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 305D71BDEC; Wed, 3 Jan 2024 17:09:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="Dks1W3GY" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 891DBC433C7; Wed, 3 Jan 2024 17:09:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1704301766; bh=8ZynEfv4p/4nkrg/hsYGLyBaDRVShKp/LCJERGlyoPw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Dks1W3GYRdSr8rOW/fAAI79FwUluBhXQT8i96ZJMk6MIHhAi6Lf/xokXBlQfQGKLn 5zQC3pQGCGF3OeBUFrYn1gJOLrBaVNBHELfJoRQ2WBFjStCWskQWlx0wDrMnJYESOm CZVYRBkqJrAE7oIPgcM9HfuRvjOIT3sEWjh71HiQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Heiko Carstens , Hendrik Brueckner , Alexander Gordeev , Sasha Levin Subject: [PATCH 5.10 05/75] s390/vx: fix save/restore of fpu kernel context Date: Wed, 3 Jan 2024 17:54:46 +0100 Message-ID: <20240103164843.772456150@linuxfoundation.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240103164842.953224409@linuxfoundation.org> References: <20240103164842.953224409@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 5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Heiko Carstens [ Upstream commit e6b2dab41888332bf83f592131e7ea07756770a4 ] The KERNEL_FPR mask only contains a flag for the first eight vector registers. However floating point registers overlay parts of the first sixteen vector registers. This could lead to vector register corruption if a kernel fpu context uses any of the vector registers 8 to 15 and is interrupted or calls a KERNEL_FPR context. If that context uses also vector registers 8 to 15, their contents will be corrupted on return. Luckily this is currently not a real bug, since the kernel has only one KERNEL_FPR user with s390_adjust_jiffies() and it is only using floating point registers 0 to 2. Fix this by using the correct bits for KERNEL_FPR. Fixes: 7f79695cc1b6 ("s390/fpu: improve kernel_fpu_[begin|end]") Signed-off-by: Heiko Carstens Reviewed-by: Hendrik Brueckner Signed-off-by: Alexander Gordeev Signed-off-by: Sasha Levin --- arch/s390/include/asm/fpu/api.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/s390/include/asm/fpu/api.h b/arch/s390/include/asm/fpu/api.h index 34a7ae68485c6..be16a6c0f1276 100644 --- a/arch/s390/include/asm/fpu/api.h +++ b/arch/s390/include/asm/fpu/api.h @@ -76,7 +76,7 @@ static inline int test_fp_ctl(u32 fpc) #define KERNEL_VXR_HIGH (KERNEL_VXR_V16V23|KERNEL_VXR_V24V31) #define KERNEL_VXR (KERNEL_VXR_LOW|KERNEL_VXR_HIGH) -#define KERNEL_FPR (KERNEL_FPC|KERNEL_VXR_V0V7) +#define KERNEL_FPR (KERNEL_FPC|KERNEL_VXR_LOW) struct kernel_fpu; -- 2.43.0