From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 1CB17C021B2 for ; Tue, 25 Feb 2025 14:27:24 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 9445B10E6DF; Tue, 25 Feb 2025 14:27:23 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=bootlin.com header.i=@bootlin.com header.b="UxkQG5db"; dkim-atps=neutral Received: from relay4-d.mail.gandi.net (relay4-d.mail.gandi.net [217.70.183.196]) by gabe.freedesktop.org (Postfix) with ESMTPS id 5355410E6DF; Tue, 25 Feb 2025 14:27:22 +0000 (UTC) Received: by mail.gandi.net (Postfix) with ESMTPSA id 551F04442F; Tue, 25 Feb 2025 14:27:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1740493641; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ksF7rsjoy0iP9hn3MuB5+OiMn4k7YbnH9STHuf8uDAI=; b=UxkQG5dbGt+tSDyvxdAcaQ/tAsfRGtqmGzlChs+y3LOyB+9jX5jmFEjf72H1Ggym+k/DOC VB3I5kz6N9L6lZ4Mh3gX6BB+QcUYL30eCPPQlmM/XCzXNNTv7zYUs1vxP2lAVe0HjVAMu+ TC/x4zncUiWxlS3OzqnZYt7X24Q8eNWpD2rvWIVLIR0AGOKXHVRSdu306xqArgB4vKd4hT 8+BCY2Evu4EA03yeu6W6+0QVlzUv0bPTcDnzp5mBrxb4XerQG8iwEtOslZ3ZYh85v/LXrp 2AWL+RWAavDiFqE8FmNarRvJGRjPi8fPlPTtI1/SeqXW4VqM7lZHMIuMecz/7g== Date: Tue, 25 Feb 2025 15:27:19 +0100 From: Louis Chauvet To: Jim Cromie , linux-kernel@vger.kernel.org, jbaron@akamai.com, gregkh@linuxfoundation.org, ukaszb@chromium.org Cc: intel-gfx-trybot@lists.freedesktop.org, dri-devel@lists.freedesktop.org, amd-gfx@lists.freedesktop.org, intel-gvt-dev@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, daniel.vetter@ffwll.ch, tvrtko.ursulin@linux.intel.com, jani.nikula@intel.com, ville.syrjala@linux.intel.com Subject: Re: [PATCH 23/63] dyndbg: fail modprobe on ddebug_class_range_overlap() Message-ID: <6234628f-4085-40ad-b521-4590db2cb5f5@bootlin.com> Mail-Followup-To: Jim Cromie , linux-kernel@vger.kernel.org, jbaron@akamai.com, gregkh@linuxfoundation.org, ukaszb@chromium.org, intel-gfx-trybot@lists.freedesktop.org, dri-devel@lists.freedesktop.org, amd-gfx@lists.freedesktop.org, intel-gvt-dev@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, daniel.vetter@ffwll.ch, tvrtko.ursulin@linux.intel.com, jani.nikula@intel.com, ville.syrjala@linux.intel.com References: <20250125064619.8305-1-jim.cromie@gmail.com> <20250125064619.8305-24-jim.cromie@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20250125064619.8305-24-jim.cromie@gmail.com> X-GND-State: clean X-GND-Score: -100 X-GND-Cause: gggruggvucftvghtrhhoucdtuddrgeefvddrtddtgdekudelfecutefuodetggdotefrodftvfcurfhrohhfihhlvgemucfitefpfffkpdcuggftfghnshhusghstghrihgsvgenuceurghilhhouhhtmecufedtudenucesvcftvggtihhpihgvnhhtshculddquddttddmnecujfgurhepfffhvfevuffkfhggtggugfgjsehtkeertddttddunecuhfhrohhmpefnohhuihhsucevhhgruhhvvghtuceolhhouhhishdrtghhrghuvhgvthessghoohhtlhhinhdrtghomheqnecuggftrfgrthhtvghrnhepudeiffduffeivdejgfejheeuudekkedvjeeuffegfefghfffkeelgffgieevudejnecuffhomhgrihhnpegsohhothhlihhnrdgtohhmnecukfhppeeltddrkeelrdduieefrdduvdejnecuvehluhhsthgvrhfuihiivgepudenucfrrghrrghmpehinhgvthepledtrdekledrudeifedruddvjedphhgvlhhopehlohhuihhsqdgthhgruhhvvghtqdhlrghpthhophdpmhgrihhlfhhrohhmpehlohhuihhsrdgthhgruhhvvghtsegsohhothhlihhnrdgtohhmpdhnsggprhgtphhtthhopedugedprhgtphhtthhopehjihhmrdgtrhhomhhivgesghhmrghilhdrtghomhdprhgtphhtthhopehlihhnuhigqdhkvghrnhgvlhesvhhgvghrrdhkvghrnhgvlhdrohhrghdprhgtphhtthhopehjsggrrhhonhesrghkrghmrghirdgtohhmpdhrtghpthhtohepghhrvghgkhhhsehlihhnuhigfhhouhhnuggrthhiohhnr dhorhhgpdhrtghpthhtohepuhhkrghsiigssegthhhrohhmihhumhdrohhrghdprhgtphhtthhopehinhhtvghlqdhgfhigqdhtrhihsghotheslhhishhtshdrfhhrvggvuggvshhkthhophdrohhrghdprhgtphhtthhopegurhhiqdguvghvvghlsehlihhsthhsrdhfrhgvvgguvghskhhtohhprdhorhhgpdhrtghpthhtoheprghmugdqghhfgieslhhishhtshdrfhhrvggvuggvshhkthhophdrohhrgh X-GND-Sasl: louis.chauvet@bootlin.com X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Le 25/01/2025 à 07:45, Jim Cromie a écrit : > 1. All classes used by a module (declared DYNDBG_CLASSMAP_{DEFINE,USE} > by module code) must share 0..62 class-id space; ie their respective > base,+length reservations shouldn't overlap. Overlaps would lead to > unintended changes in ddebug enablements. > > Detecting these class-id range overlaps at compile-time would be ideal > but is not obvious how; failing at modprobe at least insures that the > developer sees and fixes the conflict. > > ddebug_class_range_overlap() implements the range check, accumulating > the reserved-ids as it examines each class. It probably should use > bitmaps. > > A previous commit reworked the modprobe callchain to allow failure, > now call ddebug_class_range_overlap() to check when classid conflicts > happen, and signal that failure. > > NB: this can only happen when a module defines+uses several classmaps, > > TBD: failing modprobe is kinda harsh, maybe warn and proceed ? > > test_dynamic_debug*.ko: > > If built with -DFORCE_CLASSID_CONFLICT_MODPROBE, the modules get 2 bad > DYNDBG_CLASS_DEFINE declarations, into parent and the _submod. These > conflict with one of the good ones in the parent (D2_CORE..etc), > causing the modprobe(s) to fail. TODO: do in submod only, since fail > of parent prevents submod from ever trying. > > Signed-off-by: Jim Cromie > --- > --- > lib/dynamic_debug.c | 30 ++++++++++++++++++++++++------ > lib/test_dynamic_debug.c | 11 ++++++++++- > 2 files changed, 34 insertions(+), 7 deletions(-) > > diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c > index 8afcd4111531..8e1e087e07c3 100644 > --- a/lib/dynamic_debug.c > +++ b/lib/dynamic_debug.c > @@ -1211,6 +1211,21 @@ static void ddebug_apply_params(const struct ddebug_class_map *cm, const char *m > } > } > > +static int ddebug_class_range_overlap(struct ddebug_class_map *cm, > + u64 *reserved_ids) > +{ > + u64 range = (((1ULL << cm->length) - 1) << cm->base); > + > + if (range & *reserved_ids) { > + pr_err("[%d..%d] on %s conflicts with %llx\n", cm->base, > + cm->base + cm->length - 1, cm->class_names[0], > + *reserved_ids); > + return -EINVAL; > + } > + *reserved_ids |= range; > + return 0; > +} > + > /* > * scan the named array: @_vec, ref'd from inside @_box, for the > * start,len of the sub-array of elements matching on ->mod_name; > @@ -1242,9 +1257,11 @@ static int ddebug_module_apply_class_maps(struct ddebug_table *dt, > struct ddebug_class_map *cm; > int i; > > - for_subvec(i, cm, &dt->info, maps) > + for_subvec(i, cm, &dt->info, maps) { > + if (ddebug_class_range_overlap(cm, reserved_ids)) > + return -EINVAL; > ddebug_apply_params(cm, cm->mod_name); > - > + } > vpr_info("module:%s attached %d classmaps\n", dt->mod_name, dt->info.maps.len); > return 0; > } > @@ -1255,10 +1272,11 @@ static int ddebug_module_apply_class_users(struct ddebug_table *dt, > struct ddebug_class_user *cli; > int i; > > - /* now iterate dt */ > - for_subvec(i, cli, &dt->info, users) > + for_subvec(i, cli, &dt->info, users) { > + if (ddebug_class_range_overlap(cli->map, reserved_ids)) > + return -EINVAL; > ddebug_apply_params(cli->map, cli->mod_name); > - > + } > vpr_info("module:%s attached %d classmap uses\n", dt->mod_name, dt->info.users.len); > return 0; > } > @@ -1311,11 +1329,11 @@ static int ddebug_add_module(struct _ddebug_info *di, const char *modname) > return rc; > } > } > + > mutex_lock(&ddebug_lock); > list_add_tail(&dt->link, &ddebug_tables); > mutex_unlock(&ddebug_lock); > > - Hi Jim, Strange line issues, can you squash it with the correct patch? Reviewed-by: Louis Chauvet Thanks, > if (dt->info.users.len) { > rc = ddebug_module_apply_class_users(dt, &reserved_ids); > if (rc) > diff --git a/lib/test_dynamic_debug.c b/lib/test_dynamic_debug.c > index b1555b0a2bb1..74b98adc4ed0 100644 > --- a/lib/test_dynamic_debug.c > +++ b/lib/test_dynamic_debug.c > @@ -81,7 +81,7 @@ enum cat_disjoint_bits { > D2_DRMRES }; > > /* numeric verbosity, V2 > V1 related */ > -enum cat_level_num { V0 = 14, V1, V2, V3, V4, V5, V6, V7 }; > +enum cat_level_num { V0 = 16, V1, V2, V3, V4, V5, V6, V7 }; > > /* recapitulate DRM's parent(drm.ko) <-- _submod(drivers,helpers) */ > #if !defined(TEST_DYNAMIC_DEBUG_SUBMOD) > @@ -90,6 +90,7 @@ enum cat_level_num { V0 = 14, V1, V2, V3, V4, V5, V6, V7 }; > * classmaps on the client enums above, and then declares the PARAMS > * ref'g the classmaps. Each is exported. > */ > + > DYNDBG_CLASSMAP_DEFINE(map_disjoint_bits, DD_CLASS_TYPE_DISJOINT_BITS, > D2_CORE, > "D2_CORE", > @@ -113,6 +114,14 @@ DYNDBG_CLASSMAP_DEFINE(map_level_num, DD_CLASS_TYPE_LEVEL_NUM, > DYNDBG_CLASSMAP_PARAM(disjoint_bits, p); > DYNDBG_CLASSMAP_PARAM(level_num, p); > > +#ifdef FORCE_CLASSID_CONFLICT_MODPROBE > +/* > + * Enable with -Dflag on compile to test overlapping class-id range > + * detection. This should break on modprobe. > + */ > +DYNDBG_CLASSMAP_DEFINE(classid_range_conflict, 0, D2_CORE + 1, "D3_CORE"); > +#endif > + > #else /* TEST_DYNAMIC_DEBUG_SUBMOD */ > > /* -- Louis Chauvet, Bootlin Embedded Linux and Kernel engineering https://bootlin.com