From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id DBE0FC25B47 for ; Wed, 25 Oct 2023 09:58:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=q6pvi+QJLw7+df70tQauX9qb8B6sQsXAO2hUAq4km9w=; b=R7nGzfvgWq4lKM tv6qctWZLCCif1RMBFBQPn3jfIDCmFYgMXN2uX8QVtFUVFXqoFmN+ZCiVcJARPICAuMRToUs464Sj xeCudThGsVHuv2ImXbMAN391XdE+axNJfjb1tsvc2kCWqdpJ3BWz3Xw7Y5LyoocxWpyDtK64NG76p Xr99KzHk7zjuoUtY8nzyZhSJRrVGiPOx6vUEtwt/Qy3Sg6awHqGkc43TooRDGXqCPBo+RNoKQxQwz /6kvkM0+ltZ6JK+Ixl62tYMEoMlvMzxWMA1Y70SAmT+ciaFKhFsO4iCWh3aCb6wkKBsLB6GrDTjPZ y0viyvdU0Y1Gd32sg1aA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qvaee-00BtN6-25; Wed, 25 Oct 2023 09:58:24 +0000 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1qvaeb-00BtLo-1c for linux-riscv@lists.infradead.org; Wed, 25 Oct 2023 09:58:22 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1698227899; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=hY1uTHtPvGX6qPxYPyCytvqtD0NKbkwvoAm0a0RsVuk=; b=FFPYVoGq0+DtFPUmCdbMfOVfGYIhTvV8OLQEArHB4jTrJhI34XsblkMdjBuEip9tbSyxhB aPFjRnHsvXgxrFzVtzuH5EqEzajyi3XogGJkqO5BiWLNGSdypMGc8Su8BPbHnHvRAFJURq zJq3mWUL4hGbo+5mBDYljFsoZM2JxEY= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-347-4ArESoOsO4WzaKRFgFR3qQ-1; Wed, 25 Oct 2023 05:58:14 -0400 X-MC-Unique: 4ArESoOsO4WzaKRFgFR3qQ-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 0F3B73C0E237; Wed, 25 Oct 2023 09:58:14 +0000 (UTC) Received: from localhost (unknown [10.72.112.53]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 0ADFA40C6F79; Wed, 25 Oct 2023 09:58:12 +0000 (UTC) Date: Wed, 25 Oct 2023 17:58:10 +0800 From: Baoquan He To: Arnd Bergmann , eric_devolder@yahoo.com Cc: Vivek Goyal , Andrew Morton , linux-kernel@vger.kernel.org, kexec@lists.infradead.org, x86@kernel.org, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-crypto@vger.kernel.org Subject: Re: [PATCH 1/2] kexec: fix KEXEC_FILE dependencies Message-ID: References: <20231023110308.1202042-1-arnd@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.2 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20231025_025821_620896_E4254F80 X-CRM114-Status: GOOD ( 40.76 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org On 10/24/23 at 03:17pm, Arnd Bergmann wrote: > On Tue, Oct 24, 2023, at 14:44, Baoquan He wrote: > > Just add people and mailing list to CC since I didn't find this mail in > > my box, just drag it via 'b4 am'. > > > > On 10/23/23 at 01:01pm, Arnd Bergmann wrote: > > ...... > > >> diff --git a/kernel/Kconfig.kexec b/kernel/Kconfig.kexec > >> index 7aff28ded2f48..bfc636d64ff2b 100644 > >> --- a/kernel/Kconfig.kexec > >> +++ b/kernel/Kconfig.kexec > >> @@ -36,6 +36,7 @@ config KEXEC > >> config KEXEC_FILE > >> bool "Enable kexec file based system call" > >> depends on ARCH_SUPPORTS_KEXEC_FILE > >> + depends on CRYPTO_SHA256=y || !ARCH_SUPPORTS_KEXEC_PURGATORY > > > > I am not sure if the logic is correct. In theory, kexec_file code > > utilizes purgatory to verify the checksum digested during kernel loading > > when try to jump to the kernel. That means kexec_file depends on > > purgatory, but not contrary? > > The expression I wrote is a bit confusing, but I think this just > keeps the existing behavior: > > - on architectures that select ARCH_SUPPORTS_KEXEC_PURGATORY > (powerpc, riscv, s390 and x86), we also require CRYPTO_SHA256 > to be built-in. > - on architectures that do not have ARCH_SUPPORTS_KEXEC_PURGATORY > (arm64 and parisc), CRYPTO_SHA256 is not used and can be disabled > or =m. > > Since ARCH_SUPPORTS_KEXEC_PURGATORY is a 'bool' symbol, it could > be written as > > depends on (ARCH_SUPPORTS_KEXEC_PURGATORY && CRYPTO_SHA256=y) \ > || !ARCH_SUPPORTS_KEXEC_PURGATORY Yes, this seems to be clearer to me. Thanks. > > if you find that clearer. I see that the second patch > actually gets this wrong, it should actually do > > select CRYPTO if ARCH_SUPPORTS_KEXEC_PURGATORY > select CRYPTO_SHA256 if ARCH_SUPPORTS_KEXEC_PURGATORY Yeah, makes sense to me. Hi Eric, Do you have comment about these? > > > With these changes, we can achieve the goal to avoid building issue, > > whereas the code logic becomes confusing. E.g people could disable > > CONFIG_KEXEC_FILE, but still get purgatory code built in which is > > totally useless. > > > > Not sure if I think too much over this. > > I see your point here, and I would suggest changing the > CONFIG_ARCH_SUPPORTS_KEXEC_PURGATORY symbol to just indicate > the availability of the purgatory code for the arch, rather > than actually controlling the code itself. I already mentioned > this for s390, but riscv would need the same thing on top. > > I think the change below should address your concern. > > Arnd > > diff --git a/arch/riscv/kernel/elf_kexec.c b/arch/riscv/kernel/elf_kexec.c > index e60fbd8660c4..3ac341d296db 100644 > --- a/arch/riscv/kernel/elf_kexec.c > +++ b/arch/riscv/kernel/elf_kexec.c > @@ -266,7 +266,7 @@ static void *elf_kexec_load(struct kimage *image, char *kernel_buf, > cmdline = modified_cmdline; > } > > -#ifdef CONFIG_ARCH_SUPPORTS_KEXEC_PURGATORY > +#ifdef CONFIG_KEXEC_FILE > /* Add purgatory to the image */ > kbuf.top_down = true; > kbuf.mem = KEXEC_BUF_MEM_UNKNOWN; > @@ -280,7 +280,7 @@ static void *elf_kexec_load(struct kimage *image, char *kernel_buf, > sizeof(kernel_start), 0); > if (ret) > pr_err("Error update purgatory ret=%d\n", ret); > -#endif /* CONFIG_ARCH_SUPPORTS_KEXEC_PURGATORY */ > +#endif /* CONFIG_KEXEC_FILE */ If so, we don't need the CONFIG_KEXEC_FILE ifdeffery because the file elf_kexec.c relied on CONFIG_KEXEC_FILE enabling to build in. We can just remove the "#ifdef CONFIG_KEXEC_FILE..#endif" as x86 does. > > /* Add the initrd to the image */ > if (initrd != NULL) { > diff --git a/arch/riscv/Kbuild b/arch/riscv/Kbuild > index d25ad1c19f88..ab181d187c23 100644 > --- a/arch/riscv/Kbuild > +++ b/arch/riscv/Kbuild > @@ -5,7 +5,7 @@ obj-$(CONFIG_BUILTIN_DTB) += boot/dts/ > obj-y += errata/ > obj-$(CONFIG_KVM) += kvm/ > > -obj-$(CONFIG_ARCH_SUPPORTS_KEXEC_PURGATORY) += purgatory/ > +obj-$(CONFIG_KEXEC_FILE) += purgatory/ > > # for cleaning > subdir- += boot > diff --git a/arch/s390/Kbuild b/arch/s390/Kbuild > index a5d3503b353c..361aa01dbd49 100644 > --- a/arch/s390/Kbuild > +++ b/arch/s390/Kbuild > @@ -7,7 +7,7 @@ obj-$(CONFIG_S390_HYPFS) += hypfs/ > obj-$(CONFIG_APPLDATA_BASE) += appldata/ > obj-y += net/ > obj-$(CONFIG_PCI) += pci/ > -obj-$(CONFIG_ARCH_SUPPORTS_KEXEC_PURGATORY) += purgatory/ > +obj-$(CONFIG_KEXEC_FILE) += purgatory/ > > # for cleaning > subdir- += boot tools > _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv