From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 17F151A92F1; Mon, 17 Jun 2024 13:27:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718630822; cv=none; b=LAFji7ucBZw6BQT8Q7v//eLvdxUqWLLIYtn4OrtsF+nFLRFV3vpOREuho6XJqJSclLEcnManMqgQCNg4nC8gwR7RVoDGAyjIylQJ5VqAaE4AhU35PGhtJ8BWnm0tshtag8G/t7z4RJkCa7zD2l+QWRfcvHT/Te9rnzYP5k8q1Ww= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718630822; c=relaxed/simple; bh=GYf0WT4dWalRZp8O4+Sw9ZSrM9J3fIUdjEsVWP5mT/U=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Y4BzucQzXrPI4iWhDP6AK52B8Qb9kSjtrzrgz76Ybi+X8tf0moW9pED+psOGxa+haV8dTR8xinW0TkZBBtZBJHsSWguoDzCWxZUf81/xVcv+v4gxGRHizOkKXdUrhpnQHAQhs5Qd/Ce6fmEDatC0wMbfqtnXijVEOdWCD/k5gfk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=XPYlXD3Q; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="XPYlXD3Q" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 38E24C4AF1C; Mon, 17 Jun 2024 13:27:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718630821; bh=GYf0WT4dWalRZp8O4+Sw9ZSrM9J3fIUdjEsVWP5mT/U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XPYlXD3QWM4F5jXuS2EK52p/ETW6TjtE65CyMYqsk6/nMJbqJ3Xb5gLcyjyW8203x kqntZ6dPtvM8LXgSztJdklgEoQTFbQgfyRDj4j403EJ4w0/vJp9f71ZoFKhLdV7fsL Vp6qlIB59qZuDavDx3i9lBqhtwj6wuGsJdWFMmsMIKLFE6KCfE77kyaOeSpKVmXGjU C2WTSWLHgVanWPQJ5DjWfj+L3Egr62FJqaW5joFw+7VIzXs2pEtdAuDBffw2gHzsbh BWwu5v5Y1LvEAQJ0yplRji/o9lOzwkyioZTkSa66Klu0BvBj5jXkOuHDpMCs5ZM/lS FfgOCsDMA2m7g== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Masahiro Yamada , Randy Dunlap , Sasha Levin , linux-kbuild@vger.kernel.org Subject: [PATCH AUTOSEL 5.15 21/21] kconfig: remove wrong expr_trans_bool() Date: Mon, 17 Jun 2024 09:25:58 -0400 Message-ID: <20240617132617.2589631-21-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240617132617.2589631-1-sashal@kernel.org> References: <20240617132617.2589631-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 5.15.161 Content-Transfer-Encoding: 8bit From: Masahiro Yamada [ Upstream commit 77a92660d8fe8d29503fae768d9f5eb529c88b36 ] expr_trans_bool() performs an incorrect transformation. [Test Code] config MODULES def_bool y modules config A def_bool y select C if B != n config B def_tristate m config C tristate [Result] CONFIG_MODULES=y CONFIG_A=y CONFIG_B=m CONFIG_C=m This output is incorrect because CONFIG_C=y is expected. Documentation/kbuild/kconfig-language.rst clearly explains the function of the '!=' operator: If the values of both symbols are equal, it returns 'n', otherwise 'y'. Therefore, the statement: select C if B != n should be equivalent to: select C if y Or, more simply: select C Hence, the symbol C should be selected by the value of A, which is 'y'. However, expr_trans_bool() wrongly transforms it to: select C if B Therefore, the symbol C is selected by (A && B), which is 'm'. The comment block of expr_trans_bool() correctly explains its intention: * bool FOO!=n => FOO ^^^^ If FOO is bool, FOO!=n can be simplified into FOO. This is correct. However, the actual code performs this transformation when FOO is tristate: if (e->left.sym->type == S_TRISTATE) { ^^^^^^^^^^ While it can be fixed to S_BOOLEAN, there is no point in doing so because expr_tranform() already transforms FOO!=n to FOO when FOO is bool. (see the "case E_UNEQUAL" part) expr_trans_bool() is wrong and unnecessary. Signed-off-by: Masahiro Yamada Acked-by: Randy Dunlap Signed-off-by: Sasha Levin --- scripts/kconfig/expr.c | 29 ----------------------------- scripts/kconfig/expr.h | 1 - scripts/kconfig/menu.c | 2 -- 3 files changed, 32 deletions(-) diff --git a/scripts/kconfig/expr.c b/scripts/kconfig/expr.c index 81ebf8108ca74..81dfdf4470f75 100644 --- a/scripts/kconfig/expr.c +++ b/scripts/kconfig/expr.c @@ -396,35 +396,6 @@ static struct expr *expr_eliminate_yn(struct expr *e) return e; } -/* - * bool FOO!=n => FOO - */ -struct expr *expr_trans_bool(struct expr *e) -{ - if (!e) - return NULL; - switch (e->type) { - case E_AND: - case E_OR: - case E_NOT: - e->left.expr = expr_trans_bool(e->left.expr); - e->right.expr = expr_trans_bool(e->right.expr); - break; - case E_UNEQUAL: - // FOO!=n -> FOO - if (e->left.sym->type == S_TRISTATE) { - if (e->right.sym == &symbol_no) { - e->type = E_SYMBOL; - e->right.sym = NULL; - } - } - break; - default: - ; - } - return e; -} - /* * e1 || e2 -> ? */ diff --git a/scripts/kconfig/expr.h b/scripts/kconfig/expr.h index 9c9caca5bd5f2..c91060e19e477 100644 --- a/scripts/kconfig/expr.h +++ b/scripts/kconfig/expr.h @@ -296,7 +296,6 @@ void expr_free(struct expr *e); void expr_eliminate_eq(struct expr **ep1, struct expr **ep2); int expr_eq(struct expr *e1, struct expr *e2); tristate expr_calc_value(struct expr *e); -struct expr *expr_trans_bool(struct expr *e); struct expr *expr_eliminate_dups(struct expr *e); struct expr *expr_transform(struct expr *e); int expr_contains_symbol(struct expr *dep, struct symbol *sym); diff --git a/scripts/kconfig/menu.c b/scripts/kconfig/menu.c index 606ba8a63c24e..8c53d9478be1f 100644 --- a/scripts/kconfig/menu.c +++ b/scripts/kconfig/menu.c @@ -380,8 +380,6 @@ void menu_finalize(struct menu *parent) dep = expr_transform(dep); dep = expr_alloc_and(expr_copy(basedep), dep); dep = expr_eliminate_dups(dep); - if (menu->sym && menu->sym->type != S_TRISTATE) - dep = expr_trans_bool(dep); prop->visible.expr = dep; /* -- 2.43.0