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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 38358C433F5 for ; Tue, 30 Nov 2021 02:12:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237361AbhK3CPm (ORCPT ); Mon, 29 Nov 2021 21:15:42 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:38518 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231144AbhK3CPg (ORCPT ); Mon, 29 Nov 2021 21:15:36 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1638238337; 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=sCeBnHcCdexUghBmGOQRsKTh1Dzh8Ni6xuNJuelYjvg=; b=YNqMvG8DP6z3sVzFM7s1y/3zHsLIxfiZqPzUj9jBYoe2pD30iUfpyCKknRVnJct9YPhxW3 NLKe3MA8YZXowRy9XG5u/Hx7d1xxG4wwHcyTQiyKIh5Uq9aBo0FENh3jG3VFKBh5JkWLz/ ZjAUKHhsrfqVBoeWs1U2C4mEu1nmGis= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-367-EePJFDdvNJafoxJ8ehC3LA-1; Mon, 29 Nov 2021 21:12:14 -0500 X-MC-Unique: EePJFDdvNJafoxJ8ehC3LA-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 2BB891006AA1; Tue, 30 Nov 2021 02:12:11 +0000 (UTC) Received: from localhost (ovpn-13-215.pek2.redhat.com [10.72.13.215]) by smtp.corp.redhat.com (Postfix) with ESMTPS id D4EE019D9F; Tue, 30 Nov 2021 02:12:04 +0000 (UTC) Date: Tue, 30 Nov 2021 10:12:01 +0800 From: Baoquan He To: Zhen Lei Cc: Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org, "H . Peter Anvin" , linux-kernel@vger.kernel.org, Dave Young , Vivek Goyal , Eric Biederman , kexec@lists.infradead.org, Catalin Marinas , Will Deacon , linux-arm-kernel@lists.infradead.org, Rob Herring , Frank Rowand , devicetree@vger.kernel.org, Jonathan Corbet , linux-doc@vger.kernel.org, Randy Dunlap , Feng Zhou , Kefeng Wang , Chen Zhou Subject: Re: [PATCH v16 00/11] support reserving crashkernel above 4G on arm64 kdump Message-ID: <20211130021201.GM21646@MiWiFi-R3L-srv> References: <20211123124646.1995-1-thunder.leizhen@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20211123124646.1995-1-thunder.leizhen@huawei.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Lei, On 11/23/21 at 08:46pm, Zhen Lei wrote: > There are following issues in arm64 kdump: > 1. We use crashkernel=X to reserve crashkernel below 4G, which > will fail when there is no enough low memory. > 2. If reserving crashkernel above 4G, in this case, crash dump > kernel will boot failure because there is no low memory available > for allocation. > > To solve these issues, change the behavior of crashkernel=X. > crashkernel=X tries low allocation in DMA zone and fall back to high > allocation if it fails. Thanks for this round of posting, I will review the patch series this week. Thanks Baoquan > > We can also use "crashkernel=X,high" to select a high region above > DMA zone, which also tries to allocate at least 256M low memory in > DMA zone automatically and "crashkernel=Y,low" can be used to allocate > specified size low memory. > > When reserving crashkernel in high memory, some low memory is reserved > for crash dump kernel devices. So there may be two regions reserved for > crash dump kernel. > In order to distinct from the high region and make no effect to the use > of existing kexec-tools, rename the low region as "Crash kernel (low)", > and pass the low region by reusing DT property > "linux,usable-memory-range". We made the low memory region as the last > range of "linux,usable-memory-range" to keep compatibility with existing > user-space and older kdump kernels. > > Besides, we need to modify kexec-tools: > arm64: support more than one crash kernel regions(see [1]) > > Another update is document about DT property 'linux,usable-memory-range': > schemas: update 'linux,usable-memory-range' node schema(see [2]) > > This patchset contains the following 11 patches: > > 0001-0004 are some x86 cleanups which prepares for making