From nobody Mon Feb 9 08:28:26 2026 Received: from mail-ot1-f66.google.com (mail-ot1-f66.google.com [209.85.210.66]) (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 4604B30C353 for ; Wed, 14 Jan 2026 02:00:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.66 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768356018; cv=none; b=pkKmalx/MoYcitPh82aawwqr6qU7+Q+fWhwaPm2wG3c/0dYUnrloktKr4BJyczlboi8Sg2BPKu8HRgfxZQe+taPfKOFolr/8ko0TS9lpsvlhfHF4RdmRLxtmdfQsEla06aRefiqFEyE3zuOaw0l27NcTGpsZaJdgtpWOp80ReHY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768356018; c=relaxed/simple; bh=Odcd6YwIhhQurU/smbiY8MbtQ0MmiwPiMOaa2h2/m5Y=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=pfjuL8fljRlWzdDSfeXNc7oFmUgO+2yg7Mm5TyBD/0pq7b6/zaBq9bo7WSIuD3mIE0G0ZKdsjKNbLa1DcUpkygVN6Asqa11E281exV3Ne+5jAbIYYXwdXeEFTjHazBRARB7YF5V2b4+aLy/bLc/SoXKPwEefYpWL9l+Juuz66DU= 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=k/IKgAfg; arc=none smtp.client-ip=209.85.210.66 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="k/IKgAfg" Received: by mail-ot1-f66.google.com with SMTP id 46e09a7af769-7c750b10e14so3517256a34.2 for ; Tue, 13 Jan 2026 18:00:16 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1768356015; x=1768960815; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=ekbNT1OfK8aGhMhy2w3gZ5CU/UUE92pgkgzIatZ/Ils=; b=k/IKgAfgIhbh26gP8KBdnhuqdkAjwlY/VdMEv/VeqQA9zBJTreXdzrW5PMlmq7gvRR aAzpWJsjZR4LAVxw4QqpjYKzNusZDMhwUN/tQI9nrZXsqAcPIq/GxQ+jdXVbP4o8us8k TNIS93ITUhPMr7Wqai+y+7QXXs4SVhsIUaTK+wotWGmCavjUVFIBaH3CLOaGdO/kt91h Q4NRcdPiIUIambyZ6E4vxgen0SkJyJ2P697l3sx2rSDTh2egKmd71qvV3igz0qZzTeoX CrfzYKmtYN0IgsgANLU/Gy1ahIm7JuGZHXhYlpXHSuU1VR2VfOaHJ29GPdyRhITPzQ0B PwKw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1768356015; x=1768960815; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=ekbNT1OfK8aGhMhy2w3gZ5CU/UUE92pgkgzIatZ/Ils=; b=MKNpnu8Cln44uYOQWe0eVHDOqZ0fxDTaP60CTrImonZ6EeOBoUCBgLoh/AMEnlshc+ Bunh3cFnzGnVTYLM0iPGuUSMP8NpNBotQeI5Z0+AB3aEipls/lWqJJnRF9iYFVYyw+wo Wn1Irk21aqaeO9FU38rjx7GN2AsdMpLHsJGNAisNtIJyDm2wumeiamSisXfHoiUjbea8 526XQAHyjNrdNmwMu3DltuGw0alIvK7IfHok13heP4Ex/ZCszEDFStwwc0twNhcR594i bP9J451iUEOyU4kqYjdFE5OPu1OkD35CBBHox0eRcwspSfiD3iHyMDDOCiDP8gl0+YiJ i8QQ== X-Forwarded-Encrypted: i=1; AJvYcCXNc6ACCp/9ukridHJy3fZ11k+Gnw+vUasIyAIiKkBEuDlt70imxrm4VqD5u7Wa/G8euzncWNpRlDiUgpI=@vger.kernel.org X-Gm-Message-State: AOJu0YxarXw+vnrKOoxtGvC/ygHmm3qQd67vXKryfWFFX8D/MIFjCB0J hQVld4cUyxDlhmU3LHCd/6pb7zaRiatTwK2+VlpT9xo2W7Q57d9xf39E X-Gm-Gg: AY/fxX4OZ9JJ4jqCRySm2kmwiY5Yl7zL9heWQXlUwSeXvs+rQYDXlQfj5oXUNz6ILoE AgxDwajeoP9VZrgyf44d8B/DHXofpzfKsImmtSaH7zu6lnvGib4/NqfvaKEJwtAiPea1FnHCS1C g1tUjfrJ7pG31BEt8AzAtcA6CQZCGKhUdGItqu7lCNrmaX6/UD7Gwv0tCCmWpwef9igfVkgPYgK eZ5nyJRtiuM/vtMArM0MPb1FxmeRKCGtY+Xf6B2e/QcQKuORad/QhxkuUp3H2pCY0O8Fx6KMywl 02OoKRwQAQyOruJOdNf3gllPc5CEYlfx5HT+h+LtnshFKYyjZPX+i5IuPXEHGlYX8at4cNzQcQb 2GjEc4+1hthaJjyCh2FcDR08QzauF+zkbnpcqJ9SxzY9IBvHySpOpgp0Vdu0zHvX1Y5h00Sikzc N3DL9yDfLa7TlZEHCsbKRV7x1L5GXHO2mjPXgYap2Bg7aisGM= X-Received: by 2002:a05:6830:4c82:b0:7ce:2b34:deca with SMTP id 46e09a7af769-7cfcb66f5fdmr225302a34.28.1768356015134; Tue, 13 Jan 2026 18:00:15 -0800 (PST) Received: from frodo (c-98-38-17-99.hsd1.co.comcast.net. [98.38.17.99]) by smtp.googlemail.com with ESMTPSA id 46e09a7af769-7ce478ee883sm17634530a34.28.2026.01.13.18.00.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 13 Jan 2026 18:00:14 -0800 (PST) From: Jim Cromie To: gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org Cc: Jim Cromie , Jason Baron , =?UTF-8?q?=C5=81ukasz=20Bartosik?= , Louis Chauvet , Bagas Sanjaya , Dave Airlie , Daniel Vetter , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , dri-devel@lists.freedesktop.org, Petr Mladek , Shuah Khan , linux-doc@vger.kernel.org, Steven Rostedt , "Liam R. Howlett" Subject: [PATCH v8 23/31] dyndbg: check DYNAMIC_DEBUG_CLASSMAP_DEFINE args at compile-time Date: Tue, 13 Jan 2026 18:57:39 -0700 Message-ID: <20260114015815.1565725-24-jim.cromie@gmail.com> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260114015815.1565725-1-jim.cromie@gmail.com> References: <20260114015815.1565725-1-jim.cromie@gmail.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Add __DYNAMIC_DEBUG_CLASSMAP_CHECK to implement the following arg-checks at compile-time: 0 <=3D _base < 63 class_names is not empty class_names[0] is a string (class_names.length + _base) < 63 These compile-time checks will prevent several simple misuses, and will issue obvious errors if violated. 4 such examples are added to test_dynamic_debug_submod.ko, and will fail compilation if -DDD_MACRO_ARGCHECK is added to cflags. This wouldn't be a useful CONFIG_ item, since it breaks the build. Signed-off-by: Jim Cromie --- include/linux/dynamic_debug.h | 9 +++++++++ lib/test_dynamic_debug.c | 13 ++++++++++++- 2 files changed, 21 insertions(+), 1 deletion(-) diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h index ad3dc10ff03a..d8bfd19efde6 100644 --- a/include/linux/dynamic_debug.h +++ b/include/linux/dynamic_debug.h @@ -180,6 +180,14 @@ struct _ddebug_class_param { * __pr_debug_cls(22, "no such class"); compiles but is not reachable */ =20 +#define __DYNAMIC_DEBUG_CLASSMAP_CHECK(_clnames, _base) \ + static_assert(((_base) >=3D 0 && (_base) < _DPRINTK_CLASS_DFLT), \ + "_base must be in 0..62"); \ + static_assert(ARRAY_SIZE(_clnames) > 0, \ + "classnames array size must be > 0"); \ + static_assert((ARRAY_SIZE(_clnames) + (_base)) < _DPRINTK_CLASS_DFLT, \ + "_base + classnames.length exceeds range") + /** * DYNAMIC_DEBUG_CLASSMAP_DEFINE - define debug classes used by a module. * @_var: name of the classmap, exported for other modules coordinated u= se. @@ -193,6 +201,7 @@ struct _ddebug_class_param { */ #define DYNAMIC_DEBUG_CLASSMAP_DEFINE(_var, _mapty, _base, ...) \ static const char *_var##_classnames[] =3D { __VA_ARGS__ }; \ + __DYNAMIC_DEBUG_CLASSMAP_CHECK(_var##_classnames, (_base)); \ extern struct _ddebug_class_map _var; \ struct _ddebug_class_map __aligned(8) __used \ __section("__dyndbg_class_maps") _var =3D { \ diff --git a/lib/test_dynamic_debug.c b/lib/test_dynamic_debug.c index 1ba4be9a403a..b2bdfdfb6ba1 100644 --- a/lib/test_dynamic_debug.c +++ b/lib/test_dynamic_debug.c @@ -133,7 +133,7 @@ DYNAMIC_DEBUG_CLASSMAP_PARAM(level_num, p); * Enable with -Dflag on compile to test overlapping class-id range * detection. This should warn on modprobes. */ -DYNDBG_CLASSMAP_DEFINE(classid_range_conflict, 0, D2_CORE + 1, "D3_CORE"); +DYNAMIC_DEBUG_CLASSMAP_DEFINE(classid_range_conflict, 0, D2_CORE + 1, "D3_= CORE"); #endif =20 #else /* TEST_DYNAMIC_DEBUG_SUBMOD */ @@ -146,8 +146,19 @@ DYNDBG_CLASSMAP_DEFINE(classid_range_conflict, 0, D2_C= ORE + 1, "D3_CORE"); DYNAMIC_DEBUG_CLASSMAP_USE(map_disjoint_bits); DYNAMIC_DEBUG_CLASSMAP_USE(map_level_num); =20 +#if defined(DD_MACRO_ARGCHECK) +/* + * Exersize compile-time arg-checks in DYNAMIC_DEBUG_CLASSMAP_DEFINE. + * These will break compilation. + */ +DYNAMIC_DEBUG_CLASSMAP_DEFINE(fail_base_neg, 0, -1, "NEGATIVE_BASE_ARG"); +DYNAMIC_DEBUG_CLASSMAP_DEFINE(fail_base_big, 0, 100, "TOOBIG_BASE_ARG"); +DYNAMIC_DEBUG_CLASSMAP_DEFINE(fail_str_type, 0, 0, 1 /* not a string */); +DYNAMIC_DEBUG_CLASSMAP_DEFINE(fail_emptyclass, 0, 0 /* ,empty */); #endif =20 +#endif /* TEST_DYNAMIC_DEBUG_SUBMOD */ + /* stand-in for all pr_debug etc */ #define prdbg(SYM) __pr_debug_cls(SYM, #SYM " msg\n") =20 --=20 2.52.0