From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id C1E8D80BFF; Fri, 7 Feb 2025 10:21:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738923708; cv=none; b=e1Hgon0rESAQu4VkLqPTjUI5ooRBs5qYi/kWrUHrr8emK5RmtWfdalxbXm0Ii1qcboFoo7UApQWwVdB3gjOdgqnGIHoZjJnbOSQalbjdJOpbWy/8Fhr17kZbl7KsSv039akUHD0uYv7BOwdqgGhQpifkx02M47j24DXCcyBo+dM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738923708; c=relaxed/simple; bh=Z9G/KBGEl6Byxr08x6OT7vhgRLei0KOl+J1GPs7OByM=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=OukmUJfkYWDiY9ewtvrzfxZnL36y0SyBT3flRKIRweShdvv9SEekLdFg60rpEYUQmpFW9h6HVc06Ff5JYyKzHVHyGGf0sSXR0jhXM/PNGTFDB4BnswTuzJYGgZlyh7NS8yxSmXVjJaZSgQwsWOC0AzIhk4KrMlXNSaDb4z4DKok= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com 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 927F2113E; Fri, 7 Feb 2025 02:22:08 -0800 (PST) Received: from [10.162.16.89] (a077893.blr.arm.com [10.162.16.89]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 407113F63F; Fri, 7 Feb 2025 02:21:39 -0800 (PST) Message-ID: <15660c4c-5c4d-4229-b5c5-abcabd402058@arm.com> Date: Fri, 7 Feb 2025 15:51:37 +0530 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v1 13/16] mm: Don't skip arch_sync_kernel_mappings() in error paths To: Ryan Roberts , Catalin Marinas , Will Deacon , Muchun Song , Pasha Tatashin , Andrew Morton , Uladzislau Rezki , Christoph Hellwig , Mark Rutland , Ard Biesheuvel , Dev Jain , Alexandre Ghiti , Steve Capper , Kevin Brodsky Cc: linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org References: <20250205151003.88959-1-ryan.roberts@arm.com> <20250205151003.88959-14-ryan.roberts@arm.com> Content-Language: en-US From: Anshuman Khandual In-Reply-To: <20250205151003.88959-14-ryan.roberts@arm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 2/5/25 20:39, Ryan Roberts wrote: > Fix callers that previously skipped calling arch_sync_kernel_mappings() > if an error occurred during a pgtable update. The call is still required > to sync any pgtable updates that may have occurred prior to hitting the > error condition. > > These are theoretical bugs discovered during code review. > > Cc: > Fixes: 2ba3e6947aed ("mm/vmalloc: track which page-table levels were modified") > Fixes: 0c95cba49255 ("mm: apply_to_pte_range warn and fail if a large pte is encountered") > Signed-off-by: Ryan Roberts This change could stand on its own and LGTM. Reviewed-by: Anshuman Khandual > --- > mm/memory.c | 6 ++++-- > mm/vmalloc.c | 4 ++-- > 2 files changed, 6 insertions(+), 4 deletions(-) > > diff --git a/mm/memory.c b/mm/memory.c > index 539c0f7c6d54..a15f7dd500ea 100644 > --- a/mm/memory.c > +++ b/mm/memory.c > @@ -3040,8 +3040,10 @@ static int __apply_to_page_range(struct mm_struct *mm, unsigned long addr, > next = pgd_addr_end(addr, end); > if (pgd_none(*pgd) && !create) > continue; > - if (WARN_ON_ONCE(pgd_leaf(*pgd))) > - return -EINVAL; > + if (WARN_ON_ONCE(pgd_leaf(*pgd))) { > + err = -EINVAL; > + break; > + } > if (!pgd_none(*pgd) && WARN_ON_ONCE(pgd_bad(*pgd))) { > if (!create) > continue; > diff --git a/mm/vmalloc.c b/mm/vmalloc.c > index 6111ce900ec4..68950b1824d0 100644 > --- a/mm/vmalloc.c > +++ b/mm/vmalloc.c > @@ -604,13 +604,13 @@ static int vmap_small_pages_range_noflush(unsigned long addr, unsigned long end, > mask |= PGTBL_PGD_MODIFIED; > err = vmap_pages_p4d_range(pgd, addr, next, prot, pages, &nr, &mask); > if (err) > - return err; > + break; > } while (pgd++, addr = next, addr != end); > > if (mask & ARCH_PAGE_TABLE_SYNC_MASK) > arch_sync_kernel_mappings(start, end); > > - return 0; > + return err; > } > > /*