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 0CFDF1E572F; Fri, 30 May 2025 05:13:53 +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=1748582034; cv=none; b=OLB5WsDmzWl2marI/kDV2iP4qk5RiMN2G9QoHE5tnIDjijHHLQGPa1nPsJubtL+JGuiJZ2+IsvC10/rc+GwBasQNdOn8A+r966d7+9SS3u57DghoIu3oFoam1+1S+I1C17qzJzHU+oaWQllCSs9335OKop36dag8TlFxJDqhkUg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748582034; c=relaxed/simple; bh=0a50+Hp19JQF0AMt+fssCSo2Xt5F5UE65SizAj0FMmw=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=hx7BmlAoGvy5EQ6HDZV4awOLi4anNveWE4Yhp5R63SGgCA5QdCru2aa2pw/8gUlF/VmhO35ijSlsRZhYwsGqKAqTfAgNjZwvA8XLnsG7sL4ngmXldp8EWFBa1Oq7ifZ3AobUkfUFd6YY0AQnGh39yDLsBd57qQ2p730cGjNbd+c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=wlCNc1dB; 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="wlCNc1dB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 18A81C4CEE9; Fri, 30 May 2025 05:13:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1748582033; bh=0a50+Hp19JQF0AMt+fssCSo2Xt5F5UE65SizAj0FMmw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=wlCNc1dB1M2+jmQGGGsvYrTiX7YTWkVBJQ76qyHvwspOJGAtGDhB0sndzDkC/4Gph RuY3wxXDWVmENYgJiAjBKKHRrA/WU2al4Y0yQfPFoSQwfy0O9UcATJBWnOzezPO8Md X+ydF3blCnvBSIQsRU1AJZqhMfvTW/pKEDJdzfDk= Date: Fri, 30 May 2025 07:11:58 +0200 From: Greg Kroah-Hartman To: Pawan Gupta Cc: Richard Narron , Guenter Roeck , Linux stable , Linux kernel , Linus Torvalds , Dave Hansen Subject: Re: [PATCH 5.15 00/59] 5.15.184-rc1 review Message-ID: <2025053037-tribunal-shortlist-5207@gregkh> References: <20250520125753.836407405@linuxfoundation.org> <0f597436-5da6-4319-b918-9f57bde5634a@roeck-us.net> <67f03e41-245e-202-f0df-687cc4d9a915@aaazen.com> <20250528005520.dpip4qe45zvsn7vw@desk> <20250529174017.lwctaondsbg7tk37@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: <20250529174017.lwctaondsbg7tk37@desk> On Thu, May 29, 2025 at 10:40:17AM -0700, Pawan Gupta wrote: > 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. Is someone going to submit this in a form we can apply it in? (hint...)