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 X-Spam-Level: X-Spam-Status: No, score=-10.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3212EC5517A for ; Wed, 11 Nov 2020 13:30:54 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 6182B206CA for ; Wed, 11 Nov 2020 13:30:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="OjHK99pu" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6182B206CA Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date:Message-ID:From: References:To:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=GpkknVF83Kvwg/uqNCpRAr3xazIFT2Hlix/B+/jBU/w=; b=OjHK99pui9lyQLiBR6qFR5Sfz 43PnUCn3wbdq65zTkzHtQnaGUcxnxUZYg7WpKUm9KuQE/CuTwu/GOyJazm3+eQ0v+5Uqr5F3gaLti yUuHFfKShLrhUXL/rHBtR8144L74qdSzqDIFoI64J6vDo+b7PBh+a1p54D5eFlZuewk7oRLgjcxNU DRuEzM0HmBNEI5JBbz+Cr1j0Ac4LU7MPe6Ia6GsPcRdhPHAMKHEEJ4+3jWlqHhBR6lUqm1p+SWDDm lavCwf87hvkmhHD66Vx/IbBLHpiHu0nKGrk3uvQZtTi9BbJd+wXkAvFHgCvJNhl/YQ6thHWF22rO7 gfkE11Frg==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kcqCe-0006Og-TM; Wed, 11 Nov 2020 13:30:24 +0000 Received: from szxga04-in.huawei.com ([45.249.212.190]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kcqCV-0006JV-1B; Wed, 11 Nov 2020 13:30:20 +0000 Received: from DGGEMS404-HUB.china.huawei.com (unknown [172.30.72.59]) by szxga04-in.huawei.com (SkyGuard) with ESMTP id 4CWQZQ5HGwz15VJw; Wed, 11 Nov 2020 21:29:50 +0800 (CST) Received: from [10.174.176.61] (10.174.176.61) by DGGEMS404-HUB.china.huawei.com (10.3.19.204) with Microsoft SMTP Server id 14.3.487.0; Wed, 11 Nov 2020 21:29:53 +0800 Subject: Re: [PATCH v13 0/8] support reserving crashkernel above 4G on arm64 kdump To: Baoquan He , References: <20201031074437.168008-1-chenzhou10@huawei.com> <20201111030136.GD8486@MiWiFi-R3L-srv> From: chenzhou Message-ID: <04a893e6-1412-5fa8-8dbd-8ec278879965@huawei.com> Date: Wed, 11 Nov 2020 21:29:51 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.7.1 MIME-Version: 1.0 In-Reply-To: <20201111030136.GD8486@MiWiFi-R3L-srv> X-Originating-IP: [10.174.176.61] X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201111_083017_544660_376DDACB X-CRM114-Status: GOOD ( 24.54 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: horms@verge.net.au, John.P.donnelly@oracle.com, guohanjun@huawei.com, xiexiuqi@huawei.com, arnd@arndb.de, will@kernel.org, corbet@lwn.net, catalin.marinas@arm.com, linux-doc@vger.kernel.org, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, robh+dt@kernel.org, wangkefeng.wang@huawei.com, mingo@redhat.com, james.morse@arm.com, linux-arm-kernel@lists.infradead.org, huawei.libin@huawei.com, prabhakar.pkin@gmail.com, tglx@linutronix.de, dyoung@redhat.com, nsaenzjulienne@suse.de 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 Baoquan, Bhupesh, On 2020/11/11 11:01, Baoquan He wrote: > Hi Zhou, Bhupesh > > On 10/31/20 at 03:44pm, Chen Zhou 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. >> 3. Since commit 1a8e1cef7603 ("arm64: use both ZONE_DMA and ZONE_DMA32"), >> if the memory reserved for crash dump kernel falled in ZONE_DMA32, >> the devices in crash dump kernel need to use ZONE_DMA will alloc >> fail. > I went through this patchset, mainly the x86 related and generic > changes, the changes look great and no risk. And I know Bhupesh is > following up this and helping review, thanks, both. > > So you have also tested crashkernel reservation on x86_64, with the > normal reservation, and high/low reservation, it is working well, > right? Asking this because I didn't see the test result description, and > just note it. Yeah, i also tested on x86_64 and work well. I did these basic tests before sending every new version. But Bhupesh may have some review comments(Bhupesh referred one month ago). Thanks, Chen Zhou > > Thanks > Baoquan > >> To solve these issues, change the behavior of crashkernel=X. >> crashkernel=X tries low allocation in DMA zone (or the DMA32 zone if >> CONFIG_ZONE_DMA is disabled), and fall back to high allocation if it fails. >> >> 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 (or the DMA32 zone if CONFIG_ZONE_DMA is disabled). >> "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 eight patches: >> 0001-x86-kdump-replace-the-hard-coded-alignment-with-macr.patch >> 0002-x86-kdump-make-the-lower-bound-of-crash-kernel-reser.patch >> 0003-x86-kdump-use-macro-CRASH_ADDR_LOW_MAX-in-functions-.patch >> 0004-x86-kdump-move-reserve_crashkernel-_low-into-crash_c.patch >> 0005-arm64-kdump-introduce-some-macroes-for-crash-kernel-.patch >> 0006-arm64-kdump-reimplement-crashkernel-X.patch >> 0007-arm64-kdump-add-memory-for-devices-by-DT-property-li.patch >> 0008-kdump-update-Documentation-about-crashkernel.patch >> >> 0001-0003 are some x86 cleanups which prepares for making >> functionsreserve_crashkernel[_low]() generic. >> 0004 makes functions reserve_crashkernel[_low]() generic. >> 0005-0006 reimplements arm64 crashkernel=X. >> 0007 adds memory for devices by DT property linux,usable-memory-range. >> 0008 updates the doc. >> >> 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 >> >> Chen Zhou (8): >> 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 reserve_crashkernel[_low]() into crash_core.c >> arm64: kdump: introduce some macroes for crash kernel reservation >> arm64: kdump: reimplement crashkernel=X >> arm64: kdump: add memory for devices by DT property >> linux,usable-memory-range >> kdump: update Documentation about crashkernel >> >> Documentation/admin-guide/kdump/kdump.rst | 23 ++- >> .../admin-guide/kernel-parameters.txt | 12 +- >> arch/arm64/include/asm/kexec.h | 15 ++ >> arch/arm64/include/asm/processor.h | 1 + >> arch/arm64/kernel/setup.c | 13 +- >> arch/arm64/mm/init.c | 105 ++++------- >> arch/arm64/mm/mmu.c | 4 + >> arch/x86/include/asm/kexec.h | 28 +++ >> arch/x86/kernel/setup.c | 153 +--------------- >> include/linux/crash_core.h | 4 + >> include/linux/kexec.h | 2 - >> kernel/crash_core.c | 168 ++++++++++++++++++ >> kernel/kexec_core.c | 17 -- >> 13 files changed, 301 insertions(+), 244 deletions(-) >> >> -- >> 2.20.1 >> > . > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel