From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.10]) (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 EF4AFB67F; Thu, 29 May 2025 17:40:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.10 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748540426; cv=none; b=qs6a0to/uAucMnAzL4HHfVLG9wsd+XsmMq3GuavK0zAKkQ+oV5TlzqhYduTBmZKvpToWCmN9pLZKKpjG/WRl5lBfYCEaroNJyCysw5o7TnedzkGaOY20uFPkcrr1WStooUs9pPkdTimOuUaOMoQWL2Id1C/Vbenw6vk3UeeQSVk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748540426; c=relaxed/simple; bh=CTuAedKq0U54g+MH81XEGkmCLAnq8aSybpfDBpJIdQ4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=EN0+4jRZutimTPsv7Av5swjUI0AMGbxh/0Z02I2cfuy4kND+rq6Y9eN7f4ZzvamfKjFSgcOp/+bOLB/CIZ+8/QTTYI45GelCcZPTrs9bPhW3ud7BKT5XEZEwC9vwnYWCRKcjOLCLNNcZA9cIXpovfoYtRZ629ic2ilJu4fW5/mI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=none smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=a3ybn94Y; arc=none smtp.client-ip=192.198.163.10 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="a3ybn94Y" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1748540424; x=1780076424; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=CTuAedKq0U54g+MH81XEGkmCLAnq8aSybpfDBpJIdQ4=; b=a3ybn94YriLPw0naUJlYW/EuPXmhAzMubVHvb57TCP/4i7YJJro2FDW/ kuLFn73hsn9Z4m01FznfObucT6hA95teb6ixGiWYuG57If8TOxM1Q9Go9 6zHwQtxKdjlynOifE3ppL+Hk8ARuKU5aA+pp4OkoJezQWz/Qi3TaFFWEj fKDZ6+jXzTbMsNfeCsCdKDUhU3LMEiEfzlwSEDHeCAUpKxD3+EZwPbp7W JWk+hLxJgeJIc3ZuDwOG8496UbZCp4UbVoWzDiyq4wHJS+qh8hSZNQ9WN R8awft4+mepUmPU1SRwO8hANqDMgHHGBX+J5HgYo1as7ZVz8bjQVzrIiC w==; X-CSE-ConnectionGUID: ipejCPvORiqXHvYEznl2sA== X-CSE-MsgGUID: UNtPL2HzQB2LTrbbKbgXGg== X-IronPort-AV: E=McAfee;i="6700,10204,11448"; a="61963929" X-IronPort-AV: E=Sophos;i="6.16,193,1744095600"; d="scan'208";a="61963929" Received: from orviesa002.jf.intel.com ([10.64.159.142]) by fmvoesa104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 May 2025 10:40:23 -0700 X-CSE-ConnectionGUID: OvceDlaHQH6JgxsUOXFn1A== X-CSE-MsgGUID: 3iC4sBmBRcyPk8AEgUMAGA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.16,193,1744095600"; d="scan'208";a="174628041" Received: from chandhni-mobl1.amr.corp.intel.com (HELO desk) ([10.125.146.31]) by orviesa002-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 May 2025 10:40:23 -0700 Date: Thu, 29 May 2025 10:40:17 -0700 From: Pawan Gupta To: Richard Narron Cc: Guenter Roeck , Greg Kroah-Hartman , Linux stable , Linux kernel , Linus Torvalds , Dave Hansen Subject: Re: [PATCH 5.15 00/59] 5.15.184-rc1 review Message-ID: <20250529174017.lwctaondsbg7tk37@desk> References: <20250520125753.836407405@linuxfoundation.org> <0f597436-5da6-4319-b918-9f57bde5634a@roeck-us.net> <67f03e41-245e-202-f0df-687cc4d9a915@aaazen.com> <20250528005520.dpip4qe45zvsn7vw@desk> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Wed, May 28, 2025 at 09:49:40PM -0700, Richard Narron wrote: > On Tue, 27 May 2025, Pawan Gupta wrote: > > > On Tue, May 27, 2025 at 12:31:47PM -0700, Richard Narron wrote: > > > On Fri, 23 May 2025, Guenter Roeck wrote: > > > > > > > On 5/20/25 06:49, Greg Kroah-Hartman wrote: > > > > > This is the start of the stable review cycle for the 5.15.184 release. > > > > > There are 59 patches in this series, all will be posted as a response > > > > > to this one. If anyone has any issues with these being applied, please > > > > > let me know. > > > > > > > > > > Responses should be made by Thu, 22 May 2025 12:57:37 +0000. > > > > > Anything received after that time might be too late. > > > > > > > > > > > > > Build reference: v5.15.184 > > > > Compiler version: x86_64-linux-gcc (GCC) 12.4.0 > > > > Assembler version: GNU assembler (GNU Binutils) 2.40 > > > > > > > > Configuration file workarounds: > > > > "s/CONFIG_FRAME_WARN=.