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=-16.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 2C2CEC41537 for ; Tue, 10 Aug 2021 18:55:50 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 956D260F25 for ; Tue, 10 Aug 2021 18:55:49 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 956D260F25 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id A12B88D0001; Tue, 10 Aug 2021 14:55:48 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9C2946B0072; Tue, 10 Aug 2021 14:55:48 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8B1098D0001; Tue, 10 Aug 2021 14:55:48 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0160.hostedemail.com [216.40.44.160]) by kanga.kvack.org (Postfix) with ESMTP id 708C96B0071 for ; Tue, 10 Aug 2021 14:55:48 -0400 (EDT) Received: from smtpin27.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 051DF18339483 for ; Tue, 10 Aug 2021 18:55:48 +0000 (UTC) X-FDA: 78460075176.27.30EA47B Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf11.hostedemail.com (Postfix) with ESMTP id 8F202F000585 for ; Tue, 10 Aug 2021 18:55:47 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id A3CE160EC0; Tue, 10 Aug 2021 18:55:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1628621746; bh=F5kTOFRnzjAJrBKXolCjL+dzW0Enob7L6Qo6a9N/FIw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=mnF0CNC25E4oa/W7CwgBWzcyamvcXR62RJwDP1+hoIvOaCnu6u6aaG77F5mBgJCO6 4/bGSTge8ClhoeunKJAzJ948hRgjQhIptS3R43yp9ARM8MtNPwXNGLvI8CiIj/L11a aS+QzDaj3VIGg6EaJg5/UnzPR69tHjLIu96HzU6VtDhhLT47ayOMpo93dX53xzQyCA 0uiuaEGSP5AXuhVpYg5Gv491i3avovaTEBaFIzzGVCIjksQJmFkaS+f4ZtRb2qSNYM 6NrahHn7t/d0xhmc6bQ/nDGDJevaDydcqBRpnmxTlLIiwMsiULeezD+vRbWUP3bIvk 61vSADYEw+Xnw== Date: Tue, 10 Aug 2021 21:55:32 +0300 From: Mike Rapoport To: Guenter Roeck Cc: Andrew Morton , Peter Zijlstra , Catalin Marinas , Dave Hansen , linux-mips@vger.kernel.org, linux-mm@kvack.org, Will Deacon , "H. Peter Anvin" , linux-riscv@lists.infradead.org, Frank Rowand , kvmarm@lists.cs.columbia.edu, linux-s390@vger.kernel.org, linux-acpi@vger.kernel.org, Marc Zyngier , x86@kernel.org, Russell King , Mike Rapoport , Christian Borntraeger , Ingo Molnar , Len Brown , devicetree@vger.kernel.org, Albert Ou , Vasily Gorbik , Heiko Carstens , Rob Herring , Borislav Petkov , Andy Lutomirski , Paul Walmsley , "Kirill A. Shutemov" , Thomas Gleixner , linux-arm-kernel@lists.infradead.org, Thomas Bogendoerfer , Greg Kroah-Hartman , "Rafael J. Wysocki" , linux-kernel@vger.kernel.org, Palmer Dabbelt Subject: Re: [PATCH v3] memblock: make memblock_find_in_range method private Message-ID: References: <20210803064218.6611-1-rppt@kernel.org> <20210809190641.GA1176508@roeck-us.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210809190641.GA1176508@roeck-us.net> Authentication-Results: imf11.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=mnF0CNC2; spf=pass (imf11.hostedemail.com: domain of rppt@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=rppt@kernel.org; dmarc=pass (policy=none) header.from=kernel.org X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 8F202F000585 X-Stat-Signature: 5risbrnzubwef49attc4mbpqugi5fhc1 X-HE-Tag: 1628621747-242068 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, Aug 09, 2021 at 12:06:41PM -0700, Guenter Roeck wrote: > On Tue, Aug 03, 2021 at 09:42:18AM +0300, Mike Rapoport wrote: > > From: Mike Rapoport > > > > There are a