functionsreserve_crashkernel[_low]() generic. > 0005 makes functions reserve_crashkernel[_low]() generic. > 0006-0008 reimplements arm64 crashkernel=X. > 0009-0010 adds memory for devices by DT property linux,usable-memory-range. > 0011 updates the doc. > > Changes since [v15] > - Aggregate the processing of "linux,usable-memory-range" into one function. > Only patch 9-10 have been updated. > > Changes since [v14] > - Recovering the requirement that the CrashKernel memory regions on X86 > only requires 1 MiB alignment. > - Combine patches 5 and 6 in v14 into one. The compilation warning fixed > by patch 6 was introduced by patch 5 in v14. > - As with crashk_res, crashk_low_res is also processed by > crash_exclude_mem_range() in patch 7. > - Due to commit b261dba2fdb2 ("arm64: kdump: Remove custom linux,usable-memory-range handling") > has removed the architecture-specific code, extend the property "linux,usable-memory-range" > in the platform-agnostic FDT core code. See patch 9. > - Discard the x86 description update in the document, because the description > has been updated by commit b1f4c363666c ("Documentation: kdump: update kdump guide"). > - Change "arm64" to "ARM64" in Doc. > > > Changes since [v13] > - Rebased on top of 5.11-rc5. > - Introduce config CONFIG_ARCH_WANT_RESERVE_CRASH_KERNEL. > Since reserve_crashkernel[_low]() implementations are quite similar on > other architectures, so have CONFIG_ARCH_WANT_RESERVE_CRASH_KERNEL in > arch/Kconfig and select this by X86 and ARM64. > - Some minor cleanup. > > Changes since [v12] > - Rebased on top of 5.10-rc1. > - Keep CRASH_ALIGN as 16M suggested by Dave. > - Drop patch "kdump: add threshold for the required memory". > - Add Tested-by from John. > > Changes since [v11] > - Rebased on top of 5.9-rc4. > - Make the function reserve_crashkernel() of x86 generic. > Suggested by Catalin, make the function reserve_crashkernel() of x86 generic > and arm64 use the generic version to reimplement crashkernel=X. > > Changes since [v10] > - Reimplement crashkernel=X suggested by Catalin, Many thanks to Catalin. > > Changes since [v9] > - Patch 1 add Acked-by from Dave. > - Update patch 5 according to Dave's comments. > - Update chosen schema. > > Changes since [v8] > - Reuse DT property "linux,usable-memory-range". > Suggested by Rob, reuse DT property "linux,usable-memory-range" to pass the low > memory region. > - Fix kdump broken with ZONE_DMA reintroduced. > - Update chosen schema. > > Changes since [v7] > - Move x86 CRASH_ALIGN to 2M > Suggested by Dave and do some test, move x86 CRASH_ALIGN to 2M. > - Update Documentation/devicetree/bindings/chosen.txt. > Add corresponding documentation to Documentation/devicetree/bindings/chosen.txt > suggested by Arnd. > - Add Tested-by from Jhon and pk. > > Changes since [v6] > - Fix build errors reported by kbuild test robot. > > Changes since [v5] > - Move reserve_crashkernel_low() into kernel/crash_core.c. > - Delete crashkernel=X,high. > - Modify crashkernel=X,low. > If crashkernel=X,low is specified simultaneously, reserve spcified size low > memory for crash kdump kernel devices firstly and then reserve memory above 4G. > In addition, rename crashk_low_res as "Crash kernel (low)" for arm64, and then > pass to crash dump kernel by DT property "linux,low-memory-range". > - Update Documentation/admin-guide/kdump/kdump.rst. > > Changes since [v4] > - Reimplement memblock_cap_memory_ranges for multiple ranges by Mike. > > Changes since [v3] > - Add memblock_cap_memory_ranges back for multiple ranges. > - Fix some compiling warnings. > > Changes since [v2] > - Split patch "arm64: kdump: support reserving crashkernel above 4G" as > two. Put "move reserve_crashkernel_low() into kexec_core.c" in a separate > patch. > > Changes since [v1]: > - Move common reserve_crashkernel_low() code into kernel/kexec_core.c. > - Remove memblock_cap_memory_ranges() i added in v1 and implement that > in fdt_enforce_memory_region(). > There are at most two crash kernel regions, for two crash kernel regions > case, we cap the memory range [min(regs[*].start), max(regs[*].end)] > and then remove the memory range in the middle. > > [1]: http://lists.infradead.org/pipermail/kexec/2020-June/020737.html > [2]: https://github.com/robherring/dt-schema/pull/19 > [v1]: https://lkml.org/lkml/2019/4/2/1174 > [v2]: https://lkml.org/lkml/2019/4/9/86 > [v3]: https://lkml.org/lkml/2019/4/9/306 > [v4]: https://lkml.org/lkml/2019/4/15/273 > [v5]: https://lkml.org/lkml/2019/5/6/1360 > [v6]: https://lkml.org/lkml/2019/8/30/142 > [v7]: https://lkml.org/lkml/2019/12/23/411 > [v8]: https://lkml.org/lkml/2020/5/21/213 > [v9]: https://lkml.org/lkml/2020/6/28/73 > [v10]: https://lkml.org/lkml/2020/7/2/1443 > [v11]: https://lkml.org/lkml/2020/8/1/150 > [v12]: https://lkml.org/lkml/2020/9/7/1037 > [v13]: https://lkml.org/lkml/2020/10/31/34 > [v14]: https://lkml.org/lkml/2021/1/30/53 > [v15]: https://lkml.org/lkml/2021/10/19/1405 > > Chen Zhou (10): > x86: kdump: replace the hard-coded alignment with macro CRASH_ALIGN > x86: kdump: make the lower bound of crash kernel reservation > consistent > x86: kdump: use macro CRASH_ADDR_LOW_MAX in functions > reserve_crashkernel() > x86: kdump: move xen_pv_domain() check and insert_resource() to > setup_arch() > x86: kdump: move reserve_crashkernel[_low]() into crash_core.c > arm64: kdump: introduce some macros for crash kernel reservation > arm64: kdump: reimplement crashkernel=X > x86, arm64: Add ARCH_WANT_RESERVE_CRASH_KERNEL config > of: fdt: Add memory for devices by DT property > "linux,usable-memory-range" > kdump: update Documentation about crashkernel > > Zhen Lei (1): > of: fdt: Aggregate the processing of "linux,usable-memory-range" > > Documentation/admin-guide/kdump/kdump.rst | 11 +- > .../admin-guide/kernel-parameters.txt | 11 +- > arch/Kconfig | 3 + > arch/arm64/Kconfig | 1 + > arch/arm64/include/asm/kexec.h | 10 ++ > arch/arm64/kernel/machine_kexec_file.c | 12 +- > arch/arm64/kernel/setup.c | 13 +- > arch/arm64/mm/init.c | 59 ++----- > arch/x86/Kconfig | 2 + > arch/x86/include/asm/elf.h | 3 + > arch/x86/include/asm/kexec.h | 31 +++- > arch/x86/kernel/setup.c | 163 ++---------------- > drivers/of/fdt.c | 45 +++-- > include/linux/crash_core.h | 3 + > include/linux/kexec.h | 2 - > kernel/crash_core.c | 156 +++++++++++++++++ > kernel/kexec_core.c | 17 -- > 17 files changed, 304 insertions(+), 238 deletions(-) > > -- > 2.25.1 > 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 47CD3C433EF for ; Tue, 30 Nov 2021 02:13:50 +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=s3NV/c4CQAJa+T1mKilGr2VyPoIfsGpYyJpqlTKlxuQ=; b=ANDyt1xf9ybOLU QP05YtB8zPNG1SzHZ/pIA98c9Hc+Lb2Yb4dZQjmr96VWCtAUZxGmSb5xezlqzDLJL9ozKutWkp8ly aV6s/I4wZNTkUnSPqH11VS3rhnjCTvHSq1RAPYoteK6h//x+9MXpulgUKNTWarbcNRwCUmOL3sN8k Zaho4INcWTo4VMl1+bqyzra5muj9mPVMz2NwQW501zuf9Yf6lTFIqBNh/OfiiWDlEQzzmTUMwZa1Q +swwCXK9Er/BQdNMsK3Jc7gkpLYwemQ1BSbIg97Di/sCqwQLYNbK0n3QU2SVxCERbgi9ZBulIuN49 CArmye8yF2A5ogRsIEFw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mrsdA-003Ixr-7O; Tue, 30 Nov 2021 02:12:28 +0000 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mrsd4-003Iw5-Mz for linux-arm-kernel@lists.infradead.org; Tue, 30 Nov 2021 02:12:25 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1638238339; 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=sCeBnHcCdexUghBmGOQRsKTh1Dzh8Ni6xuNJuelYjvg=; b=JUKR9qCYJ4JkljiNmAwfkoJslbkBfmm0Vp+dnh3Pe9jLwoyDOIM2luL7NSnrCIUYb9Fduq glLJClmi3u+S9HJ86pfNjFrC4grLfdIU0u5zSyowyiALAxgOSRRvxdG0NiKK1344zLKqBf