sha256 header.s=foss header.b=bI34F5OW; arc=none smtp.remote-ip=217.140.110.172 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id D33E0606A8A4; Fri, 13 Nov 2026 10:55:05 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org D33E0606A8A4 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.a=rsa-sha256 header.s=foss header.b=bI34F5OW Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 64E5F1BF3; Fri, 13 Nov 2026 02:55:02 -0800 (PST) Received: from e132581.arm.com (unknown [10.2.196.114]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id CC1813F673; Fri, 13 Nov 2026 02:55:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1794567305; bh=PcQuDLM+ZyjAtHUeLq4+Pe+fYs9lcsAwvJZO4FQEXHg=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=bI34F5OWssnZ1R6O+UisrYaLXA1gzTBsCX1pYgHc19eZYJwjrVgQMHlt+dJnG/gqt H/V3xdvbBYbfhVtpHRy7KzM3pJT6imwueHIrOLcgK3123bO8l6Nq7LZC9iOGgtpofi 49ATo9KkZE6e9inu4PZiIo5wUnpNoWWGd83GEXHw= From: Leo Yan Date: Fri, 13 Nov 2026 10:54:52 +0000 Subject: [PATCH 1/3] perf cs-etm: Initialize the Thumb instruction buffer X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20261113-perf_fix_gcc15_failure-v1-1-eae592c5ff64@arm.com> References: <20261113-perf_fix_gcc15_failure-v1-0-eae592c5ff64@arm.com> In-Reply-To: <20261113-perf_fix_gcc15_failure-v1-0-eae592c5ff64@arm.com> To: Arnaldo Carvalho de Melo , Namhyung Kim , James Clark , Mike Leach , Suzuki K Poulose , Ian Rogers , Adrian Hunter , Robert Walker Cc: Arnaldo Carvalho de Melo , coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org, linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org, Leo Yan X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=ed25519-sha256; t=1794567301; l=1422; i=leo.yan@arm.com; s=20250604; h=from:subject:message-id; bh=PcQuDLM+ZyjAtHUeLq4+Pe+fYs9lcsAwvJZO4FQEXHg=; b=eh8Mpnhp/Gw8xKFd1DU0kzymunaq3Q280Cqkf9l5gGrIGlfcoEZFxb0b+P8pCaIhLRizoSQ6y uFbrLqp3lnfDRChJ3UQerndIOGW78D65sdxX3LMfKYfzM+kuS7BvKTP X-Developer-Key: i=leo.yan@arm.com; a=ed25519; pk=k4BaDbvkCXzBFA7Nw184KHGP5thju8lKqJYIrOWxDhI= cs_etm__frontend_mem_access() can return zero or a short read without fully initializing instrBytes. cs_etm__t32_instr_size() nevertheless inspects its second byte. With CORESIGHT=1 and -O3, GCC 15.2.0 reports: error: 'instrBytes' may be used uninitialized Zero-initialize the buffer to avoid reading uninitialized stack data when instruction memory is unavailable and fix the build failure. Reported-by: Ian Rogers Closes: https://lore.kernel.org/linux-perf-users/20261030-perf_cs_etm_fix_non_taken-v3-0-7629b52ab047@arm.com/T/#m64fb81c665214b79883d9be815b40ac5f6669628 Fixes: a7ee4d625ede ("perf cs-etm: Support for ARM A32/T32 instruction sets in CoreSight trace") Signed-off-by: Leo Yan --- tools/perf/util/cs-etm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c index 3e01b401ca6f3a08f44bb69204317efaf2fa18d0..25f12bd110934a204d79244f45317085b7a81666 100644 --- a/tools/perf/util/cs-etm.c +++ b/tools/perf/util/cs-etm.c @@ -1369,7 +1369,7 @@ static inline int cs_etm__t32_instr_size(struct cs_etm_queue *etmq, struct cs_etm_traceid_queue *tidq, struct cs_etm_packet *packet, u64 addr) { - u8 instrBytes[2]; + u8 instrBytes[2] = { 0 }; cs_etm__frontend_mem_access(etmq, tidq, packet, addr, ARRAY_SIZE(instrBytes), instrBytes); -- 2.34.1