lot of uses of memblock_find_in_range() along with > > memblock_reserve() from the times memblock allocation APIs did not exist. > > > > memblock_find_in_range() is the very core of memblock allocations, so any > > future changes to its internal behaviour would mandate updates of all the > > users outside memblock. > > > > Replace the calls to memblock_find_in_range() with an equivalent calls to > > memblock_phys_alloc() and memblock_phys_alloc_range() and make > > memblock_find_in_range() private method of memblock. > > > > This simplifies the callers, ensures that (unlikely) errors in > > memblock_reserve() are handled and improves maintainability of > > memblock_find_in_range(). > > > > Signed-off-by: Mike Rapoport > > I see a number of crashes in next-20210806 when booting x86 images from efi. > > [ 0.000000] efi: EFI v2.70 by EDK II > [ 0.000000] efi: SMBIOS=0x1fbcc000 ACPI=0x1fbfa000 ACPI 2.0=0x1fbfa014 MEMATTR=0x1f25f018 > [ 0.000000] SMBIOS 2.8 present. > [ 0.000000] DMI: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 > [ 0.000000] last_pfn = 0x1ff50 max_arch_pfn = 0x400000000 > [ 0.000000] x86/PAT: Configuration [0-7]: WB WC UC- UC WB WP UC- WT > [ 0.000000] Kernel panic - not syncing: alloc_low_pages: can not alloc memory > [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 5.14.0-rc4-next-20210806 #1 > [ 0.000000] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 > [ 0.000000] Call Trace: > [ 0.000000] ? dump_stack_lvl+0x57/0x7d > [ 0.000000] ? panic+0xfc/0x2c6 > [ 0.000000] ? alloc_low_pages+0x117/0x156 > [ 0.000000] ? phys_pmd_init+0x234/0x342 > [ 0.000000] ? phys_pud_init+0x171/0x337 > [ 0.000000] ? __kernel_physical_mapping_init+0xec/0x276 > [ 0.000000] ? init_memory_mapping+0x1ea/0x2aa > [ 0.000000] ? init_range_memory_mapping+0xdf/0x12e > [ 0.000000] ? init_mem_mapping+0x1e9/0x26f > [ 0.000000] ? setup_arch+0x5ff/0xb6d > [ 0.000000] ? start_kernel+0x71/0x6b4 > [ 0.000000] ? secondary_startup_64_no_verify+0xc2/0xcb > > Bisect points to this patch. Reverting it fixes the problem. Key seems to > be the amount of memory configured in qemu; the problem is not seen if > there is 1G or more of memory, but it is seen with all test boots with > 512M or 256M of memory. It is also seen with almost all 32-bit efi boots. > > The problem is not seen when booting without efi. It looks like this change uncovered a problem in x86::memory_map_top_down(). The allocation in alloc_low_pages() is limited by min_pfn_mapped and max_pfn_mapped. The min_pfn_mapped is updated at every iteration of the loop in memory_map_top_down, but there is another loop in init_range_memory_mapping() that maps several regions below the current min_pfn_mapped without updating this variable. The memory layout in qemu with 256M of RAM and EFI enabled, causes exhaustion of the memory limited by min_pfn_mapped and max_pfn_mapped before min_pfn_mapped is updated. Before this commit there was unconditional "reservation" of 2M in the end of the memory that moved the initial min_pfn_mapped below the memory reserved by EFI. The addition of check for xen_domain() removed this reservation for !XEN and made alloc_low_pages() use the range already busy with EFI data. The patch below moves the update of min_pfn_mapped near the update of max_pfn_mapped so that every time a new range is mapped both limits will be updated accordingly. diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index 