OYFjpUVcYX+Ccb+LUlDX7Bch6+gHBx0= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-367-EePJFDdvNJafoxJ8ehC3LA-1; Mon, 29 Nov 2021 21:12:14 -0500 X-MC-Unique: EePJFDdvNJafoxJ8ehC3LA-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 2BB891006AA1; Tue, 30 Nov 2021 02:12:11 +0000 (UTC) Received: from localhost (ovpn-13-215.pek2.redhat.com [10.72.13.215]) by smtp.corp.redhat.com (Postfix) with ESMTPS id D4EE019D9F; Tue, 30 Nov 2021 02:12:04 +0000 (UTC) Date: Tue, 30 Nov 2021 10:12:01 +0800 From: Baoquan He To: Zhen Lei Cc: Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org, "H . Peter Anvin" , linux-kernel@vger.kernel.org, Dave Young , Vivek Goyal , Eric Biederman , kexec@lists.infradead.org, Catalin Marinas , Will Deacon , linux-arm-kernel@lists.infradead.org, Rob Herring , Frank Rowand , devicetree@vger.kernel.org, Jonathan Corbet , linux-doc@vger.kernel.org, Randy Dunlap , Feng Zhou , Kefeng Wang , Chen Zhou Subject: Re: [PATCH v16 00/11] support reserving crashkernel above 4G on arm64 kdump Message-ID: <20211130021201.GM21646@MiWiFi-R3L-srv> References: <20211123124646.1995-1-thunder.leizhen@huawei.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20211123124646.1995-1-thunder.leizhen@huawei.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211129_181222_944103_EFDF4422 X-CRM114-Status: GOOD ( 43.38 ) X-BeenThere: linux-arm-kernel@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-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Lei, On 11/23/21 at 08:46pm, Zhen Lei wrote: > There are following issues in arm64 kdump: > 1. We use crashkernel=X to reserve crashkernel below 4G, which > will fail when there is no enough low memory. > 2. If reserving crashkernel above 4G, in this case, crash dump > kernel will boot failure because there is no low memory available > for allocation. > > To solve these issues, change the behavior of crashkernel=X. > crashkernel=X tries low allocation in DMA zone and fall back to high > allocation if it fails. Thanks for this round of posting, I will review the patch series this week. Thanks Baoquan > > We can also use "crashkernel=X,high" to select a high region above > DMA zone, which also tries to allocate at least 256M low memory in > DMA zone automatically and "crashkernel=Y,low" can be used to allocate > specified size low memory. > > When reserving crashkernel in high memory, some low memory is reserved > for crash dump kernel devices. So there may be two regions reserved for > crash dump kernel. > In order to distinct from the high region and make no effect to the use > of existing kexec-tools, rename the low region as "Crash kernel (low)", > and pass the low region by reusing DT property > "linux,usable-memory-range". We made the low memory region as the last > range of "linux,usable-memory-range" to keep compatibility with existing > user-space and older kdump kernels. > > Besides, we need to modify kexec-tools: > arm64: support more than one crash kernel regions(see [1]) > > Another update is document about DT property 'linux,usable-memory-range': > schemas: update 'linux,usable-memory-range' node schema(see [2]) > > This patchset contains the following 11 patches: > > 0001-0004 are some x86 cleanups which prepares for making functionsreserve_crashkernel[_low]() generic. > 0005 makes functions reserve_crashkernel[_low]() generic. > 0006-0008 reimplements arm64 crashkernel=X. > 0009-0010 adds memory for devices by DT property linux,usable-memory-range. > 0011 updates the doc. > > Changes since [v15] > - Aggregate the processing of "linux,usable-memory-range" into one function. > Only patch 9-10 have been updated. > > Changes since [v14] > - Recovering the requirement that the CrashKernel memory regions on X86 > only requires 1 MiB alignment. > - Combine patches 5 and 6 