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 3D8A919CD17; Thu, 25 Jul 2024 14:43:02 +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=1721918582; cv=none; b=JE6aJ5m7N0CY8YTItI5EvLa+Rd2GMMTBQxEpz7HrLYzRVQjJ2u5sGLhxHnoxpv8LLxonLOovB/8b4k3tRVDh33UIJVQEFDyCWEDDI1+ObVJimOxJKnkdqKoQonKQ/d9qp0hx/N95NwKlwkk9er7SZq58NyPRETvCZMLNxkhIOV4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721918582; c=relaxed/simple; bh=6SNHZoWPKJa7Th7P5FYvg9HKe87MSnlCUPSYR8sL4q0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=qhIZDKypuQSZi8fWPuAf4HSF72UwpoRtTJmiA2x3VxQMCrOdprRhr/EPSRfD/4ZMq8CAq5w7g58m7FOimV7YIa/4908Omw7RpVm6ju4VDfX0u5FsXW3Jp0a4o8B381q36a0lyfBhRLSfIcpAOd7xmG0JLIFKt7e6AlZSHDcu9t4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=N4DIRo++; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="N4DIRo++" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B6C45C32782; Thu, 25 Jul 2024 14:43:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1721918582; bh=6SNHZoWPKJa7Th7P5FYvg9HKe87MSnlCUPSYR8sL4q0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=N4DIRo++ltVrFyccGHFNn9OCJ9XOh204ywDnLww0u+4G4cjOp8P43gpx3A5Xncfsa FyqVH+gZPpJ65NEZUunsH/P4/BwjQhshXGDWLIsGlqjkIGO7+6UbOrptoE5xNZ2Fov X2mJYMV9ksLiEl0Cjg2Mpa6cHB9/So0k8GJi4gjg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Masahiro Yamada , Randy Dunlap , Sasha Levin Subject: [PATCH 5.4 11/43] kconfig: remove wrong expr_trans_bool() Date: Thu, 25 Jul 2024 16:36:34 +0200 Message-ID: <20240725142730.900847124@linuxfoundation.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240725142730.471190017@linuxfoundation.org> References: <20240725142730.471190017@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.4-stable review patch. If anyone has any objections, please let me know. ------------------ 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 9f1de58e9f0c9..9e409418534b8 100644 --- a/scripts/kconfig/expr.c +++ b/scripts/kconfig/expr.c @@ -397,35 +397,6 @@ 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 017843c9a4f42..fbbd8ebe852a1 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 d9d16469859ab..2c95e8a7ef165 100644 --- a/scripts/kconfig/menu.c +++ b/scripts/kconfig/menu.c @@ -387,8 +387,6 @@ 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