1152a29ce109..be279f6e5a0a 100644 --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -1,3 +1,4 @@ +#define DEBUG #include #include #include @@ -485,6 +486,7 @@ static void add_pfn_range_mapped(unsigned long start_pfn, unsigned long end_pfn) nr_pfn_mapped = clean_sort_range(pfn_mapped, E820_MAX_ENTRIES); max_pfn_mapped = max(max_pfn_mapped, end_pfn); + min_pfn_mapped = min(min_pfn_mapped, start_pfn); if (start_pfn < (1UL<<(32-PAGE_SHIFT))) max_low_pfn_mapped = max(max_low_pfn_mapped, @@ -643,7 +645,6 @@ static void __init memory_map_top_down(unsigned long map_start, mapped_ram_size += init_range_memory_mapping(start, last_start); last_start = start; - min_pfn_mapped = last_start >> PAGE_SHIFT; if (mapped_ram_size >= step_size) step_size = get_new_step_size(step_size); } > Guenter > > --- > Bisect log: > > # bad: [da454ebf578f6c542ba9f5b3ddb98db3ede109c1] Add linux-next specific files for 20210809 > # good: [36a21d51725af2ce0700c6ebcb6b9594aac658a6] Linux 5.14-rc5 > git bisect start 'HEAD' 'v5.14-rc5' > # good: [d22fda64bea5f33000e31e5b7e4ba876bca37436] Merge remote-tracking branch 'crypto/master' > git bisect good d22fda64bea5f33000e31e5b7e4ba876bca37436 > # good: [b084da3a98fad27a39ed5ca64106b86df0417851] Merge remote-tracking branch 'irqchip/irq/irqchip-next' > git bisect good b084da3a98fad27a39ed5ca64106b86df0417851 > # good: [a5383d1f57190a33c6afc25c62b9907d84ba2bc6] Merge remote-tracking branch 'staging/staging-next' > git bisect good a5383d1f57190a33c6afc25c62b9907d84ba2bc6 > # good: [a439da3e6abeb054f4e6b0d37814e762b7340196] Merge remote-tracking branch 'seccomp/for-next/seccomp' > git bisect good a439da3e6abeb054f4e6b0d37814e762b7340196 > # bad: [9801f3c0890c7b992b45a5c2afcb16c5cdc8388e] mm/idle_page_tracking: Make PG_idle reusable > git bisect bad 9801f3c0890c7b992b45a5c2afcb16c5cdc8388e > # good: [b4f7f4a9b542836683308d48ffdd18471c6f3e76] lazy-tlb-allow-lazy-tlb-mm-refcounting-to-be-configurable-fix > git bisect good b4f7f4a9b542836683308d48ffdd18471c6f3e76 > # good: [e30842a48c36f094271eea0984bb861b49c49c87] mm/vmscan: add 'else' to remove check_pending label > git bisect good e30842a48c36f094271eea0984bb861b49c49c87 > # bad: [65300b20a21214fb2043419d4e5da1d9947c6e15] mm/madvise: add MADV_WILLNEED to process_madvise() > git bisect bad 65300b20a21214fb2043419d4e5da1d9947c6e15 > # bad: [7348da7a8c244d1a755bc5838b04cb9b1b6ee06c] memblock: make memblock_find_in_range method private > git bisect bad 7348da7a8c244d1a755bc5838b04cb9b1b6ee06c > # good: [98f8c467fe2ba8e553b450b2a3294d69f1f2027f] mm-mempolicy-convert-from-atomic_t-to-refcount_t-on-mempolicy-refcnt-fix > git bisect good 98f8c467fe2ba8e553b450b2a3294d69f1f2027f > # good: [760ded422ebe4f8899905b752d8378c44f2a78f3] mm/memplicy: add page allocation function for MPOL_PREFERRED_MANY policy > git bisect good 760ded422ebe4f8899905b752d8378c44f2a78f3 > # good: [fbfa0492d9639b67119d3d94b7a6a3f85e064260] mm/mempolicy: advertise new MPOL_PREFERRED_MANY > git bisect good fbfa0492d9639b67119d3d94b7a6a3f85e064260 > # good: [ff6d5759a871883aeea38309fb16d91666179328] mm/mempolicy: unify the create() func for bind/interleave/prefer-many policies > git bisect good ff6d5759a871883aeea38309fb16d91666179328 > # first bad commit: [7348da7a8c244d1a755bc5838b04cb9b1b6ee06c] memblock: make memblock_find_in_range method private -- Sincerely yours, Mike.