in v14 into one. The compilation warning fixed > by patch 6 was introduced by patch 5 in v14. > - As with crashk_res, crashk_low_res is also processed by > crash_exclude_mem_range() in patch 7. > - Due to commit b261dba2fdb2 ("arm64: kdump: Remove custom linux,usable-memory-range handling") > has removed the architecture-specific code, extend the property "linux,usable-memory-range" > in the platform-agnostic FDT core code. See patch 9. > - Discard the x86 description update in the document, because the description > has been updated by commit b1f4c363666c ("Documentation: kdump: update kdump guide"). > - Change "arm64" to "ARM64" in Doc. > > > Changes since [v13] > - Rebased on top of 5.11-rc5. > - Introduce config CONFIG_ARCH_WANT_RESERVE_CRASH_KERNEL. > Since reserve_crashkernel[_low]() implementations are quite similar on > other architectures, so have CONFIG_ARCH_WANT_RESERVE_CRASH_KERNEL in > arch/Kconfig and select this by X86 and ARM64. > - Some minor cleanup. > > Changes since [v12] > - Rebased on top of 5.10-rc1. > - Keep CRASH_ALIGN as 16M suggested by Dave. > - Drop patch "kdump: add threshold for the required memory". > - Add Tested-by from John. > > Changes since [v11] > - Rebased on top of 5.9-rc4. > - Make the function reserve_crashkernel() of x86 generic. > Suggested by Catalin, make the function reserve_crashkernel() of x86 generic > and arm64 use the generic version to reimplement crashkernel=X. > > Changes since [v10] > - Reimplement crashkernel=X suggested by Catalin, Many thanks to Catalin. > > Changes since [v9] > - Patch 1 add Acked-by from Dave. > - Update patch 5 according to Dave's comments. > - Update chosen schema. > > Changes since [v8] > - Reuse DT property "linux,usable-memory-range". > Suggested by Rob, reuse DT property "linux,usable-memory-range" to pass the low > memory region. > - Fix kdump broken with ZONE_DMA reintroduced. > - Update chosen schema. > > Changes since [v7] > - Move x86 CRASH_ALIGN to 2M > Suggested by Dave and do some test, move x86 CRASH_ALIGN to 2M. > - Update Documentation/devicetree/bindings/chosen.txt. > Add corresponding documentation to Documentation/devicetree/bindings/chosen.txt > suggested by Arnd. > - Add Tested-by from Jhon and pk. > > Changes since [v6] > - Fix build errors reported by kbuild test robot. > > Changes since [v5] > - Move reserve_crashkernel_low() into kernel/crash_core.c. > - Delete crashkernel=X,high. > - Modify crashkernel=X,low. > If crashkernel=X,low is specified simultaneously, reserve spcified size low > memory for crash kdump kernel devices firstly and then reserve memory above 4G. > In addition, rename crashk_low_res as "Crash kernel (low)" for arm64, and then > pass to crash dump kernel by DT property "linux,low-memory-range". > - Update Documentation/admin-guide/kdump/kdump.rst. > > Changes since [v4] > - Reimplement memblock_cap_memory_ranges for multiple ranges by Mike. > > Changes since [v3] > - Add memblock_cap_memory_ranges back for multiple ranges. > - Fix some compiling warnings. > > Changes since [v2] > - Split patch "arm64: kdump: support reserving crashkernel above 4G" as > two. Put "move reserve_crashkernel_low() into kexec_core.c" in a separate > patch. > > Changes since [v1]: > - Move common reserve_crashkernel_low() code into kernel/kexec_core.c. > - Remove memblock_cap_memory_ranges() i added in v1 and implement that > in fdt_enforce_memory_region(). > There are at most two crash kernel regions, for two crash kernel regions > case, we cap the memory range [min(regs[*].start), max(regs[*].end)] > and then remove the memory range in the middle. > > [1]: http://lists.infradead.org/pipermail/kexec/2020-June/020737.html > [2]: https://github.com/robherring/dt-schema/pull/19 > [v1]: https://lkml.org/lkml/2019/4/2/1174 > [v2]: https://lkml.org/lkml/2019/4/9/86 > [v3]: https://lkml.org/lkml/2019/4/9/306 > [v4]: https://lkml.org/lkml/2019/4/15/273 > [v5]: https://lkml.org/lkml/2019/5/6/1360 > [v6]: https://lkml.org/lkml/2019/8/30/142 > [v7]: https://lkml.org/lkml/2019/12/23/411 > [v8]: https://lkml.org/lkml/2020/5/21/213 > [v9]: https://lkml.org/lkml/2020/6/28/73 > [v10]: https://lkml.org/lkml/2020/7/2/1443 > [v11]: https://lkml.org/lkml/2020/8/1/150 > [v12]: https://lkml.org/lkml/2020/9/7/1037 > [v13]: https://lkml.org/lkml/2020/10/31/34 > [v14]: https://lkml.org/lkml/2021/1/30/53 > [v15]: https://lkml.org/lkml/2021/10/19/1405 > > Chen Zhou (10): > x86: kdump: replace the hard-coded alignment with macro CRASH_ALIGN > x86: kdump: make the lower bound of crash kernel reservation > consistent > x86: kdump: use macro CRASH_ADDR_LOW_MAX in functions > reserve_crashkernel() > x86: kdump: move xen_pv_domain() check and insert_resource() to > setup_arch() > x86: kdump: move reserve_crashkernel[_low]() into crash_core.c > arm64: kdump: introduce some macros for crash kernel reservation > arm64: kdump: reimplement crashkernel=X > x86, arm64: Add ARCH_WANT_RESERVE_CRASH_KERNEL config > of: fdt: Add memory for devices by DT property > "linux,usable-memory-range" > kdump: update Documentation about crashkernel > > Zhen Lei (1): > of: fdt: Aggregate the processing of "linux,usable-memory-range" > > Documentation/admin-guide/kdump/kdump.rst | 11 +- > .../admin-guide/kernel-parameters.txt | 11 +- > arch/Kconfig | 3 + > arch/arm64/Kconfig | 1 + > arch/arm64/include/asm/kexec.h | 10 ++ > arch/arm64/kernel/machine_kexec_file.c | 12 +- > arch/arm64/kernel/setup.c | 13 +- > arch/arm64/mm/init.c | 59 ++----- > arch/x86/Kconfig | 2 + > arch/x86/include/asm/elf.h | 3 + > arch/x86/include/asm/kexec.h | 31 +++- > arch/x86/kernel/setup.c | 163 ++---------------- > drivers/of/fdt.c | 45 +++-- > include/linux/crash_core.h | 3 + > include/linux/kexec.h | 2 - > kernel/crash_core.c | 156 +++++++++++++++++ > kernel/kexec_core.c | 17 -- > 17 files changed, 304 insertions(+), 238 deletions(-) > > -- > 2.25.1 > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mrsd4-003Ivy-KJ for kexec@lists.infradead.org; Tue, 30 Nov 2021 02:12:25 +0000 Date: Tue, 30 Nov 2021 10:12:01 +0800 From: Baoquan He Subject: Re: [PATCH v16 00/11] support reserving crashkernel above 4G on arm64 kdump Message-ID: <20211130021201.GM21646@MiWiFi-R3L-srv> References: <20211123124646.1995-1-thunder.leizhen@huawei.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20211123124646.1995-1-thunder.leizhen@huawei.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: Zhen Lei Cc: Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org, "H . Peter Anvin" , linux-kernel@vger.kernel.org, Dave Young , Vivek Goyal , Eric Biederman , kexec@lists.infradead.org, Catalin Marinas , Will Deacon , linux-arm-kernel@lists.infradead.org, Rob Herring , Frank Rowand , devicetree@vger.kernel.org, Jonathan Corbet , linux-doc@vger.kernel.org, Randy Dunlap , Feng Zhou , Kefeng Wang , Chen Zhou Hi Lei, On 11/23/21 at 08:46pm, Zhen Lei wrote: > There are following issues in arm64 kdump: > 1. We use crashkernel=X to reserve crashkernel below 4G, which > will fail when there is no enough low memory. > 2. If reserving crashkernel above 4G, in this case, crash dump > kernel will boot failure because there is no low memory available > for allocation. > > To solve these issues, change the behavior of crashkernel=X. > crashkernel=X tries low allocation in DMA zone and fall back to high > allocation if it fails. Thanks for this round of posting, I will review the patch series this week. Thanks Baoquan > > We can also use "crashkernel=X,high" to select a high region above > DMA zone, which also tries to