*/CONFIG_FRAME_WARN=0/" > > > > > > > > Building i386:defconfig ... passed > > > > Building i386:allyesconfig ... failed > > > > -------------- > > > > Error log: > > > > x86_64-linux-ld: arch/x86/kernel/static_call.o: in function > > > > `__static_call_transform': > > > > static_call.c:(.ref.text+0x46): undefined reference to `cpu_wants_rethunk_at' > > > > make[1]: [Makefile:1234: vmlinux] Error 1 (ignored) > > > > -------------- > > > > Building i386:allmodconfig ... failed > > > > -------------- > > > > Error log: > > > > x86_64-linux-ld: arch/x86/kernel/static_call.o: in function > > > > `__static_call_transform': > > > > static_call.c:(.ref.text+0x46): undefined reference to `cpu_wants_rethunk_at' > > > > make[1]: [Makefile:1234: vmlinux] Error 1 (ignored) > > > > -------------- > > > > > > > > In v5.15.y, cpu_wants_rethunk_at is only built if CONFIG_STACK_VALIDATION=y, > > > > but that is not supported for i386 builds. The dummy function in > > > > arch/x86/include/asm/alternative.h doesn't take that dependency into account. > > > > > > > > > > I found this bug too using the Slackware 15.0 32-bit kernel > > > configuration. > > > > > > Here is a simple work around patch, but there may be a better solution... > > > > > > --- arch/x86/kernel/static_call.c.orig 2025-05-22 05:08:28.000000000 -0700 > > > +++ arch/x86/kernel/static_call.c 2025-05-27 10:25:27.630496538 -0700 > > > @@ -81,9 +81,12 @@ > > > break; > > > > > > case RET: > > > + > > > +#ifdef CONFIG_64BIT > > > if (cpu_wants_rethunk_at(insn)) > > > code = text_gen_insn(JMP32_INSN_OPCODE, insn, x86_return_thunk); > > > else > > > +#endif > > > code = &retinsn; > > > break; > > > > > > > Another option is to define the empty function when CONFIG_STACK_VALIDATION=n as below: > > > > --- 8< --- > > From: Pawan Gupta > > Subject: [PATCH] x86/its: Fix undefined reference to cpu_wants_rethunk_at() > > > > Below error was reported in 32-bit kernel build: > > > > static_call.c:(.ref.text+0x46): undefined reference to `cpu_wants_rethunk_at' > > make[1]: [Makefile:1234: vmlinux] Error > > > > This is because the definition of cpu_wants_rethunk_at() depends on > > CONFIG_STACK_VALIDATION which is only enabled in 64-bit mode. > > > > Define the empty function when CONFIG_STACK_VALIDATION=n, rethunk mitigation > > is anyways not supported without it. > > > > Reported-by: Guenter Roeck > > Link: https://lore.kernel.org/stable/0f597436-5da6-4319-b918-9f57bde5634a@roeck-us.net/ > > Signed-off-by: Pawan Gupta > > --- > > arch/x86/include/asm/alternative.h | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/arch/x86/include/asm/alternative.h b/arch/x86/include/asm/alternative.h > > index 1797f80c10de..a5f704dbb4a1 100644 > > --- a/arch/x86/include/asm/alternative.h > > +++ b/arch/x86/include/asm/alternative.h > > @@ -98,7 +98,7 @@ static inline u8 *its_static_thunk(int reg) > > } > > #endif > > > > -#ifdef CONFIG_RETHUNK > > +#if defined(CONFIG_RETHUNK) && defined(CONFIG_STACK_VALIDATION) > > extern bool cpu_wants_rethunk(void); > > extern bool cpu_wants_rethunk_at(void *addr); > > #else > > -- > > 2.34.1 > > > > Thanks for looking at this Pawan. > > Your new patch works fine on both Slackware 15.0 32-bit and 64-bit > systems. Thank you for verifying the patch.