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 86A99C3DA79 for ; Mon, 15 Jan 2024 08:50:59 +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:From:References:Cc:To: Subject:MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=DiFJgiCQh4TVBYiy8aefoti5Wqxa7gWVqkTj9FBqPKg=; b=cFPXtE1qbH0veB 4pF2o1tkOnjJbglhx2ETv68VwRSmEdlIH/PEDCnoZ9mz8kc7SLeS7NN0KpCDzfTGCCP8+yDR80fAi OkFkTHrgwYSYncB1YJdF48mykBMvT8bYujH11DPxrko5rZG1lG5qT85El7uZppK2c/JnqZLDSMYid IXDviOZB1Cj/aOohiCKePkOG2fxBfr7UKYMr/Jiq6hRorlIG3wnmfIqgagaKRGTNLhbFxg68US/TL tiVwoumxYTOEQ3RH/ZNYHD+j3ETeKvnQTMawxtfj+72dOD0ZMf0sQ5QAUfJoAETdatHHv4K5GIJU7 s9e7cilfTQvSweJZ/sEQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1rPIfw-008JRS-2K; Mon, 15 Jan 2024 08:50:32 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1rPIft-008JNW-09 for linux-arm-kernel@lists.infradead.org; Mon, 15 Jan 2024 08:50:30 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 36B472F4; Mon, 15 Jan 2024 00:51:10 -0800 (PST) Received: from [10.57.76.47] (unknown [10.57.76.47]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 8B77D3F6C4; Mon, 15 Jan 2024 00:50:20 -0800 (PST) Message-ID: <1188e67e-5c04-4bb5-b242-78d92c3fc85c@arm.com> Date: Mon, 15 Jan 2024 08:50:19 +0000 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v9 02/10] mm: Non-pmd-mappable, large folios for folio_add_new_anon_rmap() Content-Language: en-GB To: Jiri Olsa , David Hildenbrand Cc: Andrew Morton , Matthew Wilcox , Yin Fengwei , Yu Zhao , Catalin Marinas , Anshuman Khandual , Yang Shi , "Huang, Ying" , Zi Yan , Luis Chamberlain , Itaru Kitayama , "Kirill A. Shutemov" , John Hubbard , David Rientjes , Vlastimil Babka , Hugh Dickins , Kefeng Wang , Barry Song <21cnbao@gmail.com>, Alistair Popple , linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Barry Song References: <20231207161211.2374093-1-ryan.roberts@arm.com> <20231207161211.2374093-3-ryan.roberts@arm.com> <41dc7dff-1ea8-4894-a487-88d46ec2b2d8@redhat.com> From: Ryan Roberts In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240115_005029_197494_E0A71D75 X-CRM114-Status: GOOD ( 27.23 ) 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 On 14/01/2024 20:55, Jiri Olsa wrote: > On Sun, Jan 14, 2024 at 06:33:56PM +0100, David Hildenbrand wrote: >> On 13.01.24 23:42, Jiri Olsa wrote: >>> On Thu, Dec 07, 2023 at 04:12:03PM +0000, Ryan Roberts wrote: >>>> In preparation for supporting anonymous multi-size THP, improve >>>> folio_add_new_anon_rmap() to allow a non-pmd-mappable, large folio to be >>>> passed to it. In this case, all contained pages are accounted using the >>>> order-0 folio (or base page) scheme. >>>> >>>> Reviewed-by: Yu Zhao >>>> Reviewed-by: Yin Fengwei >>>> Reviewed-by: David Hildenbrand >>>> Reviewed-by: Barry Song >>>> Tested-by: Kefeng Wang >>>> Tested-by: John Hubbard >>>> Signed-off-by: Ryan Roberts >>>> --- >>>> mm/rmap.c | 28 ++++++++++++++++++++-------- >>>> 1 file changed, 20 insertions(+), 8 deletions(-) >>>> >>>> diff --git a/mm/rmap.c b/mm/rmap.c >>>> index 2a1e45e6419f..846fc79f3ca9 100644 >>>> --- a/mm/rmap.c >>>> +++ b/mm/rmap.c >>>> @@ -1335,32 +1335,44 @@ void page_add_anon_rmap(struct page *page, struct vm_area_struct *vma, >>>> * This means the inc-and-test can be bypassed. >>>> * The folio does not have to be locked. >>>> * >>>> - * If the folio is large, it is accounted as a THP. As the folio >>>> + * If the