allocate at least 256M low memory in > DMA zone automatically and "crashkernel=Y,low" can be used to allocate > specified size low memory. > > When reserving crashkernel in high memory, some low memory is reserved > for crash dump kernel devices. So there may be two regions reserved for > crash dump kernel. > In order to distinct from the high region and make no effect to the use > of existing kexec-tools, rename the low region as "Crash kernel (low)", > and pass the low region by reusing DT property > "linux,usable-memory-range". We made the low memory region as the last > range of "linux,usable-memory-range" to keep compatibility with existing > user-space and older kdump kernels. > > Besides, we need to modify kexec-tools: > arm64: support more than one crash kernel regions(see [1]) > > Another update is document about DT property 'linux,usable-memory-range': > schemas: update 'linux,usable-memory-range' node schema(see [2]) > > This patchset contains the following 11 patches: > > 0001-0004 are some x86 cleanups which prepares for making functionsreserve_crashkernel[_low]() generic. > 0005 makes functions reserve_crashkernel[_low]() generic. > 0006-0008 reimplements arm64 crashkernel=X. > 0009-0010 adds memory for devices by DT property linux,usable-memory-range. > 0011 updates the doc. > > Changes since [v15] > - Aggregate the processing of "linux,usable-memory-range" into one function. > Only patch 9-10 have been updated. > > Changes since [v14] > - Recovering the requirement that the CrashKernel memory regions on X86 > only requires 1 MiB alignment. > - Combine patches 5 and 6 in v14 into one. The compilation warning fixed > by patch 6 was introduced by patch 5 in v14. > - As with crashk_res, crashk_low_res is also processed by > crash_exclude_mem_range() in patch 7. > - Due to commit b261dba2fdb2 ("arm64: kdump: Remove custom linux,usable-memory-range handling") > has removed the architecture-specific code, extend the property "linux,usable-memory-range" > in the platform-agnostic FDT core code. See patch 9. > - Discard the x86 description update in the document, because the description > has been updated by commit b1f4c363666c ("Documentation: kdump: update kdump guide"). > - Change "arm64" to "ARM64" in Doc. > > > Changes since [v13] > - Rebased on top of 5.11-rc5. > - Introduce config CONFIG_ARCH_WANT_RESERVE_CRASH_KERNEL. > Since reserve_crashkernel[_low]() implementations are quite similar on > other architectures, so have CONFIG_ARCH_WANT_RESERVE_CRASH_KERNEL in > arch/Kconfig and select this by X86 and ARM64. > - Some minor cleanup. > > Changes since [v12] > - Rebased on top of 5.10-rc1. > - Keep CRASH_ALIGN as 16M suggested by Dave. > - Drop patch "kdump: add threshold for the required memory". > - Add Tested-by from John. > > Changes since [v11] > - Rebased on top of 5.9-rc4. > - Make the function reserve_crashkernel() of x86 generic. > Suggested by Catalin, make the function reserve_crashkernel() of x86 generic > and arm64 use the generic version to reimplement crashkernel=X. > > Changes since [v10] > - Reimplement crashkernel=X suggested by Catalin, Many thanks to Catalin. > > Changes since [v9] > - Patch 1 add Acked-by from Dave. > - Update patch 5 according to Dave's comments. > - Update chosen schema. > > Changes since [v8] > - Reuse DT property "linux,usable-memory-range". > Suggested by Rob, reuse DT property "linux,usable-memory-range" to pass the low > memory region. > - Fix kdump broken with ZONE_DMA reintroduced. > - Update chosen schema. > > Changes since [v7] > - Move x86 CRASH_ALIGN to 2M > Suggested by Dave and do some test, move x86 CRASH_ALIGN to 2M. > - Update Documentation/devicetree/bindings/chosen.txt. > Add corresponding documentation to Documentation/devicetree/bindings/chosen.txt > suggested by Arnd. > - Add Tested-by from Jhon and pk. > > Changes since [v6] > - Fix build errors reported by kbuild test robot. > > Changes since [v5] > - Move reserve_crashkernel_low() into kernel/crash_core.c. > - Delete crashkernel=X,high. > - Modify crashkernel=X,low. > If crashkernel=X,low is specified simultaneously, reserve spcified size low > memory for crash kdump kernel devices firstly and then reserve memory above 4G. > In addition, rename crashk_low_res as "Crash kernel (low)" for arm64, and then > pass to crash dump kernel by DT property "linux,low-memory-range". > - Update Documentation/admin-guide/kdump/kdump.rst. > > Changes since [v4] > - Reimplement memblock_cap_memory_ranges for multiple ranges by Mike. > > Changes since [v3] > - Add memblock_cap_memory_ranges back for multiple ranges. > - Fix some compiling warnings. > > Changes since [v2] > - Split patch "arm64: kdump: support reserving crashkernel above 4G" as > two. Put "move reserve_crashkernel_low() into kexec_core.c" in a separate > patch. > > Changes since [v1]: > - Move common reserve_crashkernel_low() code into kernel/kexec_core.c. > - Remove memblock_cap_memory_ranges() i added in v1 and implement that > in fdt_enforce_memory_region(). > There are at most two crash kernel regions, for two crash kernel regions > case, we cap the memory range [min(regs[*].start), max(regs[*].end)] > and then remove the memory range in the middle. > > [1]: http://lists.infradead.org/pipermail/kexec/2020-June/020737.html > [2]: https://github.com/robherring/dt-schema/pull/19 > [v1]: https://lkml.org/lkml/2019/4/2/1174 > [v2]: https://lkml.org/lkml/2019/4/9/86 > [v3]: https://lkml.org/lkml/2019/4/9/306 > [v4]: https://lkml.org/lkml/2019/4/15/273 > [v5]: https://lkml.org/lkml/2019/5/6/1360 > [v6]: https://lkml.org/lkml/2019/8/30/142 > [v7]: https://lkml.org/lkml/2019/12/23/411 > [v8]: https://lkml.org/lkml/2020/5/21/213 > [v9]: https://lkml.org/lkml/2020/6/28/73 > [v10]: https://lkml.org/lkml/2020/7/2/1443 > [v11]: https://lkml.org/lkml/2020/8/1/150 > [v12]: https://lkml.org/lkml/2020/9/7/1037 > [v13]: https://lkml.org/lkml/2020/10/31/34 > [v14]: https://lkml.org/lkml/2021/1/30/53 > [v15]: https://lkml.org/lkml/2021/10/19/1405 > > Chen Zhou (10): > x86: kdump: replace the hard-coded alignment with macro CRASH_ALIGN > x86: kdump: make the lower bound of crash kernel reservation > consistent > x86: kdump: use macro CRASH_ADDR_LOW_MAX in functions > reserve_crashkernel() > x86: kdump: move xen_pv_domain() check and insert_resource() to > setup_arch() > x86: kdump: move reserve_crashkernel[_low]() into crash_core.c > arm64: kdump: introduce some macros for crash kernel reservation > arm64: kdump: reimplement crashkernel=X > x86, arm64: Add ARCH_WANT_RESERVE_CRASH_KERNEL config > of: fdt: Add memory for devices by DT property > "linux,usable-memory-range" > kdump: update Documentation about crashkernel > > Zhen Lei (1): > of: fdt: Aggregate the processing of "linux,usable-memory-range" > > Documentation/admin-guide/kdump/kdump.rst | 11 +- > .../admin-guide/kernel-parameters.txt | 11 +- > arch/Kconfig | 3 + > arch/arm64/Kconfig | 1 + > arch/arm64/include/asm/kexec.h | 10 ++ > arch/arm64/kernel/machine_kexec_file.c | 12 +- > arch/arm64/kernel/setup.c | 13 +- > arch/arm64/mm/init.c | 59 ++----- > arch/x86/Kconfig | 2 + > arch/x86/include/asm/elf.h | 3 + > arch/x86/include/asm/kexec.h | 31 +++- > arch/x86/kernel/setup.c | 163 ++---------------- > drivers/of/fdt.c | 45 +++-- > include/linux/crash_core.h | 3 + > include/linux/kexec.h | 2 - > kernel/crash_core.c | 156 +++++++++++++++++ > kernel/kexec_core.c | 17 -- > 17 files changed, 304 insertions(+), 238 deletions(-) > > -- > 2.25.1 > _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec