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 D0667F9E8; Tue, 16 Jul 2024 15:41:10 +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=1721144470; cv=none; b=I7zcLNOnCueXelXtDqZ82hXG4BvHFQOxMlsW2nLBx4IasbHBv1VgEFJvTZJ7Nranpkc8dT0prGwkxpFklwrPoCLGc+TgQJsHMkziES8jIhrNVBOt9KfU+TKExhEpeJg+1jScQyu7JtIuS9WFMBsfA24v7YBoAxvcn3X3GCyROug= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721144470; c=relaxed/simple; bh=WGA0dQVzNTnpNyiCi/9Ch3JKbwGIdIDMbC4iKW9GSbA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=T3Y/lhMJ/Wk7W6n4wTlv5sF576El6nQxy5PL+/3BIf3NopBZn3KEQCiKJt4KNGLI6f3/X8lOyyrbZs5E4PGr1Mf/FtU7ogghlbNppPV0+zM/NyHRyIjX2yRtxN3QRYF1b/mb26jgoDhuZsEOdPk6hqFhux+cXXA9RvmdWEMCQDU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=VLqvMqY7; 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="VLqvMqY7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 02B7FC116B1; Tue, 16 Jul 2024 15:41:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1721144470; bh=WGA0dQVzNTnpNyiCi/9Ch3JKbwGIdIDMbC4iKW9GSbA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VLqvMqY7xofHGnXeSzPjbROq9q6VC80VQPic4D6O1rnSRf9JOPMejoRHvMd2ZvEhj FQ7WOrEXRzXNgRdYzJ0nSLU1zHCh3ij2o/hrKvgf6ERF8dtASHLWOo1M/RRO3KoD9Q /V2qfKqgwkkAz26yDaAgr9dkI9PHxoE2w8+6qC0U= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Heiko Carstens , Sven Schnelle , Alexander Gordeev , Sasha Levin Subject: [PATCH 5.4 56/78] s390: Mark psw in __load_psw_mask() as __unitialized Date: Tue, 16 Jul 2024 17:31:28 +0200 Message-ID: <20240716152742.809875902@linuxfoundation.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240716152740.626160410@linuxfoundation.org> References: <20240716152740.626160410@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev 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: Sven Schnelle [ Upstream commit 7278a8fb8d032dfdc03d9b5d17e0bc451cdc1492 ] Without __unitialized, the following code is generated when INIT_STACK_ALL_ZERO is enabled: 86: d7 0f f0 a0 f0 a0 xc 160(16,%r15), 160(%r15) 8c: e3 40 f0 a0 00 24 stg %r4, 160(%r15) 92: c0 10 00 00 00 08 larl %r1, 0xa2 98: e3 10 f0 a8 00 24 stg %r1, 168(%r15) 9e: b2 b2 f0 a0 lpswe 160(%r15) The xc is not adding any security because psw is fully initialized with the following instructions. Add __unitialized to the psw definitiation to avoid the superfluous clearing of psw. Reviewed-by: Heiko Carstens Signed-off-by: Sven Schnelle Signed-off-by: Alexander Gordeev Signed-off-by: Sasha Levin --- arch/s390/include/asm/processor.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h index 48d6ccdef5f77..00bb2d287f740 100644 --- a/arch/s390/include/asm/processor.h +++ b/arch/s390/include/asm/processor.h @@ -256,8 +256,8 @@ static inline void __load_psw(psw_t psw) */ static __always_inline void __load_psw_mask(unsigned long mask) { + psw_t psw __uninitialized; unsigned long addr; - psw_t psw; psw.mask = mask; -- 2.43.0