folio is pmd-mappable, it is accounted as a THP. As the folio >>>> * is new, it's assumed to be mapped exclusively by a single process. >>>> */ >>>> void folio_add_new_anon_rmap(struct folio *folio, struct vm_area_struct *vma, >>>> unsigned long address) >>>> { >>>> - int nr; >>>> + int nr = folio_nr_pages(folio); >>>> - VM_BUG_ON_VMA(address < vma->vm_start || address >= vma->vm_end, vma); >>>> + VM_BUG_ON_VMA(address < vma->vm_start || >>>> + address + (nr << PAGE_SHIFT) > vma->vm_end, vma); >>> >>> hi, >>> I'm hitting this bug (console output below) with adding uprobe >>> on simple program like: >>> >>> $ cat up.c >>> int main(void) >>> { >>> return 0; >>> } >>> >>> # bpftrace -e 'uprobe:/home/jolsa/up:_start {}' >>> >>> $ ./up >>> >>> it's on top of current linus tree master: >>> 052d534373b7 Merge tag 'exfat-for-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat >>> >>> before this patch it seems to work, I can send my .config if needed Thanks for the bug report! >> >> bpf only inserts a small folio, so no magic there. >> >> It was: >> VM_BUG_ON_VMA(address < vma->vm_start || address >= vma->vm_end, vma); >> And now it is >> VM_BUG_ON_VMA(address < vma->vm_start || address + (nr << PAGE_SHIFT) > vma->vm_end, vma); >> >> I think this change is sane. As long as the address is aligned to full pages >> (which it better should be) >> >> Staring at uprobe_write_opcode, likely vaddr isn't aligned ... >> >> Likely (hopefully) that is not an issue for __folio_set_anon(), because linear_page_index() >> will mask these bits off. >> >> >> Would the following change fix it for you? And thanks for fixing my mess so quickly, David. FWIW, I agree with your diagnosis. One small suggestion below. > > great, that fixes it for me, you can add my > > Tested-by: Jiri Olsa > > thanks, > jirka > >> >> From c640a8363e47bc96965a35115a040b5f876c4320 Mon Sep 17 00:00:00 2001 >> From: David Hildenbrand >> Date: Sun, 14 Jan 2024 18:32:57 +0100 >> Subject: [PATCH] tmp >> >> Signed-off-by: David Hildenbrand >> --- >> kernel/events/uprobes.c | 2 +- >> mm/rmap.c | 1 + >> 2 files changed, 2 insertions(+), 1 deletion(-) >> >> diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c >> index 485bb0389b488..929e98c629652 100644 >> --- a/kernel/events/uprobes.c >> +++ b/kernel/events/uprobes.c >> @@ -537,7 +537,7 @@ int uprobe_write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm, >> } >> } >> - ret = __replace_page(vma, vaddr, old_page, new_page); >> + ret = __replace_page(vma, vaddr & PAGE_MASK, old_page, new_page); >> if (new_page) >> put_page(new_page); >> put_old: >> diff --git a/mm/rmap.c b/mm/rmap.c >> index f5d43edad529a..a903db4df6b97 100644 >> --- a/mm/rmap.c >> +++ b/mm/rmap.c >> @@ -1408,6 +1408,7 @@ void folio_add_new_anon_rmap(struct folio *folio, struct vm_area_struct *vma, >> { >> int nr = folio_nr_pages(folio); >> + VM_WARN_ON_FOLIO(!IS_ALIGNED(address, PAGE_SIZE), folio); nit: Is it worth also adding this to __folio_add_anon_rmap() so that folio_add_anon_rmap_ptes() and folio_add_anon_rmap_pmd() also benefit? Regardless: Reviewed-by: Ryan Roberts >> VM_WARN_ON_FOLIO(folio_test_hugetlb(folio), folio); >> VM_BUG_ON_VMA(address < vma->vm_start || >> address + (nr << PAGE_SHIFT) > vma->vm_end, vma); >> -- >> 2.43.0 >> >> >> >> -- >> Cheers, >> >> David / dhildenb >> _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel