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 BB7E71BE868; Tue, 18 Jun 2024 12:43:33 +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=1718714613; cv=none; b=PsOu6aHsMYMFvGC2cqgK+LRLS1SdXVJEut1XdAL3Gsbv+R74UQuJ+gpPNBKVksXEr1SuwA/a90kdzpATNlFVPqZ5jODlfFrtGorbUDpYWF7N4Ad/ko3Q0kDpVkHl26R/bLZH7X4UNC0f3qIx4wIXCWvhN4GP5O8oK9Ex1dd1yww= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718714613; c=relaxed/simple; bh=stN5Ld1JXEx7p6jKEsYnl/+iDFWxr690DHHoqxLYQJ0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=U4c6mD9ityCZFTblqpQbzaMk92AtoDAG1m95rTGXMgIJGDqr+LMoGEgVXUq3QbLYabMSrTciPi/nM9m+wyn+h8nBNN4apfHKP2GESoClvRMLaLmcX9poNDryboXwIh1qS/uIW7/keBvWhkqxBQWCApxuYlnWBH0i9ZB9DF1W5YU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=NeNzcT5w; 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="NeNzcT5w" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E56E4C4AF48; Tue, 18 Jun 2024 12:43:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718714613; bh=stN5Ld1JXEx7p6jKEsYnl/+iDFWxr690DHHoqxLYQJ0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NeNzcT5wyH9HmfukN1krPS3PPtMIZmaxnV15pBxJJjC9f/x18446JPtTqzNO8Cdn6 5/9KGso7z/y4VMn6jdcAv03fWZ/7XYdh09ldt1Tpi6/jVNkIvMWxGmvwDHphaP1H0y Ajy2/BneLu6EhAIhW7SSqi2s5vUH7bl1aNbQauqf5e1mv15aKNLEsVeiM7IfiDjLhj NFLLD4kZsJhSWnfmjbyWHnGjE7FaxG4z29PKbjQJVndg9XkEi+tLRUcUpwEJ2EJoGb H1UY7qf4X8j0MFHcZc70YrYP7msdsfDZyG0U634uP5ADtFPE6hZyLD3ykMXYWmAcAe 6bTMJkVD7bRiw== 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 4.19 9/9] kconfig: remove wrong expr_trans_bool() Date: Tue, 18 Jun 2024 08:43:15 -0400 Message-ID: <20240618124318.3304798-9-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240618124318.3304798-1-sashal@kernel.org> References: <20240618124318.3304798-1-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 4.19.316 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 7e38070ee523b..1c69de8cacf6d 100644 --- a/scripts/kconfig/expr.c +++ b/scripts/kconfig/expr.c @@ -395,35 +395,6 @@ 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 43a87f8ea738c..968219750244a 100644 --- a/scripts/kconfig/expr.h +++ b/scripts/kconfig/expr.h @@ -302,7 +302,6 @@ struct expr *expr_copy(const struct expr *org); void expr_free(struct expr *e); void expr_eliminate_eq(struct expr **ep1, struct expr **ep2); 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 4cf15d449c05d..4d48ff3083bd8 100644 --- a/scripts/kconfig/menu.c +++ b/scripts/kconfig/menu.c @@ -390,8 +390,6 @@ 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