From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f195.google.com (mail-pf1-f195.google.com [209.85.210.195]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C74E033D6DF for ; Wed, 26 Nov 2025 16:08:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.195 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764173337; cv=none; b=pAofq7Z0DJ2NzzJ1hcwAeAJwJ7hsSfEkLtaVm29Ty3lVxXGwNzlpLFE4ptYgPGkPIYAeiwqm9tan3SA8gSxieN5E6ICvudvK7E3jMPPMkcA95dv5ozcjD801r92JaqN+RXe0GWhCrKZcRg+Pe26zHOWT1BvrvnUGHI0WTJlCabc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764173337; c=relaxed/simple; bh=7I2EQS/O47z6XkwcLP1Gg8ZRDwtXdZe/P9q5/pdULpQ=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=LS6bvBmeMdeIiHtWRZKzDT4/C8StX2KAMRPQaohNFJ4cfgaESvn0vlj8lWnvR7Nq8hph0FhQN9Jr4E9OmICqBadaLchM60yutdLurbDuIvQNmgDp2BGRH+Ys5yo7+WeDcPgjXATU/hHm1PqurYBc3glrDJL1lVF9Dzg6HZGzjRQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=eLfFird3; arc=none smtp.client-ip=209.85.210.195 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="eLfFird3" Received: by mail-pf1-f195.google.com with SMTP id d2e1a72fcca58-7bab7c997eeso7764782b3a.0 for ; Wed, 26 Nov 2025 08:08:52 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1764173330; x=1764778130; darn=lists.linux.dev; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=0w85V/n6/PltUzl9FbkvTGvY3LknN/8DxQ32r6IxQUM=; b=eLfFird3fdLIHzS8gW3IyCIXQPNznTeCIc6c3nP60+BSOEFMe2vc9WNt/YY0nx+BOk OiTyDpJ6fOTh7KW1MSZLNDEFXF/3aX1CU5c5lfx5W6k0UZ9wtC1Iz1ncVHf7Dm9Mpx+t hQFQuPZgxSI+vHWE6clSbB6BZg9CyWDaTYeEkxuRUmDKLIkrbSdkAChPx9q8a4GEzoDP 0+JB76enYo3vA/XF95KPEZFlU8hCHck7/diMSjB+s/oof2brO4/lO+kQ3xChL8EGb5Gk a+SXNhHRdML/L9Zvw9WTPWiywPn+uh6iiEng/3HKE1pDNPH07yUa8fIswZ8IobfE9W4c uTwQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1764173330; x=1764778130; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=0w85V/n6/PltUzl9FbkvTGvY3LknN/8DxQ32r6IxQUM=; b=syck3nGKbyAI5r9mGteufKnm7ynI7fbq2c7SFwOHW/cMVZH6se4YSo+ZwSVOvwKGIH bAV7M4feNt0CyZLoZli7N5t/O5w5472lk0tzhviiY6ewIjUAwZg1/x5qo0WGqpyImT/0 dofn4HDXcrONnAQhV6wki5WK7WEjB2uOm/rA5BUZ4Jvb6s9KnmWfGVOAf3/J/yB5CP+7 bPLR9LYDQXu28dus7fwRH3kNE8sxJu/G6cRH0cs69GeIglzIeJvb0Hia1w4h7N/GYUHF wTaM5Tyd4P16GB2jdi3zH3GxrGQIbHO6E3/QFUECqggjBbhRkdMQ5waqBRE/9cvVwKeo zYSg== X-Forwarded-Encrypted: i=1; AJvYcCUc3Na/acaFv+laXff9i735t650XxLohTM0dqK1xzzN+wwFpOLNEuDB//8eEihWACal7aOw@lists.linux.dev X-Gm-Message-State: AOJu0YwdinIszVuyb3PB1MR4YlgbonwI9slzYXavRjLoEhI19CyCl6Se HG9mmqScMU85GEXc+dxOyjeCJgJ36aycen59LHRBQyvrq54nzlG0IFZA X-Gm-Gg: ASbGnctFj6B/gwVdaGy1s1l0D3Mz9g3vlv6FF2aJ/Si4zaRLrEBBFpmwlBX4Xs7ZhKV 94GeL7Db7RGVPdNoF/gzUTJiR6K0BK2/dTgRuLwpKEAYAh/V7O4d2Y9/75eP+5h5VtEVT01oUco stOWI+/MFC8V0TeTvs+saBI5K6ACs9Od0VpGgfYPkQSsaR6dargEiaX2zCbas6ojb1RkWzgNuoj nxkU5pNUJrPk6AE9Q0j9ox4LT39zdiAOL5Iq7wVCbB1J4wvctEFFIM2hWOyeBMSs592yP5b9pZe YaAlLFwQhKPenRPuuWWXJE+7Mp3406pb6XMP1kbWM28Jk375R01aOjvKky7bgqqFP57TP017PsF KalW+WrhWW66OsQwHPN2c9wFJTAi4UIX/tjq+/u0A5iM8pizVMrS2QV4nisQ9LGHFuUpJTTJ1gx Wpl1fo7PjKr12uwaed3nBa5hDA+TFjwQ== X-Google-Smtp-Source: AGHT+IEebVkUKBP+U1i9Oqi7Ort6BI2gg0wHmeA+Y9t88Utsg2k3h8rxgk1fLNRybEyKRORRW5br6g== X-Received: by 2002:a05:6a00:2d88:b0:7b9:ef46:ec70 with SMTP id d2e1a72fcca58-7c58e50c16emr18224646b3a.23.1764173330206; Wed, 26 Nov 2025 08:08:50 -0800 (PST) Received: from fedora ([103.120.31.122]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-7c3f0243b3csm21831681b3a.36.2025.11.26.08.08.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 26 Nov 2025 08:08:49 -0800 (PST) From: Ankit Khushwaha To: Andrew Morton , Mike Rapoport , Peter Xu , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Suren Baghdasaryan , Michal Hocko , Nathan Chancellor , Nick Desaulniers , Bill Wendling , Justin Stitt Cc: Shuah Khan , linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, llvm@lists.linux.dev, Ankit Khushwaha Subject: [PATCH] selftests/mm/uffd: initialize char variable to Null Date: Wed, 26 Nov 2025 21:38:30 +0530 Message-ID: <20251126160830.52124-1-ankitkhushwaha.linux@gmail.com> X-Mailer: git-send-email 2.52.0 Precedence: bulk X-Mailing-List: llvm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit In "uffd-stress.c" & "uffd-unit-tests.c". address of char variable having garbage value (uninitialized) is passed to 'write' syscall triggers warning. uffd-stress.c:246:39: warning: variable 'c' is uninitialized when passed as a const pointer argument here [-Wuninitialized-const-pointer] uffd-unit-tests.c:581:31: warning: variable 'c' is uninitialized when passed as a const pointer argument here [-Wuninitialized-const-pointer] so the fix is to assign char variable to '\0' to prevent writing of garbage value. Signed-off-by: Ankit Khushwaha --- this warning is raised with clang version 21.1.5 (Fedora 21.1.5-1.fc43). --- tools/testing/selftests/mm/uffd-stress.c | 2 +- tools/testing/selftests/mm/uffd-unit-tests.c | 8 ++++---- 2 files changed, 5 insertions(+), 5 deletions(-) diff --git a/tools/testing/selftests/mm/uffd-stress.c b/tools/testing/selftests/mm/uffd-stress.c index b51c89e1cd1a..700fbaa18d44 100644 --- a/tools/testing/selftests/mm/uffd-stress.c +++ b/tools/testing/selftests/mm/uffd-stress.c @@ -241,7 +241,7 @@ static int stress(struct uffd_args *args) return 1; for (cpu = 0; cpu < gopts->nr_parallel; cpu++) { - char c; + char c = '\0'; if (bounces & BOUNCE_POLL) { if (write(gopts->pipefd[cpu*2+1], &c, 1) != 1) err("pipefd write error"); diff --git a/tools/testing/selftests/mm/uffd-unit-tests.c b/tools/testing/selftests/mm/uffd-unit-tests.c index f917b4c4c943..f4807242c5b2 100644 --- a/tools/testing/selftests/mm/uffd-unit-tests.c +++ b/tools/testing/selftests/mm/uffd-unit-tests.c @@ -543,7 +543,7 @@ static void uffd_minor_test_common(uffd_global_test_opts_t *gopts, bool test_col { unsigned long p; pthread_t uffd_mon; - char c; + char c = '\0'; struct uffd_args args = { 0 }; args.gopts = gopts; @@ -759,7 +759,7 @@ static void uffd_sigbus_test_common(uffd_global_test_opts_t *gopts, bool wp) pthread_t uffd_mon; pid_t pid; int err; - char c; + char c = '\0'; struct uffd_args args = { 0 }; args.gopts = gopts; @@ -819,7 +819,7 @@ static void uffd_events_test_common(uffd_global_test_opts_t *gopts, bool wp) pthread_t uffd_mon; pid_t pid; int err; - char c; + char c = '\0'; struct uffd_args args = { 0 }; args.gopts = gopts; @@ -1125,7 +1125,7 @@ uffd_move_test_common(uffd_global_test_opts_t *gopts, { unsigned long nr; pthread_t uffd_mon; - char c; + char c = '\0'; unsigned long long count; struct uffd_args args = { 0 }; char *orig_area_src = NULL, *orig_area_dst = NULL; -- 2.52.0